Staphylococcus

Clin Infect Dis, 2005 Jan 15, 40(2), 280 - 5 Epub 2004 Dec 21.
Inducible clindamycin resistance in Staphylococci: should clinicians and microbiologists be concerned?
Lewis JS 2nd, Jorgensen JH.
The increasing incidence of a variety of infections due to Staphylococcus aureus--and, especially, the expanding role of community-associated methicillin-resistant S . aureus (MRSA)--has led to emphasis on the need for safe and effective agents to treat both systemic and localized staphylococcal infections . Unlike most previously noted strains of health care-associated MRSA, community-acquired MRSA isolates are often susceptible to several non- beta -lactam drug classes, although they are usually not susceptible to macrolides . Several newer antimicrobial agents and a few older agents are available for treatment of systemic staphylococcal infections, but use may be limited by the relatively high cost of these agents or the need for parenteral administration . Inexpensive oral agents for treatment of localized, community-acquired MRSA infection include clindamycin, trimethoprim-sulfamethoxazole, and newer tetracyclines . Clindamycin has been used successfully to treat pneumonia and soft-tissue and musculoskeletal infections due to MRSA in adults and children . However, concern over the possibility of emergence of clindamycin resistance during therapy has discouraged some clinicians from prescribing that agent . Simple laboratory testing (e.g., the erythromycin-clindamycin "D-zone" test) can separate strains that have the genetic potential (i.e., the presence of erm genes) to become resistant during therapy from strains that are fully susceptible to clindamycin.

Curr Opin Otolaryngol Head Neck Surg, 2005 Feb, 13(1), 39 - 44
Superantigen hypothesis for the early development of chronic hyperplastic sinusitis with massive nasal polyposis; Bernstein JM et al.; PURPOSE OF REVIEW: The pathogenesis, pathophysiology, and immunobiology of chronic hyperplastic sinusitis with massive nasal polyposis are starting to become unraveled . Allergy, viral infection, bacterial infection, fungal infection, and environmental pollution have all been suggested as possible initial triggers that may upregulate inflammation of the lateral wall of the nose to develop nasal polyposis . The purpose of this review is to present data from our laboratory that suggest that one of the possible early events in the development of inflammation of the lateral wall of the nose in chronic hyperplastic sinusitis with massive nasal polyposis is the production of exotoxins from Staphylococcus aureus . The exotoxins may act as superantigens and cause activation and clonal expansion of lymphocytes with specific Vbeta regions, resulting in massive cytokine production . RECENT FINDINGS: Recent published studies suggest that S . aureus is the most common organism isolated from the mucus adjacent to massive nasal polyposis . Staphylococci produce exotoxins . These exotoxins, sometimes known as enterotoxins, include SEA, SEB, and TSST-1 . These exotoxins are capable of acting as superantigens and therefore, reacting with T lymphocytes with specific Vbetas in the lateral wall of the nose . Thereafter, it is possible that these lymphocytes are stimulated to produce both TH1 and TH2 cytokines, which have also been demonstrated in the nasal polyp . The consequence of these findings may be the upregulation and increased survival of eosinophils in the nasal polyp . SUMMARY: Staphylococcus aureus is present in the mucin adjacent to nasal polyps in about 60 to 70% of cases of massive nasal polyposis . These organism, as studied up to the present, always produce exotoxins, which may act as superantigens, causing activation and clonal expansion of lymphocytes with specific Vbeta region in the lateral wall of the nose . The present review suggests that activation of these lymphocytes produce both TH1 and TH2 cytokines . The potential damage to the nasal mucosa from eosinophils is briefly discussed . Theoretically, topical antibiotics to suppress the colonization of S . aureus may be a logical approach to downregulate the production of superantigen in the lateral wall of the nose after appropriate endoscopic sinus surgery.

Indian J Med Res, 2004 Dec, 120(6), 546 - 52
In vitro activity of linezolid & quinupristin/dalfopristin against Gram-positive cocci; Tunger A et al.; BACKGROUND & OBJECTIVES: Since the incidence of vancomycin- and methicillin-resistant Grampositive infections continue to increase, novel antimicrobials such as linezolid and streptogramin may provide new options to treat patients . The aim of this study was to investigate in vitro susceptibility of Enterococcus faecium resistant to glycopeptides, coagulase negative staphylococci and S . aureus resistant to methicillin isolated mainly from blood and also rectal swab cultures of patients against quinupristin/dalfopristin and linezolid . METHODS: The in vitro susceptibility to linezolid and quinupristin/dalfopristin for a total of 332 isolates of Gram-positive cocci {127 methicillin-resistant Staphylococcus aureus, 109 methicillinresistant coagulase negative staphylococci (71 S . epidermidis, 38 S . haemolyticus) and 96 vanA genotype vancomycin-resistant Enterococcus faecium} was investigated by E test . RESULTS: All MRSA and MRCoNS isolates were susceptible to linezolid (MICs < 4.0 mg/l) . Ninety per cent of VRE isolates were inhibited by linezolid at concentration of 2.0 mg/l and presented similar activities to quinupristin/dalfopristin . MICs for quinupristin/dalfopristin against staphylococci were also low (MIC(90) = 1.0 mg/l for both MRSA and MRCoNS isolates) . INTERPRETATION & CONCLUSION: The results of the present study demonstrated that quinupristin/ dalfopristin and linezolid, have good in vitro activity against MRSA, MRCoNS and vancomycin resistant E . faecium in Turkey . These drugs could be promising therapeutic options in an era of rapidly growing antibiotic resistance in all parts of world.

J Dairy Sci, 2005 Feb, 88(2), 577 - 9
Short communication: association between milk yield at dry-off and probability of intramammary infections at calving; Rajala-Schultz PJ et al.; The association between milk yield at dry-off and intramammary infections at calving was evaluated from 116 lactations in one herd . Duplicate quarter samples were collected within 3 d after calving to estimate prevalence of intramammary infection at calving; information on cows' parity, daily milk yields, weekly somatic cell counts, and dry-off and calving dates were available for the data analyses . Generalized linear models with logit link were used to model the probability of a cow or a quarter being infected at calving, accounting for the clustered data . Increasing milk production at dry-off was a significant risk factor for both a cow and a quarter being infected with environmental pathogens at calving, but infections caused by coagulase-negative staphylococci at calving were not associated with milk yield at dry-off . For every 5-kg increase in milk yield at dry-off above 12.5 kg, the odds of a cow having an environmental intramammary infection at calving increased at least by 77%.

J Antimicrob Chemother . 2005 Jan 13; {Epub ahead of print}
Evaluation of cefoxitin 5 and 10 {micro}g discs for the detection of methicillin resistance in staphylococci; Skov R et al.; OBJECTIVE: To evaluate cefoxitin 5 and 10 microg discs for detection of methicillin resistance in staphylococci . METHODS: Six hundred and forty-one Staphylococcus aureus (261 mecA-negative and 380 mecA-positive) and 344 coagulase-negative staphylococci (CoNS) (132 mecA-negative and 212 mecA-positive) were investigated . The CoNS represented nine species, Staphylococcus epidermidis being the most frequent (n=231) . All isolates were tested using semi-confluent growth on Iso-Sensitest agar (ISA), and Mueller-Hinton agar (MH) using a 5 and a 10 microg cefoxitin disc and overnight incubation in ambient air at 35-37 degrees C . RESULTS: For S . aureus, both cefoxitin discs performed with high accuracy on both media . The sensitivity and specificity for the following proposed interpretive zone diameters were: ISA 5 microg, R < 14 mm (99.5% and 98.1%); ISA 10 microg, R < 22 mm (99.5% and 98.1%); MH 5 microg, R < 12 mm (99.7% and 98.1%); and MH 10 microg, R < 18 mm (99.5% and 98.9%), respectively . All four variants were superior to oxacillin using the former SRGA methodology . In CoNS, a substantial overlap was seen for all variants . However, by avoiding primary interpretation in the overlapping interval, highly accurate results could be obtained for 81%, 80%, 91% and 97% of the isolates, respectively . CONCLUSION: For S . aureus, cefoxitin 5 and 10 microg discs performed with high accuracy on both ISA and MH using semi-confluent growth and standard incubation conditions . With the introduction of a defined interval in which primary interpretation should be avoided, the method could also be used for CoNS.

J Antimicrob Chemother . 2005 Jan 13; {Epub ahead of print}
Enhanced resistance to erythromycin is conferred by the enterococcal msrC determinant in Staphylococcus aureus; Reynolds E et al.; The msrC gene, found on the chromosome of Enterococcus faecium, shares a high degree of similarity with the staphylococcal erythromycin resistance determinant msr(A) . The enterococcal determinant was cloned into Staphylococcus aureus to determine whether msrC could confer antibiotic resistance in staphylococci . A shuttle vector comprising pBluescript and pSK265 was used to introduce multiple copies of msrC into S . aureus RN4220 . The integration vector pCL84 was employed to insert a single copy of msrC into the S . aureus chromosome . MICs were determined by the broth microdilution method . Expression of msrC from both chromosomal and plasmid loci in erythromycin-susceptible S . aureus RN4220 (MIC 0.25 mg/L) gave rise to enhanced protection against erythromycin, with an MIC of 32-64 mg/L for S . aureus RN4220 containing msrC in multiple copies and an MIC of 16-64 mg/L with msrC inserted as a single copy in the S . aureus chromosome . MsrC mediates high-level resistance to erythromycin in S . aureus.

J Microbiol Methods, 2005 Mar, 60(3), 413 - 6
Rapid detection of methicillin resistance in teicoplanin-resistant coagulase-negative staphylococci by a penicillin-binding protein 2' latex agglutination method; Knausz M et al.; Thirty-five clinical isolates of coagulase-negative staphylococci with decreased glycopeptide sensitivity were examined by a penicillin-binding protein (PBP2') latex agglutination (LA) test and were compared to the detection of the mecA gene by PCR, and oxacillin susceptibility determined minimum inhibitory concentrations . The latex test demonstrated high sensitivity and specificity for detecting methicillin resistance in coagulase-negative staphylococci after PBP2' induction with oxacillin.

Heart Lung, 2005 Jan-Feb, 34(1), 69 - 71
Methicillin-resistant Staphylococcus aureus prosthetic aortic valve endocarditis with paravalvular abscess treated with daptomycin; Mohan SS et al.; Prosthetic valves have been used extensively for severe cardiac valvular dysfunction for the past 3 decades . Prosthetic cardiac valves may be infected with organisms causing bacteremia, particularly gram-positive cocci . Staphylococcus epidermidis (coagulase negative staphylococci) and Staphylococcus aureus , both methicillin-susceptible S . aureus and methicillin-resistant S . aureus (MRSA) strains, are the most frequent pathogens causing prosthetic valve endocarditis (PVE) . Vancomycin has been the cornerstone of therapy for serious MRSA infections including bacteremia and endocarditis . Clinicians have noted that MRSA bacteremias treated with vancomycin often fail to clear even with prolonged therapy . Persistent or prolonged MRSA bacteremia unresponsive to vancomycin therapy has led to the treatment of these infections by other agents, that is, quinupristin, dalfopristin, linezolid, or daptomycin . These antibiotics have been found particularly useful in treating MRSA bacteremias unresponsive to vancomycin therapy . We report a case of a patient who presented with MRSA PVE complicated by perivalvular aortic abscess with persistent MRSA bacteremia unresponsive to vancomycin therapy . The patient's MRSA bacteremia was cleared with daptomycin therapy (6 mg/kg/d) . Because the patient refused surgery, daptomycin therapy was continued in hopes of curing the endocarditis and sterilizing the perivalvular aortic abscess . Transesophageal echocardiogram revealed a decrease in abscess in the aortic perivalvular abscess after 1 week of daptomycin therapy . The patient made an uneventful recovery . The cure of PVE and perivalvular abscesses usually requires removal of the prosthetic device and abscess drainage . In this case, in which surgery was not an option, medical therapy of PVE and a decrease in size of the aortic perivalvular abscess were accomplished with daptomycin therapy . Daptomycin is an alternative to vancomycin therapy in patients with prolonged or persistent MRSA bacteremia secondary to endocarditis or abscess.

Int J Hematol, 2004 Dec, 80(5), 467 - 9
Second transplantation from HLA 2-loci-mismatched mother for graft failure due to hemophagocytic syndrome after cord blood transplantation; Tanaka T et al.; A 7-year-old girl with acute myelogenous leukemia with multilineage dysplasia received unrelated cord blood transplantation but developed hemophagocytic syndrome (HPS) after sepsis with methicillin-resistant coagulase-negative staphylococci before engraftment . Bone marrow aspiration on day 20 revealed a markedly increased number of activated macrophages showing hemophagocytosis . The presence of donor-type chimera in the bone marrow was confirmed at that time . We therefore quickly started immunosuppressive and antibacterial treatment . Although her condition gradually improved, the patient suffered graft failure due to HPS . She received peripheral blood stem cell transplantation from her HLA 2-loci-mismatched mother on day 54 and continued in complete remission 12 months after the second transplantation . The results in this case suggested that because of fetomaternal microchimerism it may be useful to select an HLA-haploidentical mother as a backup donor for stem cell transplantation.

Int J Clin Pract, 2004 Dec, 58(12), 1112 - 4
Slime factor positivity in coagulase negative staphylococci isolated from nasal samples of haemodialysis patients; Altoparlak U et al.; Polysaccharide slime seems to be the most important factor by which coagulase negative staphylococci (CNS) strains adheres and colonises catheters . The aim of this study was to determine the prevalence of slime-producing CNS strains isolated from nasal samples of patients on haemodialysis and of healthy persons as a control . Nasal cultures were performed for 131 haemodialysis patients and 56 healthy persons . CNS strains were isolated from 86 of 131 patients (72.9%), and 46 of 56 healthy persons (82.1%) . Twenty-four (27.9%) of the 86 CNS strains tested in the patient group and four (8.7%) of the 46 CNS strains in the control group were slime factor positive . There was a significant difference (p<0.01) in slime production between CNS strains isolated from haemodialysis patients and from control group . The detection of slime-producing coagulase-negative staphylococcus carriage in haemodialysis patients may prevent dialysis catheter-related coagulase-negative staphylococcal infections.

Oral Health Prev Dent, 2003, 1(1), 29 - 35
Propolis extract as an adjuvant to periodontal treatment; Gebaraa EC et al.; PURPOSE: The aim of this study was to evaluate the effect of subgingival irrigation with propolis extract by clinical and microbiological parameters . MATERIALS AND METHODS: Twenty patients diagnosed with chronic periodontitis presenting three non-adjacent teeth with deep pockets were selected . After scaling and root planing, the selected periodontal sites were submitted to one of the following treatments: irrigation with a hydro alcoholic solution of propolis extract twice/week for two weeks (group A); irrigation with a placebo twice/week for two weeks (group B); or no additional treatment (C) . Subgingival plaque sampling and scaling and root planing were performed two weeks after clinical data recording . Two weeks later irrigation procedures were started (Baseline) . Microbiological and clinical data were collected at baseline, and after 4, 6 and 24 weeks . RESULTS: A decrease in total viable counts of anaerobic bacteria (p=0.007), an increase in the proportion of sites with low levels (< or = 10(3) cfu/mL) of Porphyromonas gingivalis (p=0.005), and a decrease in the number of sites with detectable presence of yeasts (p=0.000) were observed in group A sites when compared to group B and C sites . Propolis treatment did not lead to an increase in organisms such as coagulase positive Staphylococci and Pseudomonas spp . 24 weeks after treatment there was an increased proportion of sites showing probing depth (PD) < or = 3 mm in Group A sites . CONCLUSION: Subgingival irrigation with propolis extract as an adjuvant to periodontal treatment was more effective than conventional treatment both by clinical and microbiological parameters.

APMIS, 2004 Dec, 112(11-12), 815 - 37
Genetic methods for detection of antimicrobial resistance; Sundsfjord A et al.; Sundsfjord A, Simonsen GS, Haldorsen BC, Haaheim H, Hjelmevoll SO, Littauer P, Dahl KH . Genetic methods for detection of antimicrobial resistance . APMIS 2004;112:815-37.Accurate and rapid diagnostic methods are needed to guide antimicrobial therapy and infection control interventions . Advances in real-time PCR have provided a user-friendly, rapid and reproducible testing platform catalysing an increased use of genetic assays as part of a wider strategy to minimize the development and spread of antimicrobial-resistant bacteria . In this review we outline the principal features of genetic assays in the detection of antimicrobial resistance, their advantages and limitations, and discuss specific applications in the detection of methicillin-resistant Staphylococcus aureus, glycopeptide-resistant enterococci, aminoglycoside resistance in staphylococci and enterococci, broad-spectrum resistance to beta-lactam antibiotics in gram-negative bacteria, as well as genetic elements involved in the assembly and spread of antimicrobial resistance.

J Clin Microbiol, 2005 Jan, 43(1), 179 - 85
First report of vancomycin-resistant staphylococci isolated from healthy carriers in Brazil; Palazzo IC et al.; Reduced susceptibility or resistance to vancomycin has been reported among clinical isolates of staphylococci in previous studies . In the present study we report on the isolation of four vancomycin-resistant staphylococcal strains from healthy carriers inside and outside the hospital environment . These carriers did not receive treatment with any antibiotic . All coagulase-negative staphylococcal strains showed variable levels of resistance to several antimicrobial agents, including oxacillin, and unstable resistance to vancomycin, with decreased vancomycin MICs (<4 mg/liter) after 10 days of passage in a nonselective medium . However, exposure of these revertants to vancomycin selected staphylococcal strains resistant to vancomycin at very high frequencies (10(-2) and 10(-3)) . The vancomycin resistance in these staphylococcal strains was not mediated by the van gene . The cell wall of the staphylococcal strains studied became thickest after culture in medium containing vancomycin, and the differences in cell wall thickness were statistically significant (P < 0.001) . Thus, the thickening of the cell wall in these staphylococcal strains may be an important contributor to vancomycin resistance.

Vnitr Lek, 2004 Oct, 50(10), 786 - 92
{Kikuchi-Fujimoto disease (histiocytic necrotizing lymphadenitis) . Case study and a literature review}; Olejarova M et al.; Kikuchi-Fujimoto disease is a rare feverish disease characterised by lymphadenopathy, the most frequently cervical, exanthem, arthralgias and arthritis . It affects especially young women . Patients have high erythrocyte sedimentation rate (ES) and leucopenia, antibodies are missing . Course of the disease is usually very benign and can subside spontaneously . However, clinical picture is usually very dramatic and can suggest infectious, autoimmune or malign systemic disease; also association with some of autoimmune diseases was described . Its occurrence is sporadic in all the world, the most of cases were seen in Asia, in the Czech Republic it has not been yet described . Therapy consists in antibiotics administration followed with corticoid therapy and usually can restore patients to perfect health . However, exacerbations have also been described . We describe a case of a 60 year old man, a past top sportsman, who has never been seriously ill except sport traumas and prosthesis implantation for coxarthritis reasons . The last two years he has suffered from exanthem and leucopenia of an unclear origin . In May 2002 he become feverish and arthritis, lymphadenopathy, splenomegalia and exanthem progression, high ES rate and high serum level of C-reactive protein (CRP) appeared in him . His condition was first evaluated as septic condition (founded staphylococci in two blood cultures), however, cause of potential sepsis has not been identified . The patient was treated with antibiotics with improvement of his total health condition after second treatment regiment . A neck node biopsy was done because of suspicion on lymphoprolipherative disease and histiocytic necrotizing lymphadenitis of Kikuchi type was found . Autoantibodies assessment was completely negative . After antibiotic and corticoid therapies his clinical condition quite quickly standardized and ES rate and serum CPR level decreased . 4 month after lowering the dose of prednisolon a temporary exacerbation of the disease appeared and again disappeared after increasing the dose of corticoid.

J Infect Dis, 2005 Feb 1, 191(3), 435 - 43 Epub 2004 Dec 28.
Intravital Fluorescence Microscopy: A Novel Tool for the Study of the Interaction of Staphylococcus aureus with the Microvascular Endothelium In Vivo; Laschke MW et al.; Background . The ability of Staphylococcus aureus to adhere to endothelial cells is a major prerequisite for the tissue-invasive stage of bacterial infection.Methods . To develop a model for the study of endothelial attachment and detachment kinetics of S . aureus within the host's microvasculature in vivo, we labeled inactivated staphylococci with fluorescein isothiocyanate and investigated their interaction with the vascular endothelium of arterioles, capillaries, and venules in the dorsal skin-fold chamber of untreated and tumor necrosis factor (TNF)- alpha -treated hamsters by use of intravital fluorescence microscopy.Results . During the first 20 min after injection, >99% of the bacteria were removed from the microvascular bloodstream . In parallel, single bacteria and bacterial clusters adhered to the endothelial lining of postcapillary venules and to nutritive capillaries . Bacterial adherence to the endothelium of arterioles was only rarely observed . TNF- alpha treatment significantly accelerated bacterial clearance and resulted in a significant increase of venular, but not arteriolar and capillary, bacterial adherence, indicating the venular endothelium to be the target structure for bacterial recruitment.Conclusion . The insights into host-pathogen interaction gained with this new in vivo model offer highly promising novel aspects of the understanding of infections caused by S . aureus.

Zhonghua Yi Xue Za Zhi, 2004 Nov 17, 84(22), 1867 - 71
{Comparison of pharmacokinetics/pharmacodynamics of cefdinir, cefpodoxime proxetil and cefaclor against common bacteria of community acquired infections.}; Xiao YH et al.; OBJECTIVE: To compare the pharmacokinetics/pharmacodynamics property of cefdinir, cefpodoxime proxetil and cefaclor against common bacteria of community acquired infections and evaluate the recommended regimens . METHODS: The antibacterial activities of 3 agents against 238 clinical isolates were determined by standard agar dilution test and the pharmacokinetics of these antibiotics in male healthy volunteers were conducted in Latin-square manner . The time over MIC (T > MIC) of serum antibiotic concentrations were calculated with pharmacokinetic equation and MIC . RESULTS: The value of MIC(90)s cefdinir against these bacterial strains except penicillin non-sensitive pneumococci were 0.031 - 1 mg/L . Cefpodoxime held similar antibacterial activity with cefdinir, but was less potent against staphylococci . Cefaclor had much higher MIC values than other two drugs . After oral administration of 250 mg cefaclor, the drug concentration quickly reached peak concentration of 4.95 mg/L +/- 2.41 mg/L and the eliminative half time was 0.69 h +/- 0.6 h; the Tmax, Cmax and T(1/2)beta of cefdinir and cefpodoxime after oral administration of 100 mg were 2.5 h +/- 0.48 h, 0.81 mg/L +/- 0.19 mg/L, 1.73 h +/- 0.3 h and 2.38 h +/- 0.43 h, 1.12 mg/L +/- 0.28 mg/L, 1.92 h +/- 0.55 h, respectively . T > MIC of cefdinir in thrice daily administration were longer than 40% of medication interval against most of the tested isolates; no T > MIC period was found in cefpodoxime against staphylococci and the T > MICs of cefaclor after 250 mg oral administration were shorter than expected values against most bacteria . CONCLUSION: With powerful antibacterial activity, the T > MICs of cefdinir after 100 mg oral administration can meet with the clinical requirement in most infections; PK/PD value of cefpodoxime proxetil against staphylococci is lower than expectancy and 250 mg cefaclor 3 times daily is not enough to the treatment of common community acquired infections, the regimens of cefpodoxime proxetil and cefclor should be furtherly optimized.

J Occup Environ Hyg, 2004 Oct, 1(10), 639 - 47
Evaluation and determinants of airborne bacterial concentrations in school classrooms; Bartlett KH et al.; A survey of 39 elementary schools was undertaken to determine indoor air concentrations of bioaerosols within a coastal, temperate climatic zone in British Columbia, Canada . This article reports the results for airborne bacteria . Determinants of exposure were grouped into environmental (outdoor temperature, relative humidity, season, weather), ventilation and comfort parameter (indoor relative humidity, temperature, indoor CO2 concentration, indoor fungal concentration), and occupancy (number of occupants, activity levels, occupancy patterns) variables . Regression modeling was used to evaluate the association between these factors and measured concentrations of indoor mesophilic bacteria . Naturally ventilated rooms (47% of the total rooms surveyed) had higher bacterial counts than mechanically ventilated rooms (geometric mean 325 vs . 166 CFU/m3, respectively, p < 0.001) . In univariate analyses, bacterial counts were negatively correlated with supply and exhaust flow rates, air exchange rates, and the percentage of the day that occupants spent quietly sitting at their desks . Analysis of bacterial groups indicated various sources of the bacterial aerosol, with micrococci and staphylococci closely associated with occupancy variables, Bacillus with site and occupancy, and coryneform bacteria with site variables only . Approximately 60% of the variance in the outcome measurement of total bacteria was accountedfor by indoor CO2, lower air exchange rate, the age of the building, signs of current or old moisture stains, room volume, indoor relative humidity, and occupant activity level in a multiple linear regression model, with ventilation factors accounting for 40% of the variance.

Diagn Microbiol Infect Dis, 2005 Jan, 51(1), 57 - 62
Evaluation of alternative disk diffusion methods for detecting mecA-mediated oxacillin resistance in an international collection of staphylococci: Validation report from the SENTRY antimicrobial surveillance program; Pottumarthy S et al.; To validate the current National Committee for Clinical Laboratory Standards recommendations of the cefoxitin disk as a preferred surrogate marker to detect oxacillin resistance in staphylococcal isolates, 304 staphylococcal isolates originating from 49 sites in 16 countries in the SENTRY Antimicrobial Surveillance Program (2003) were tested . Two hundred three Staphylococcus aureus and 101 coagulase-negative staphylococci (CoNS), of which >95% were bloodstream isolates, were evaluated by comparing the results of the National Committee for Clinical Laboratory Standards broth microdilution method for oxacillin with those of the disk diffusion test using oxacillin, cefoxitin and ceftizoxime disks . Discrepancies were resolved using the PBP2a latex agglutination test . For S . aureus, the cefoxitin disk performed without interpretive error followed by the ceftizoxime disk (1% major and 0.5% minor errors; >/=20 mm = susceptible); use of the oxacillin disk test had the highest error rates with 4.4% major and 1.5% minor errors, whereas the oxacillin minimal inhibitory concentration (MIC) test was 99.0% accurate . For CoNS, the oxacillin disk test had the highest error rate with 4.0% major errors, followed by the cefoxitin (3.0% major error rate) and the ceftizoxime (1% very major and 1% minor error: >/=20 mm = susceptible) disk tests . The oxacillin MIC test was also 99.0% accurate for CoNS testing . Modification of the ceftizoxime disk diffusion breakpoints for CoNS resulted in complete intermethod categorical agreement . The overall accuracy of the four tests was as follows: modified ceftizoxime disk (99.3%) > oxacillin MIC = cefoxitin disk (99.0%) > current ceftizoxime disk (98.4%) > oxacillin disk (94.7%) . In conclusion, these results confirm the superior performance characteristics of cefoxitin and ceftizoxime disk tests as surrogate markers to detect oxacillin resistance; by using an international collection of clinically significant staphylococcal isolates, we also demonstrate its wide global application.

Diagn Microbiol Infect Dis, 2005 Jan, 51(1), 13 - 7
Rapid detection of mecA and nuc genes in staphylococci by real-time multiplex polymerase chain reaction; Costa AM et al.; A multiplex real-time polymerase chain reaction (RT-PCR) targeting the mecA and nuc genes was developed for the detection of methicillin resistance and identification of Staphylococcus aureus . Novel mecA and nuc primers and fluorescence resonance energy transfer hybridization probes specific for the mecA and nuc genes were evaluated . The assay was performed using the LightCycler system (Roche Molecular Biochemicals, Mannheim, Germany) and evaluated against the traditional gel-based multiplex PCR (PCR-gel) method currently used at Royal Perth Hospital . Clinical isolates (n = 222) and isolates from a culture collection library (n = 206) were tested by both assays in parallel . The RT-PCR assay was 100% sensitive and specific for the detection of methicillin resistance and for the identification of S . aureus when compared with the PCR-gel assay . Results from the RT-PCR assay showed 5 isolates with lower efficiency fluorescence curves for the nuc gene PCR fragment . DNA sequencing showed mutations within the region of the probe-binding sites compared with the reference strain . The results of the RT-PCR assay were available within 2 h . This rapid mecA/nuc RT-PCR assay is a suitable and practical tool for the routine detection of methicillin resistance and identification of S . aureus, which can be easily incorporated into the diagnostic molecular microbiology laboratory work flow.

Rhinology, 2004 Dec, 42(4), 213 - 8
Microbiology of chronic hyperplastic sinusitis; Kostamo K et al.; BACKGROUND: Patients with chronic hyperplastic sinusitis (CHS) form a heterogeneous group with similar symptoms and similar treatment despite of possible different mechanisms behind the disease . In the present study we focused on the microbiological findings in CHS and compared these results to the patient history in order to find out a possible explanation for the aetiology and chronicity of CHS . METHODS: In 30 patients the sinus mucus was collected under endoscopic sinus surgery . Samples from 20 healthy volunteers were collected by nasal lavage . Eosinophil staining, bacterial culturing and fungal staining and culturing were done . Histological samples were obtained from all patients . RESULTS: Bacterial cultures were positive in 93% of the patients compared to 70% in controls . Staphylococcus aureus and coagulase-negative Staphylococci were the two most common findings in both groups . A total of seven patients had positive fungal finding . The only fungal genus found was Aspergillus . In the control group no samples were positive for fungi . CONCLUSIONS: Microbiological findings do not seem to explain the chronic course of CHS, but fungi may play some part in the pathophysiology of the disease . These results may be more a reflection of a change in the environment in the paranasal sinuses and a change in normal flora than the actual cause of CHS.

Ann Pharmacother . 2004 Dec 28; {Epub ahead of print}
Antibiotic Lock Technique: A Review of the Literature (February); Segarra-Newnham M et al.; OBJECTIVE: To review the literature on the use of the antibiotic lock technique (ALT) as a treatment option for patients with highly needed catheters . DATA SOURCES: MEDLINE and International Pharmaceutical Abstracts were searched (1980-August 2004) . Search terms included antibiotic lock, catheter infection, and topical treatment . STUDY SELECTION AND DATA EXTRACTION: Articles describing use of ALT in the treatment of catheter infections in humans and studies evaluating in vitro stability of antibiotics were included . DATA SYNTHESIS: ALT has been used in patients with highly needed catheters, usually for parenteral nutrition, cancer chemotherapy, or dialysis . Catheters are considered highly needed when removal is not feasible or desirable due to lack of alternative injection sites for required therapy . Success rates in saving the infected catheter have been variable and may depend on the infecting organism . In addition, there are conflicting data in terms of compatibility of antibiotics with heparin solutions . CONCLUSIONS: Consensus appears to be that the ALT can be tried for patients with highly needed catheters when infection with coagulase-negative staphylococci is documented and no systemic signs of sepsis, such as hypotension, are evident . Most of these patients are likely to need systemic therapy as well . Infection of the catheter associated with systemic gram-negative bacteremia or fungemia will most likely require removal of the catheter to prevent systemic complications . Additional research with the ALT is warranted given unanswered questions.

Int J Food Microbiol, 2005 Jan 15, 98(1), 73 - 9
Coagulase-positive Staphylococci and Staphylococcus aureus in food products marketed in Italy; Normanno G et al.; Staphylococcus aureus is a very common organism capable of producing several enterotoxins (SEs) that cause intoxication symptoms of varying intensity in humans when ingested through contaminated food . This paper reports the results of an investigation on the presence of Coagulase-Positive Staphylococci (CPS) and S . aureus in several food products marketed in Italy and on food contact surface swabs sampled from the food industry . A total of 11,384 samples were examined and 1971 of them (17.3%) were found to contain CPS . The assays performed on 541 CPS strains led to the identification of 537 S . aureus strains on which characterization of type A, B, C and D staphylococcal enterotoxins (SEA, SEB, SEC and SED) was performed . A total of 298 S . aureus strains (55.5%) produced one or more SEs: 33.9% of the strains produced SEC, 26.5% SEA, 20.5% SEA+SED, 13.4% SED, 2.7% SEB, 1.7% SEA+SEB, 0.7% SEC+SED and 0.3% produced SEA+SEC and SEB+SEC . The investigation highlighted that these organisms are very common and constitute a potential risk for consumers' health.

Lett Appl Microbiol, 2005, 40(1), 24 - 9
The killing effect of cryptolepine on Staphylococcus aureus; Sawer IK et al.; Abstract i.k . sawer, m.i . berry and j.l . ford . 2004.Aim: This study was undertaken to further examine the antimicrobial actions of the alkaloid cryptolepine . Methods and Results: The minimum inhibitory concentration (MIC) of cryptolepine against Staphylococcus aureus was determined using the broth dilution method . Time-kill kinetics and scanning electron microscopy (SEM) techniques were employed to monitor the survival characteristics and the changes in morphologies respectively of staphylococci in the presence of cryptolepine . A notable antistaphylococcal activity was recorded for cryptolepine (MIC against S . aureus NCTC 10788 = 5 mug ml(-1)) . Cryptolepine appears to have a lytic effect on S . aureus as seen in SEM photomicrographs following 3, 6 or 24 h treatment with 4X MIC, i.e . 20 mug ml(-1) of cryptolepine . The surface morphological appearance of the staphylococcal cells was also altered . The lytic effect appeared to coincide with low viable counts recorded in survival curves following treatment with cryptolepine . Significance and Impact of the Study: These findings demonstrate that lysis occurs when susceptible organisms are exposed to cryptolepine.

J Vet Med B Infect Dis Vet Public Health, 2004 Dec, 51(10), 449 - 54
Microbiological Features of Staphylococcus schleiferi subsp . coagulans, Isolated from Dogs and Possible Misidentification with Other Canine Coagulase-positive Staphylococci; Zdovc I et al.; Summary Staphylococcus schleiferi subsp . coagulans has only rarely been isolated and identified from the external auditory meatus of dogs suffering from external otitis . Its morphological and basic biochemical characteristics are of relatively little value for identification, as it phenotypically resembles another coagulase-positive staphylococci (CPS) and, consequently, may be easily misidentified as S . intermedius or even as S . aureus . In the present work, differentiation of S . schleiferi ssp . coagulans was therefore based on specific biochemical and genetic methods . All the strains were evaluated with the following commercial methods: Api Staph System (bioMerieux, Marcy l'Etoil, France), BBL Crystal Identification Systems (Gram-Positive ID Kit and Rapid Gram-Positive ID Kit; Becton Dickinson), and GEN-PROBE((R)) AccuProbe, Staphylococcus aureus identification test (bioMerieux) . Gram-Positive ID System/GP database includes the broadest range of staphylococcal species and correctly identifies the majority of strains important in veterinary medicine . Therefore, it is an acceptable alternative to conventional methods for identification of canine staphylococcal isolates . Reliable differentiation of S . aureus from S . schleiferi ssp . coagulans and S . intermedius was feasible with AccuProbe for S . aureus, which gave positive results only for S . aureus; all other CPS tested were negative.

J Small Anim Pract, 2004 Dec, 45(12), 591 - 7
Methicillin-resistant Staphylococcus aureus in dogs and cats: an emerging problem?
Duquette RA, Nuttall TJ.
There is concern over transmission of methicillin-resistant Staphylococcus aureus (MRSA) between animals and humans . The spread of hospital-acquired and community-acquired MRSA is a major challenge in human medicine . MRSA is rarely isolated from animals but methicillin resistance occurs in staphylococci that are more prevalent in animals . MRSA infections in animals are uncommon and most are associated with exposure to medical hospitals, extensive wounds, prolonged hospitalisation and immunosuppression . The risk to human health appears to be small but a survey of methicillin-resistant staphylococci in animals is required . Thorough investigation of possible zoonotic infections to establish linkage is encouraged . Medical and veterinary staff should appreciate that animals can carry MRSA, cooperate in eliminating infections and monitor animals in medical environments . Veterinary clinics should implement guidelines for dealing with MRSA . Responsible antibiotic use should minimise the spread of antibiotic resistance but a UK monitoring scheme is desirable.

Pathol Biol (Paris), 2004 Dec, 52(10), 575 - 578

Laurain C, Durand PY, Albert M, Weber M, Kessler M, Chanliau J, Dailloux M.
The purpose of this study was to analyse the microbiological characteristics of infectious peritonitis in patients undergoing continuous ambulatory peritoneal dialysis . This study was conducted at the CHU Nancy from 1999 to 2002 . The diagnosis of peritonitis was based on cloudy peritoneal effluent (>100 cells per mm(3)) with an elevated leukocyte count (>50%), on isolation of bacteria or fungi and on symptoms such as abdominal discomfort or pain . The majority of infections associated with continuous ambulatory peritoneal dialysis were caused by Gram-positive bacteria (68%), Gram-negative bacteria (31%), and Candida (1%) . The coagulase-negative staphylococci were the most common cause of peritonitis . The antibiotic sensitivity of species corresponded to community-acquired isolation.

J Infect Dis, 2005 Jan 1, 191(1), 138 - 44 Epub 2004 Nov 30.
Corticoids normalize leukocyte production of macrophage migration inhibitory factor in septic shock; Maxime V et al.; BACKGROUND: A regulatory loop between macrophage migration inhibitory factor (MIF) and glucocorticoids has been characterized in animal models . Renewed interest in glucocorticoid treatment for septic shock offers an opportunity to analyze this regulatory loop in humans . METHODS: We investigated the ex vivo release of MIF by peripheral blood mononuclear cells (PBMCs) sampled from glucocorticoid-treated and -untreated patients with septic shock . Blood was obtained, before glucocorticoid treatment, and within the first day of treatment, from patients with septic shock who required treatment with moderate doses of hydrocortisone and fludrocortisone . RESULTS: PBMCs from patients contained significantly higher amounts of MIF than cells from healthy control subjects . In culture, spontaneous release of MIF and release induced by lipopolysaccharide (LPS), heat-killed staphylococci, and red blood cell lysates were significantly higher in patients than in control subjects . PBMCs from patients treated with glucocorticoids showed a lower release of MIF in response to LPS, heat-killed Escherichia coli, and peptidoglycan than did PBMCs from untreated patients and showed levels similar to PBMCs from healthy control subjects . CONCLUSION: To our knowledge, MIF is the first proinflammatory cytokine in which ex vivo release by circulating cells is enhanced during sepsis . Glucocorticoid treatment normalized the release of MIF by circulating PBMCs from patients with septic shock.

J Med Microbiol, 2004 Dec, 53(Pt 12), 1195 - 9
Evaluation of phenotypic methods for methicillin resistance characterization in coagulase-negative staphylococci (CNS); Caierao J et al.; Coagulase-negative staphylococci (CNS) are the major cause of nosocomial infections . Methicillin-resistant strains are particularly important because they narrow therapeutic options . Detecting methicillin resistance among CNS has been a challenge for years . The objective of this study was to determine the accuracy of an agar screening test (0.6 and 4 microg oxacillin ml(-1)), disc diffusion and the automated MicroScan system to characterize methicillin resistance among CNS . One hundred and seventy five strains were analysed: 41.1 % Staphylococcus epidermidis and 59.9 % other species; 69.1 % were mecA-positive . The results showed that the methods have optimal correlation with the detection of mecA gene for S . epidermidis, Staphylococcus hominis and Staphylococcus haemolyticus . However, accuracy of the tests is impaired when less common species are analysed . The only 100 % accurate test was agar screening with 4 microg oxacillin ml(-1).

Pharmacotherapy, 2004 Dec, 24(12 Pt 2), 203S - 15S
Resistance to antimicrobial agents: an update; Rybak MJ; Decades of overuse and misuse of antibiotics have turned the resistance problem into a crisis . Preventive and corrective measures are urgently needed . This article presents a broad overview of the status of antimicrobial resistance . Resistance in key bacterial pathogens such as enterococci, staphylococci, pneumococci, and gram-negative bacilli; resistance to fluoroquinolones, third-generation cephalosporins, and the carbapenems; and mechanisms of resistance are discussed . The article also reviews the adverse impact of resistance on outcomes for patients with nosocomial infections . Finally, a brief overview of how the medical community can face its moment of truth is presented.

Biomaterials, 2005 May, 26(15), 2247 - 54
Characterisation of antibacterial copper releasing degradable phosphate glass fibres; Abou Neel EA et al.; Phosphate-based glass fibres (PGF) of the general formula Na(2)O-CaO-P(2)O(5) are degradable in an aqueous environment, and therefore can function as antibacterial delivery systems through the inclusion of ions such as copper . In this study, PGF with varying amounts of copper oxide (CuO) were developed for potential uses in wound healing applications . PGF with 0, 1, 5 and 10mol% CuO were produced with different diameters and characterised in terms of structural and antibacterial properties . The effect of CuO and fibre pulling speed on the glass properties were investigated using rapid differential scanning calorimetry, differential thermal analysis and X-ray diffraction . The effect of two fibre diameters on short-term (3h) attachment and killing against Staphylococcus epidermidis were investigated and were related to their rate of degradation in deionised water, as well as copper ion release measured using ion chromatography . Thermal analysis showed that there was a significant increase in the PGF glass transition temperature as the CuO content increased . There was a significant decrease in the rate of degradation with increasing CuO content and an increase in fibre diameter . Over 6h, both the amount and rate of copper ions released increased with CuO content, as well as a reduction in fibre diameter thus increasing the surface area to volume ratio . There was a decrease in the number of viable staphylococci both attached to the CuO-containing fibres and in the surrounding environment.

J Clin Microbiol, 2004 Dec, 42(12), 5739 - 44
Simultaneous detection of Staphylococcus aureus and coagulase-negative staphylococci in positive blood cultures by real-time PCR with two fluorescence resonance energy transfer probe sets; Sakai H et al.; A real-time PCR assay that uses two fluorescence resonance energy transfer probe sets and targets the tuf gene of staphylococci is described here . One probe set detects the Staphylococcus genus, whereas the other probe set is specific for Staphylococcus aureus . One hundred thirty-eight cultured isolates, which contained 41 isolates of staphylococci representing at least nine species, and 100 positive blood cultures that contained gram-positive cocci in clusters were tested . This assay was 100% sensitive and 100% specific for the detection of the Staphylococcus genus and of S . aureus.

Acta Microbiol Immunol Hung, 2004, 51(3), 371 - 84
Different staphylococcal strains elicit different levels of production of T-helper 1-inducing cytokines; Buzas K et al.; Cytokine production has been implicated in the pathogenic mechanisms of infections caused by the staphylococci, since these bacteria may act as strong cytokine inducers . To gain deeper insight into the Th1 immune response activated by these bacteria, we have analyzed the interferon (IFN), interleukin-12 (IL-12) and IL-18-inducing activities of different Staphylococcus aureus (S . aureus), S . epidermidis and S . saprophyticus strains in human monocytes and murine bone marrow macrophages . A large majority of the S . aureus strains elicited the simultaneous production of IL-12 p70 and IFN-alpha in the human monocytes, while the S . epidermidis and S . saprophyticus strains induced only a low level of production, if any, of these cytokines . Furthermore, a majority of the S . aureus strains induced significantly higher IL-12 p70 and IL-18 titers in the murine bone marrow macrophages than did the S . epidermidis and S . saprophyticus strains . As IL-12, IL-18 and IFN-alpha stimulate Th1 differentiation synergistically, we suggest that S . aureus strains bias the immune response toward a Th1 phenotype, whereas S . epidermidis and S . saprophyticus strains provide a weaker stimulus for the production of Th1-inducing cytokines, and accordingly possibly elicit a less extensive Th1-associated adaptive immunity.

East Mediterr Health J, 2003 Jan-Mar, 9(1-2), 185 - 90
Use of thermonuclease testing to identify Staphylococcus aureus by direct examination of blood cultures; Kaplan NM; Blood cultures submitted to the Clinical Microbiology Laboratory, Queen Alia Military Hospital, Amman during 1999-2001 were examined to evaluate thermonuclease testing for identifying Staphylococcus aureus in blood culture broths growing gram-positive cocci . Of 170 cultures studied, 129 yielded gram-positive staphylococci and 41 yielded other gram-positive cocci . Toluidine blue-deoxynucleic acid agar plates were used to test for thermonuclease activity . Standard tube coagulase tests were performed on the isolates . Direct detection of thermonuclease activity in 76 blood culture broths containing gram-positive staphylococci showed 100% correlation with subsequent tube coagulase tests . The thermonuclease test provides a fast, specific and reliable confirmation of S . aureus bacteraemia by direct examination of blood culture broths that contain gram-positive cocci . This allows for timely, optimal antibiotic therapy.

Antimicrob Agents Chemother, 2004 Dec, 48(12), 4754 - 61
Antistaphylococcal activity of WCK 771, a tricyclic fluoroquinolone, in animal infection models; Patel MV et al.; WCK 771, the arginine salt of S-(-)-nadifloxacin, was evaluated in animal models of staphylococcal infection and in vitro . For 302 methicillin-susceptible strains the MIC at which 50% of isolates are inhibited (MIC50) and the MIC90 of WCK 771 were 0.03 and 0.03 microg/ml, respectively, and for 198 methicillin-resistant strains the MIC50 and the MIC90 were 0.5 and 1.0 microg/ml, respectively . All methicillin-susceptible staphylococci were quinolone susceptible, and almost all methicillin-resistant staphylococci were quinolone resistant . WCK 771 was more potent than moxifloxacin, trovafloxacin, levofloxacin, and ciprofloxacin and had potency comparable to that of clinafloxacin . Only WCK 771 and clinafloxacin demonstrated strong potencies against vancomycin-intermediate Staphylococcus aureus strains (MICs = 1 microg/ml) . WCK 771 is not a substrate of the NorA pump, as evident from the lack of an effect of reserpine on the MICs and similar protective doses against infections caused by efflux-positive and -negative staphylococci . WCK 771 was effective by both the oral and the subcutaneous routes in mice infected intraperitoneally with quinolone-susceptible methicillin-susceptible S . aureus (MSSA) strains . For infections caused by quinolone-resistant methicillin-resistant S . aureus (MRSA) strains, the activity of WCK 771 administered subcutaneously was superior to those of trovafloxacin and sparfloxacin, with a 50% effective dose range of 27.8 to 46.8 mg/kg of body weight . The activity of WCK 771 was superior to those of moxifloxacin, vancomycin, and linezolid in a mouse cellulitis model of infection caused by one MSSA and two MRSA strains, with effective doses of 2.5 and 5 mg/kg for the MSSA strain and 10-fold higher effective doses for MRSA strains . WCK 771, like vancomycin and linezolid, eradicated MRSA from mouse liver, spleen, kidney, and lung when it was administered subcutaneously at a dose of 50 mg/kg for four doses . These studies have demonstrated the effectiveness of WCK 771, administered orally and parenterally, for the treatment of diverse staphylococcal infections in mice, including those caused by quinolone-resistant strains.

Clin Orthop, 2004 Oct, (427), 28 - 36
Eradication by surfactant irrigation of Staphylococcus aureus from infected complex wounds; Huyette DR et al.; Treatment of infected orthopaedic hardware usually requires the removal of the appliance . When the device is removed and immediately replaced, persistent infection frequently complicates this exchange procedure . We modeled the exchange procedure in rats by passing a wire suture through a posterior spinous process and then contaminating the wound with Staphylococcus aureus . We then investigated whether a sequence of surfactant enriched irrigation solutions (Castile soap followed by benzalkonium chloride, sequential surfactant irrigation) had a greater capacity to eradicate Staphylococcus aureus from the experimental wound than did the standard wound irrigant, normal saline . When we left the wire in place through the 2-week course of the study, sequential surfactant irrigation showed only a modest advantage over normal saline (staphylococci recovered from 39% versus 58% of wound cultures respectively) . Simple removal of the wire 24 hours after implantation and bacterial contamination prevented wound infection in most animals (with the wire removed, 38% of the animals remained infected versus 85% with the wire left in place), without regard to the irrigation solution . Alternatively, when we removed the wire after 24 hours, irrigated the wound, and then placed a fresh wire back into the wound, sequential surfactant irrigation showed a significant advantage over NS (54% of the animals irrigated with sequential surfactants remained infected versus 100% of the animals irrigated with normal saline) . Our findings confirm the importance of a contaminated medical device for promoting foreign body infection; our findings also show that sequential surfactant irrigation has therapeutic value in a rat model of orthopaedic device infection; this irrigation protocol should be studied further as a potential agent for the treatment of infected orthopaedic wounds.

Clin Orthop, 2004 Oct, 1(427), 28 - 36
Eradication by Surfactant Irrigation of Staphylococcus aureus from Infected Complex Wounds; Huyette DR et al.; Treatment of infected orthopaedic hardware usually requires the removal of the appliance . When the device is removed and immediately replaced, persistent infection frequently complicates this exchange procedure . We modeled the exchange procedure in rats by passing a wire suture through a posterior spinous process and then contaminating the wound with Staphylococcus aureus . We then investigated whether a sequence of surfactant enriched irrigation solutions (Castile soap followed by benzalkonium chloride, sequential surfactant irrigation) had a greater capacity to eradicate Staphylococcus aureus from the experimental wound than did the standard wound irrigant, normal saline . When we left the wire in place through the 2-week course of the study, sequential surfactant irrigation showed only a modest advantage over normal saline (staphylococci recovered from 39% versus 58% of wound cultures respectively) . Simple removal of the wire 24 hours after implantation and bacterial contamination prevented wound infection in most animals (with the wire removed, 38% of the animals remained infected versus 85% with the wire left in place), without regard to the irrigation solution . Alternatively, when we removed the wire after 24 hours, irrigated the wound, and then placed a fresh wire back into the wound, sequential surfactant irrigation showed a significant advantage over NS (54% of the animals irrigated with sequential surfactants remained infected versus 100% of the animals irrigated with normal saline) . Our findings confirm the importance of a contaminated medical device for promoting foreign body infection; our findings also show that sequential surfactant irrigation has therapeutic value in a rat model of orthopaedic device infection; this irrigation protocol should be studied further as a potential agent for the treatment of infected orthopaedic wounds.

Med Dosw Mikrobiol, 2004, 56(2), 127 - 31
{Determination of methicillin resistance in clinical strains of Staphylococcus aureus in routine microbiological diagnostics}; Slomka M et al.; The aim of this study was to compare the results of two methods: disc-diffusion test and ATB STAPH 5 (version 2000) test applied for determination of methicillin-resistant staphylococci . One hundred and twenty S . aureus strains isolated from clinical specimens in microbiological laboratory of Medical University in Warsaw were investigated . Identification and drug resistance were determined using automatic ATB Expression System . We compared the results of methicillin-resistant S . aureus detection by disc-diffusion method (oxacillin 1 microg) and ATB STAPH 5; version 2000 (bioMerieux sa) . In the case of 116 strains S . aureus identical results were obtained in both methods, 4 strains gave inconsistent results in these two methods . Results that were obtained show that the ATB STAPH 5 (version 2000) test is as useful for routine determination of MRSA and MSSA strains as the disc-diffusion method, and may be used alternatively.

Diagn Microbiol Infect Dis, 2004 Nov, 50(3), 223 - 5
Improvement of a latex agglutination test for the evaluation of oxacillin resistance in coagulase-negative staphylococci; Corso A et al.; The "Slidex MRSA Detection" test (Denka Seiken, Japan) is a latex agglutination assay able to detect PBP2a . We evaluated its ability to differentiate mecA-positive from mecA-negative coagulase-negative staphylococci . We included 100 coagulase-negative staphylococci clinical isolates belonging to 9 species, 54 mecA positive and 46 mecA negative, as characterized by PCR . The specificity achieved using the manufacturer's instructions was 100%, but the sensitivity was only 57% . To increase sensitivity, we introduced modifications into the standard protocol . Using either large inocula or oxacillin induction before test performance, we achieved 100% sensitivity.

Acta Vet Scand, 2004, 45(1-2), 37 - 45
Antimicrobial resistance in Staphylococcus spp., Escherichia coli and Enterococcus spp . in dogs given antibiotics for chronic dermatological disorders, compared with non-treated control dogs; Rantala M et al.; The aim of this study was to evaluate antimicrobial resistance in canine staphylococci, Escherichia coli and enterococci, which were isolated from 22 dogs with pyoderma and a history of previous antibiotic treatment, compared to bacterial isolates from 56 non-treated control dogs . Two isolates of each bacterial species per dog were investigated, if detected . Staphylococcal isolates from dogs with pyoderma (35 isolates) were more resistant to sulphatrimethoprim than the isolates from controls (56 isolates) (57% vs . 25%, p < 0.004) . Multiresistance in staphylococci was also more common in dogs with pyoderma (29% vs . 9%, p = 0.02) . A similar trend among isolates of E . coli was detected (24 and 74 isolates from treated and control dogs, respectively), but the differences were not significant . Resistance for macrolide-lincosamides was approximately 20% among staphylococci in both groups . Resistance to ampicillin among enterococci was 4%-7% . The age of the dogs might have an impact on resistance: multiresistance among staphylococcal isolates from younger dogs (< or = 5 years) was more common than in older dogs (26 years) (24%, vs . 0%, 63 and 27 isolates, respectively, p = 0.02) . Staphylococci in younger dogs were more resistant to tetracycline (48% vs . 11%, p < 0.001) and sulphatrimethoprim (48% vs . 15%, p < 0.01) than those in older dogs . In contrast, the isolates of E . coli from older dogs tended to be more resistant, although a significant difference was detected only in resistance to tetracycline (13% vs . 2% of 40 and 50 isolates respecthely, p = 0.04)) . The results of this small study indicate that resistance in canine staphylococci in the capital area of Finland is comparable with many other countries in Europe . Resistance in indicator bacteria, E . coli and enterococci, was low.

J Antimicrob Chemother, 2004 Dec, 54(6), 1127 - 9 Epub 2004 Nov 05.
Comparison of assays for detection of agents causing membrane damage in Staphylococcus aureus; O'neill AJ et al.; OBJECTIVES: To develop a novel beta-galactosidase leakage assay for Staphylococcus aureus and to evaluate this alongside other simple methods for detection of agents that cause membrane damage in staphylococci . METHODS: Using a PCR-based approach, a derivative of S . aureus RN4220 was constructed carrying the Escherichia coli lacZ gene under the control of the strong staphylococcal promoter, cap1A . Leakage of beta-galactosidase (BG) from this strain was examined after exposure for 10 min to various membrane-damaging agents at 4xMIC, using a fluorescence assay and the substrate 4-methylumbelliferyl-beta-d-galactoside . Other assays for membrane damage involving protoplast lysis (PL), leakage of material absorbing at 260 nm (OD) and ATP release as well as the BacLight (BL) assay were carried out using established methods . RESULTS: All the assays, with the exception of the PL assay, detected membrane damage induced by cetyltrimethylammonium bromide, nisin, clofazimine and protegrin IB-367 . However, the ability to detect membrane damage induced by these agents differed between the assay systems . The assays also varied considerably in their signal-to-noise ratio, with the ATP assay providing values for nisin approaching 100-fold that of the control . CONCLUSIONS: The PL assay is unsuitable for detection of membrane-damaging agents in S . aureus . The other assays, including the BG assay, detect membrane damage . The OD assay should be sufficient for most purposes since it is effective, rapid and cheap to perform . Studies requiring maximum sensitivity and discrimination should employ the ATP assay.

Folia Microbiol (Praha), 2004, 49(4), 353 - 86
Molecular diagnostics of clinically important staphylococci; Stepan J et al.; Bacterial species of the genus Staphylococcus known as important human and animal pathogens are the cause of a number of severe infectious diseases . Apart from the major pathogen Staphylococcus aureus, other species until recently considered to be nonpathogenic may also be involved in serious infections . Rapid and accurate identification of the disease-causing agent is therefore prerequisite for disease control and epidemiological surveillance . Modern methods for identification and typing of bacterial species are based on genome analysis and have many advantages compared to phenotypic methods . The genotypic methods currently used in molecular diagnostics of staphylococcal species, particularly of S . aureus, are reviewed . Attention is also paid to new molecular methods with the highest discriminatory power . Efforts made to achieve interlaboratory reproducibility of diagnostic methods are presented.

J Clin Microbiol, 2004 Nov, 42(11), 5245 - 8
Usefulness of routine epicardial pacing wire culture for early prediction of poststernotomy mediastinitis; Mekontso-Dessap A et al.; Poststernotomy mediastinitis (PSM) is one of the most serious complications of cardiac surgery, and its associated morbidity and mortality demand early recognition for emergency therapy . In this study, we investigated the usefulness of epicardial pacing wire (EPW) cultures for the prediction of PSM . Among 2,200 patients who underwent a cardiac surgical procedure at our hospital between 1 January 1999 and 31 December 2001, 82 (3.7%) had PSM; Staphylococcus aureus was the organism (45.1%) most frequently isolated at the time of surgical debridement . EPWs from 1,607 (73.0%) patients, 73 (4.5%) of whom developed PSM, were cultured . EPW cultures from 466 (29.0%) were positive, most often (74.9%) for coagulase-negative Staphylococci . EPW cultures were truly positive in 26 cases, truly negative in 1,106 cases, falsely positive in 428 cases, and falsely negative in 47 cases (with sterile cultures in 35 cases and a culture positive for an organism different from that isolated at the time of debridement in 12 cases) . EPW culture had a positive predictive value of only 5.7% and a high negative predictive value (95.9%) for the diagnosis of PSM, with an accuracy of 70.4% . However, the likelihood ratio of positive (1.27) and negative (0.89) tests indicated only small changes in pretest-to-posttest probability . Therefore, a strategy of routine culture of EPWs to predict PSM seems questionable.

J Clin Microbiol, 2004 Nov, 42(11), 5041 - 6
Evaluation of the BD PHOENIX automated microbiology system for detection of methicillin resistance in coagulase-negative staphylococci; Horstkotte MA et al.; The new BD PHOENIX automated microbiology system (Becton Dickinson Diagnostic Systems, Sparks, Md.) is designed for automated rapid antimicrobial susceptibility testing and identification of clinically relevant bacteria . In our study, the accuracy and speed of the BD PHOENIX oxacillin MIC determination for detecting methicillin resistance was evaluated for 200 clinical isolates of coagulase-negative staphylococci (CoNS) . Compared to mecA PCR, the BD PHOENIX system detected methicillin resistance with a sensitivity of 99.2% . According to the actual NCCLS oxacillin MIC breakpoint of > or =0.5 microg/ml, the specificity was only 64.9%, attributable to false-positive results in 26 mecA-negative strains, including 16 non-Staphylococcus epidermidis strains . Alternative oxacillin breakpoints of > or =1, > or =2, and > or =4 microg/ml resulted in increased specificities of 83.8, 94.6, and 100% and high sensitivities of 99.2, 99.2, and 96.7%, respectively . Similarly, NCCLS broth microdilution oxacillin MICs exhibited a sensitivity of 100% but a low degree of specificity . However, the previous oxacillin MIC breakpoint of > or =4 microg/ml performed with a sensitivity of 98.4% and a specificity of 98.7% . BD PHOENIX oxacillin MIC results were available after 9 h for 40.5% of the examined CoNS strains and were completed after 17 h . Our results revealed the high reliability of the BD PHOENIX system as a phenotypic method for detection of resistance to oxacillin in mecA-positive CoNS . However, for the improvement of specificity, reevaluation of the optimal oxacillin MIC breakpoint for CoNS appears to be necessary.

J Clin Microbiol, 2004 Nov, 42(11), 4988 - 95
Development and evaluation of a quality-controlled ribosomal sequence database for 16S ribosomal DNA-based identification of Staphylococcus species; Becker K et al.; To establish an improved ribosomal gene sequence database as part of the Ribosomal Differentiation of Microorganisms (RIDOM) project and to overcome the drawbacks of phenotypic identification systems and publicly accessible sequence databases, both strands of the 5' end of the 16S ribosomal DNA (rDNA) of 81 type and reference strains comprising all validly described staphylococcal (sub)species were sequenced . Assuming a normal distribution for pairwise distances of all unique staphylococcal sequences and choosing a reporting criterion of > or =98.7% similarity for a "distinct species," a statistical error probability of 1.0% was calculated . To evaluate this database, a 16S rDNA fragment (corresponding to Escherichia coli positions 54 to 510) of 55 clinical Staphylococcus isolates (including those of the small-colony variant phenotype) were sequenced and analyzed by the RIDOM approach . Of these isolates, 54 (98.2%) had a similarity score above the proposed threshold using RIDOM; 48 (87.3%) of the sequences gave a perfect match, whereas 83.6% were found by searching National Center for Biotechnology Information (NCBI) database entries . In contrast to RIDOM, which showed four ambiguities at the species level (mainly concerning Staphylococcus intermedius versus Staphylococcus delphini), the NCBI database search yielded 18 taxon-related ambiguities and showed numerous matches exhibiting redundant or unspecified entries . Comparing molecular results with those of biochemical procedures, ID 32 Staph (bioMerieux, Marcy I'Etoile, France) and VITEK 2 (bioMerieux) failed to identify 13 (23.6%) and 19 (34.5%) isolates, respectively, due to incorrect identification and/or categorization below acceptable values . In contrast to phenotypic methods and the NCBI database, the novel high-quality RIDOM sequence database provides excellent identification of staphylococci, including rarely isolated species and phenotypic variants.

J Clin Microbiol, 2004 Nov, 42(11), 4947 - 55
New quadriplex PCR assay for detection of methicillin and mupirocin resistance and simultaneous discrimination of Staphylococcus aureus from coagulase-negative staphylococci; Zhang K et al.; Major challenges in diagnostic molecular microbiology are to develop a simple assay to distinguish Staphylococcus aureus from the less virulent but clinically important coagulase-negative staphylococci (CoNS) and to simultaneously determine their antibiotic resistance profiles . Multiplex PCR assays have been developed for the detection of methicillin- and mupirocin-resistant S . aureus and CoNS but not for the simultaneous discrimination of S . aureus from CoNS . We designed a new set of Staphylococcus genus-specific primers and developed a novel quadriplex PCR assay targeting the 16S rRNA (Staphylococcus genus specific), nuc (S . aureus species specific), mecA (a determinant of methicillin resistance), and mupA (a determinant of mupirocin resistance) genes to identify most staphylococci, to discriminate S . aureus from CoNS and other bacteria, and to simultaneously detect methicillin and mupirocin resistance . Validation of the assay with 96 ATCC control strains and 323 previously characterized clinical isolates, including methicillin- and mupirocin-sensitive and -resistant S . aureus and CoNS isolates and other bacteria, demonstrated 100% sensitivity, specificity, and accuracy . This assay represents a simple, rapid, accurate, and reliable approach for the detection of methicillin- and mupirocin-resistant staphylococci and offers the hope of preventing their widespread dissemination through early and reliable detection.

Med Dosw Mikrobiol, 2004, 56(1), 19 - 27
{Coagulase-negative staphylococci in municipal waste}; Sobis-Glinkowska M et al.; The total of 259 coagulase-negative staphylococci isolates gained from aerosols created during dumping and utilisation of municipal waste were investigated . Species and subspecies identification allowed to determine predominance of novobiocin-resistant species which primarily colonise rodents or other animals . However, about 30% of isolates were species originating from humans . Metabolic properties of the studied group of isolates were examined, as well as their sensitivity to a set of 8 commonly used antibiotics: amoxicillin, erythromycin, tetracycline, clindamycin, chloramphenicol, gentamicin, trimethoprim/sulfamethoxazole and ciprofloxacin . Many isolates resistant to erythromycin (19%), tetracycline (13%) and a considerably smaller group resistant to clindamycin (6.2%), chloramphenicol (2%) and trimethoprim/sulfamethoxazole (1%) were found . It appeared that processes of occurring at the time of dumping and utilisation of waste affect the prevalence of only some features . The examined metabolic features were found to be relatively stable and no changes were observed, which would indicate the tendency of adaptation to existence in the inanimate matter environment . Only isolates with active nitrate reductase were more frequently detected . The increase in frequency of occurrence of isolates resistant to tetracycline and chloramphenicol and simultaneous elimination of isolates resistant to other antibiotics were observed.

Med Dosw Mikrobiol, 2004, 56(1), 11 - 7
{Drug resistant coagulase-positive staphylococci strains in food}; Majczyna D et al.; From the 1572 food samples, examined in Microbiology Department of Frozen Food Industry Research Laboratory in Lodz, 79 (5.0%) coagulase-positive staphylococci strains were isolated . All the strains were sensitive to vancomycin, gentamycin and chloramphenicol . Only individual staphylococci strains were resistant to erythromycin (1.3%), lincomycin (2.5%) and ciprofloxacin (2.5%) . 20.3% strains, isolated mainly from raw meat, were resistant to doxycycline and 6.3% to oxacillin . 38.0% of coagulase-positive staphylococci strains had positive results of cefinase test . One strain isolated from minced meat was resistant to methicillin and at the same time it was producing beta-lactamases.

Med Dosw Mikrobiol, 2004, 56(1), 1 - 9
{Molecular analysis of methicillin-resistant staphylococci isolated from hospital patients and in the out-patient clinic}; Malecka-Mikosz O et al.; In this study, a molecular analysis of the methicillin-resistant coagulase-negative staphylococci strains was performed . The obtained results of the biochemical and drug resistant pattern investigations were insufficient to assess the relationship between the strains . Therefore genotyping by the restriction fragment length polymorphism analysis (PCR-RFLP) method was performed . Analyzed strains characterized presence of the mecA gene-PCR products . The PCR products were digested with DraI and TasI, and the fragments separated by agarose gel electrophoresis . Typing of the methicillin-resistant gene using PCR-RFLP showed that all MRCNS strains possess an identical restriction pattern of the mecA gene . This identical restriction pattern of the mecA gene in investigated strains may suggest an easy transfer of this gene between different staphylococci species and lead to the spreading of methicillin-resistant among hospital strains . Furthermore performing the comparison of different phenotype and genotype methods has shown that the PCR-RFLP method is quick and reliable, enabling the detection and estimation of the relationship between MRCNS strains.

FEMS Microbiol Lett, 2004 Nov 15, 240(2), 225 - 8
Rapid detection of Panton-Valentine leukocidin from clinical isolates of Staphylococcus aureus strains by real-time PCR; Deurenberg RH et al.; To allow rapid identification of Panton-Valentine leukocidin (PVL)-producing Staphylococcus aureus strains, a real-time PCR assay for detection of PVL was developed . This assay is convenient, since it can be applied directly on bacterial suspensions and does not require previous DNA purification . Furthermore, the assay was found to be highly reproducible, robust and specific, since positive results were generated exclusively with PVL-positive S . aureus strains, and neither with PVL-negative strains nor staphylococci other than S . aureus.

Rhinology, 2004 Sep, 42(3), 131 - 6
The pathogenicity and antibiotic resistance of coagulase-negative Staphylococci isolated from the maxillary and ethmoid sinuses; Aral M et al.; AIM OF THE STUDY: To investigate the pathogenicity and antibiotic resistance of coagulase-negative staphylococci (CNS) isolated from the maxillary and ethmoid sinuses of patients undergoing endoscopic sinus surgery for chronic sinusitis . PATIENTS AND METHODS: Ninety-three patients (63 males, 30 females) aged between 19 - 68 years, who had undergone functional endoscopic sinus surgery (FESS) for chronic sinusitis, were included in the study . Nasal mucosa, skin and adjacent structures were cleansed with povidone-iodine solution before surgery to prevent a probable contamination . In all patients, nasal swabs were taken before and after the application of povidone-iodine solution . Colonies isolated and identified as Staphylococci in cultures were further investigated for pathogenicity and antibiotic susceptibility . Slime test was used to determine the pathogenicity of CNS . The relationship between antibiotic resistance of pathogenic and non-pathogenic CNS was compared by chi2 analysis . RESULTS: While bacterial growth rate was 62.3% in nasal swab cultures taken before the application of povidone-iodine solution, it decreased to 12.9% after the application of solution . Microorganisms were isolated in 95.6% of cultures taken from maxillary sinuses and in 91.3% of cultures obtained from ethmoid sinuses during the FESS . The most frequently isolated microorganism in each of the sinuses was CNS . Slime test was carried out in 30 CNS isolated . Twelve of these were slime positive and 18 were slime negative . While 83.3% of CNS isolated was resistant to penicilin, all of CNS were sensitive to vancomycin and teikoplanine . The difference between slime positive and slime negative CNS for gentamicin and ciprofloxacin resistance was statistically significant (p<0.05) . CONCLUSION: We consider that the pathogenicity tests like slime production and antimicrobial susceptibilities of CNS frequently isolated from the patients with chronic sinusitis should be investigated and also these microorganisms should be kept in mind in the selection of empiric treatment.

Arch Pediatr, 2004 Nov, 11(11), 1314 - 8
{A routine prospective survey process to detect nosocomial bacterial colonization in a neonatal unit: risk factors for acquisition.}; Campeotto F et al.; A systematic analysis of weekly nasal and rectal swabs was carried out in a neonatal unit in order to detect colonization with multiresistant bacteria (MRB) . PATIENTS AND METHODS: During a 6-month period, rectal and nasal samples were taken in 187 consecutively hospitalized newborns, the day of the admission (day 0) and every week until discharge, in order to detect MRB, mainly methicillin-resistant coagulase negative staphylococci (MRCoNS), Staphylococcus aureus and multi-resistant Gram-negative bacilli . RESULTS: Among 187 infants, 50 were already colonized at entrance and excluded from the study . In others, 49 (35%) were colonized by at least one MRB, with a total of 71 strains isolated . The most frequent was MRCoNS, especially Staphylococcus epidermidis (66.1%) . Gram-negative bacilli accounted for 9.8% . Colonization began earlier with MRCoNS than with Gram-negative bacilli, 7.8 +/- 6 vs . 15.5 +/- 16 days, P=0.004, and finished earlier 22.7 +/- 15 vs . 38.5 +/- 16 days, P=0.03 . Colonized children exhibited by univariate analysis a lower birth weight, more frequent parenteral nutrition or previous hospitalization in a neonatal unit and a younger age at admission . Odds ratio for colonization were 4.06 for prematurity and 43.83 for a previous hospitalization . MRCoNS at days 15 (P <0.05) and 22 (P <0.05) were correlated with the empiric use of antibiotics . No nosocomial infection occurred during the study . CONCLUSION: A high rate of newborns were colonized with MRB in our unit, especially MRCoNS, acquired earlier than Gram-negative bacilli, with a favoring action of empiric antibiotherapy.

Eur J Cancer, 2004 Nov, 40(16), 2452 - 8
Port-A-Cath infections in children with cancer; Hengartner H et al.; Implanted subcutaneous (s.c.) central venous port accesses including Port-A-Cath (PAC) facilitate the administration of chemotherapy or blood products and are frequently used in children with cancer . The incidence of PAC-related infections was determined in 155 consecutive paediatric cancer patients with PAC followed for a total of 134,773 days (median, 738; range, 25-2080) . Overall, 48 bloodstream infections occurred in 26 patients . 12 (25%) of these infections and 3 local infections at the insertion site were treatment-resistant and demanded removal of the PAC . Coagulase-negative staphylococci were involved in 12 of these 15 episodes . The rate of clearly PAC-related infections in this so far largest reported series was 0.11 episodes per 1000 PAC days, one of the lowest in the literature . Although catheter-related infections demanded PAC removal in 8% of our patients, the long periods PAC were in use and their benefits argue for continued PAC use in the paediatric cancer population.

Int J Antimicrob Agents, 2004 Nov, 24(5), 444 - 9
Bactericidal activity of quinupristin-dalfopristin against strains of Staphylococcus aureus with the MLS(B) phenotype of resistance according to the erm gene type; Clarebout G et al.; The bactericidal activity of quinupristin-dalfopristin was assessed by time-kill experiments against Staphylococcus aureus strains with characterized phenotypes and genotypes of MLS(B) resistance . A set of laboratory strains composed of isogenic pairs of S . aureus RN4220 derivatives containing or not the erm(A), erm(B) or erm(C) genes constitutively expressed and of 13 clinical isolates containing these genes inducibly or constitutively expressed were studied . Three of the clinical isolates with erm(B) or erm(A) genes had an unusual inducible MLS(B) cross resistance . The early bactericidal activity of quinupristin-dalfopristin was altered against strains expressing constitutive quinupristin resistance regardless of the erm(A), erm(B) or erm(C) type of gene . We conclude that the bactericidal activity of quinupristin-dalfopristin against staphylococci was dependent on the activity of quinupristin rather than on the erm genotype of the strain.

Antimicrob Agents Chemother, 2004 Nov, 48(11), 4240 - 5
Evolution of the antimicrobial resistance of Staphylococcus spp . in Spain: five nationwide prevalence studies, 1986 to 2002; Cuevas O et al.; Data regarding the evolution of Staphylococcus resistance in a whole country have a definite influence on the design of empirical treatment regimens . Nevertheless, incidence studies over long periods of time are expensive and very difficult to carry out . In order to ascertain the present situation of the antimicrobial resistance of Staphylococcus in Spain and the change of this resistance over time, we performed five point prevalence studies (1986 to 2002) in a large group of Spanish hospitals (from 68 institutions in 1986 to 143 in 2002) collecting all Staphylococcus strains isolated on a single selected day . All microorganisms were identified in the five studies at the same laboratory, and antimicrobial susceptibility testing was performed against 17 antimicrobial agents by the agar dilution method and a microdilution method . During this period, there was an overall increase in resistance to most antimicrobials among Staphylococcus aureus/coagulase-negative staphylococci, mainly to oxacillin (1.5%/32.5% in 1986 versus 31.2%/61.3% in 2002) (P < 0.001), erythromycin (7%/41.1% in 1986 versus 31.7%/63% in 2002) (P < 0.001), gentamicin (5.2%/25.4% in 1986 versus 16.9%/27.8% in 2002) (P < 0.001; P = 0.5), and ciprofloxacin (0.6%/1.1% in 1986 versus 33.9%/44.9% in 2002) (P < 0.001) . All of the isolates were uniformly susceptible to glycopeptides, linezolid, and quinupristin/dalfopristin . Resistance of S . aureus to trimethoprim/sulfamethoxazole was very low (from 0.5% to 2.1%) (P = 0.152) . Periodic performance of prevalence studies is a useful, inexpensive, and easy tool to know the nationwide situation of a microorganism and its resistance to antimicrobials; it also helps us assess the emergence and spread of antimicrobial resistance.

Turk J Pediatr, 2004 Jul-Sep, 46(3), 251 - 5
Pediatric blood culture: time to positivity; Kara A et al.; The aim of this study was to determine how long it takes blood culture to become positive using a blood culture system that can be monitored continuously in pediatric patients . Data were collected prospectively on 1,000 positive blood culture results from a tertiary pediatric university hospital from April 2000 to May 2002 . The laboratory used the BACTEC 9120 fluorescent blood culture system . Patient's age ranged from less than a day to 20 years of age (mean 3 years) . Five hundred and four cultures (50.4%) out of 1,000 yielded coagulase negative staphylococcus (CNS), 81 (8.1%) S . aureus, 53 (5.3%) . Pseudomonas and 50 (5.0%) Klebsiella species . Of the 504 coagulase negative staphylococcal blood culture isolates, 314 (62.3% of CNS) were regarded as skin contaminants . Of the 1,000 cultures, 9.6% were reported as positive in the first day, 27.8% in the second day, 54.7% in the third day, 77.0% in the fourth and 89.4% in the fifth day . There was no association between previous antibiotic usage and the period required for isolate recovery . The clinician can expect to get results of positive blood cultures with susceptibility data, at a rate of 77.1% by day four and almost 90% by day five of sampling in the bacteriemic patient . Blood cultures yielding coagulase negative staphylococci in the first three days almost always show bacteremia with those microorganisms.

Res Microbiol, 2004 Nov, 155(9), 755 - 60
Comparative evaluation of coagulase-negative staphylococci (CoNS) adherence to acrylic by a static method and a parallel-plate flow dynamic method; Cerca N et al.; The main goal of this work was to evaluate the adhesion to acrylic of several clinical strains of Staphylococcus epidermidis and Staphylococcus haemolyticus using both static and dynamic adhesion methods, and to compare the results obtained with these two methods . Adhesion was evaluated using the static slide method with different washing procedures, and the parallel plate flow chamber method . The extent of S . epidermidis adhesion, assessed by both methods, was greater than that of S . haemolyticus . The number of bacteria which adhered using the static method was lower than that using the dynamic method . It was found that the simple static method, when performed with an accurate washing procedure, can be as effective as the dynamic flow method for assessing differences in the adherence capacity of strains . Although the dynamic flow method yielded more overall information, its greater complexity and cost may not always justify its use for certain experimental comparisons . This investigation has shown that simple static adhesion methods, when performed accurately, can be used to evaluate differences in adhesion capacity.

Clin Infect Dis, 2004 Nov 1, 39(9), 1285 - 92 Epub 2004 Oct 11.
A randomized clinical trial to compare fleroxacin-rifampicin with flucloxacillin or vancomycin for the treatment of staphylococcal infection; Schrenzel J et al.; BACKGROUND: Oral combination therapy with fluoroquinolones plus rifampicin is a promising alternative to standard parenteral therapy for staphylococcal infections . METHODS: In a multicenter, randomized trial, we compared the efficacy, safety, and length of hospital stay for patients with staphylococcal infections treated either with an oral combination of a fluoroquinolone (fleroxacin) plus rifampicin or with standard parenteral treatment (flucloxacillin or vancomycin) . Patients were included if cultures showed the presence of bacteremia or deep-seated infections with Staphylococcus aureus (104 patients) or catheter-related bacteremia due to drug-susceptible, coagulase-negative staphylococci (23 patients) . RESULTS: The cure rate in the intention-to-treat analysis was 78% for the fleroxacin-rifampicin group (68 patients) and 75% for the standard therapy group (59 patients; 47 received flucloxacillin, and 12 received vancomycin); in the population of clinically evaluable patients (n=119), the cure rate was 82% and 80%, respectively; and in the population of microbiologically evaluable patients (n=103), the cure rate was 86% and 84%, respectively . Clinical and bacteriological failures after S . aureus infections were documented in similar proportions of patients . The median length of hospital stay after study entry was 12 days in the fleroxacin-rifampicin group, compared with 23 days in the standard treatment group (P=.006) . More adverse events probably related to the study drug were reported in the fleroxacin-rifampicin group than in the standard therapy group (15 of 68 vs . 5 of 59 patients; P=.05) . CONCLUSIONS: This study suggests that an oral regimen containing a fluoroquinolone plus rifampicin may be effective for treating staphylococcal infections, allowing earlier discharge from the hospital.

Ann Hematol, 2005 Jan, 84(1), 40 - 6 Epub 2005 Jan.
Bacterial and fungal bloodstream isolates from 796 hematopoietic stem cell transplant recipients between 1991 and 2000; Ortega M et al.; To examine shifts in the etiology, incidence, evolution, susceptibility, and patient mortality of bacterial and fungal bloodstream isolates (BSIs) from hematopoietic stem cell transplantation (HSCT) recipients, we reviewed the BSIs of 796 patients who underwent an HSCT in our institution during a 10-year period . Four hundred eighty-nine episodes of bacterial and fungal BSI were detected in 330 patients (41%) . Three hundred ten isolates (63%) were gram-positive bacteria, 142 (29%) were gram-negative, and 18 and 19 isolates were different species of anaerobic organism and Candida spp . (both 4%) . Coagulase-negative staphylococci (CoNS), with 210 isolates, were the organism most frequently isolated in each year of study and during the three phases of immune recovery after HSCT . The ratio of gram-positive to gram-negative has declined from 3.3 (1991-1992) to 1.8 (1999-2000) . Crude mortality occurred in 47 cases of 489 BSI episodes (10%) . Mortality according to groups was gram-negative, 7%; gram-positive, 9%; and anaerobic bacteria, 11% . Candida spp . was the group that accounted for the highest crude mortality, with 42% . Gram-positive microorganisms were isolated more often than gram-negative organisms, but the trend is reversing . CoNS were the leading pathogen during the 10 years of study and during the three phases of immune recovery after HSCT . Crude mortality of HSCT patients with BSI was low except for infections caused by Candida spp.

Ann Rheum Dis, 2004 Nov, 63(11), 1450 - 2
The pustular skin lesions in Behcet's syndrome are not sterile; Hatemi G et al.; BACKGROUND: The pustular skin lesions of Behcet's syndrome (BS) are clinically and histopathologically similar to ordinary acne, but BS patients get lesions at sites not commonly involved in acne, such as the legs and arms . The microbiology of these lesions has not been studied adequately . OBJECTIVE: To make a detailed study of the microbiology of BS lesions . METHODS: Subjects were patients with BS and acne vulgaris . Material was extracted from pustular lesions and directly plated to aerobic and anaerobic media by sterile swab . Anaerobic bacteria were identified using a commercial kit (API 20A) . Aerobic bacteria were defined by standard procedures . RESULTS: 58 BS patients and 37 acne patients were studied . Pustules were cultured from the following sites: BS patients (70 pustules): face (17), back (30), chest (2), arm (4), leg (17); acne patients (37 pustules): face (27), back (6), chest (1), arm (2), leg (1) . At least one type of microorganism was grown from each pustule . Staphylococcus aureus (41/70, 58.6%, p = 0.008) and Prevotella spp (17/70, 24.3%, p = 0.002) were significantly more common in pustules from BS patients, and coagulase negative staphylococci (17/37, 45.9%, p = 0.007) in pustules from acne patients . CONCLUSIONS: The pustular lesions of BS are not usually sterile . The microbiology of these lesions is different from ordinary acne . It remains to be determined whether the infection is secondary or has any pathogenic implications.

Am J Vet Res, 2004 Sep, 65(9), 1265 - 8
Methicillin resistance of staphylococci isolated from the skin of dogs with pyoderma; Kania SA et al.; OBJECTIVE: To determine the methicillin-resistant profile of staphylococcal isolates from the skin of dogs with pyoderma . ANIMALS: 90 dogs with pyoderma . PROCEDURE: Staphylococci isolated from dogs with pyoderma were tested for susceptibility to methicillin by use of a standard disk diffusion test with oxacillin disks . The DNA extracted from the isolates was tested for the mecA gene that encodes the penicillin-binding protein 2a (PBP2a) by use of a polymerase chain reaction (PCR) assay . The expression of PBP2a was determined with a commercial latex agglutination assay . Species of staphylococcal isolates were identified by use of morphologic, biochemical, and enzymatic tests . RESULTS: Most of the isolated staphylococci were methicillin-susceptible, coagulase-positive Staphylococcus intermedius isolates . Whereas only 2 of 57 S . intermedius isolates were resistant to methicillin, approximately half of the isolates had the mecA gene and produced PBP2a . Staphylococcus schleiferi was the second most common isolate . Widespread resistance to methicillin was found among S . schleiferi isolates . More coagulase-negative S . schleiferi isolates were identified with mecA gene-mediated resistance to methicillin, compared with coagulase-positive S . schleiferi isolates . CONCLUSIONS AND CLINICAL RELEVANCE: The latex agglutination assay for the detection of PBP2a expression coupled with the PCR assay for the mecA gene may provide new information about emerging antimicrobial resistance among staphylococcal isolates.

Haematologica, 2004 Oct, 89(10), 1232 - 7
Quality control of bacterial contamination in autologous peripheral blood stem cells for transplantation; Larrea L et al.; BACKGROUND AND OBJECTIVES: Microbiological follow-up is part of quality control of peripheral blood stem cell (PBSC) manipulation . DESIGN AND METHODS: We prospectively studied microbiological cultures performed in 865 consecutive untreated autologous PBSC harvests from 348 patients . Our aim was to know the rate of microbiological contamination, the optimum moment to evaluate the sample and the clinical significance of the positive findings . RESULTS: Fifty-nine of the 852 samples (6.9%) yielded a positive culture after PBSC collection (sample 1) and 62 samples also yielded positive results before cryopreservation (7.2%) (sample 2) . At the time of the analysis, a total of 520 aphereses had been infused and the number of positive cultures after thawing (sample 3) and after washing (sample 4; 82 aphereses) was 5.4% and 2.3%, respectively . Most of the positive cultures were due to coagulase-negative staphylococci (48 isolates) . After thawing 15 coagulase-negative staphylococci and 2 enterococci isolates were recovered . Comparison between samples using a marginal homogeneity test showed no differences in the rate of contamination observed at the different sampling points . INTERPRETATION AND CONCLUSIONS: Positive microbiological findings in collected PBSC are not due to contamination within the laboratory . Cryopreservation using DMSO does not eradicate bacteria and manipulation does not seem to affect results . To simplify the procedure it would be possible to eliminate the microbiological controls performed immediately before cryopreservation.

Phytother Res, 2004 Aug, 18(8), 674 - 6
Antimicrobial activity of Mahonia aquifolium crude extract and its major isolated alkaloids; Slobodnikova L et al.; The crude extract of Mahonia aquifolium (Pursh) Nutt . stem bark and its two main protoberberine alkaloids, berberine and jatrorrhizine, were tested for their in vitro antimicrobial activity . Twenty strains of coagulase-negative staphylococci and 20 strains of Propionibacterium acnes isolated from skin lesions of patients with a severe form of acne, and 20 strains of Candida sp . isolated from chronic vulvovaginal candidoses were tested for their susceptibility to crude extract and two isolated alkaloids . The minimum inhibitory concentrations obtained in this study illustrate the varying degrees of antibacterial and antifungal activity of the tested agents . The results indicate a rational basis for the traditional use of Mahonia aquifolium for localized skin and mucosal infection therapy, as well as for the possible development of a preparation for supportive therapy of the diseases mentioned above.

Diagn Microbiol Infect Dis, 2004 Oct, 50(2), 125 - 30
Clinical glycopeptide-intermediate staphylococci tested against arbekacin, daptomycin, and tigecycline; LaPlante KL et al.; We examined the activity of arbekacin, daptomycin, tigecycline, and vancomycin against various Staphylococci isolates with glycopeptide-intermediate (n = 25) and heterogeneous susceptibilities (n = 22) (GISS and hGISS) . The minimum inhibitory concentrations (MIC) of each antimicrobial was evaluated in time-kill experiments by using 4 randomly selected GISS isolates tested at 2 and 4 times their respective MIC . The MIC(90) microg/mL ranges for arbekacin, daptomycin, tigecycline, and vancomycin were 2 (0.25-4), 1 (0.0625-2), 0.5 (0.0625-2), and 8 (4-8), respectively . Time kill at 2 times the MIC demonstrated a mean log(10) colony forming units (CFU)/mL change of -2.98 +/- 0.708, -3.6 +/- 0.509, -2.48 +/- 0.647, and +1.14 +/- 0.1 arbekacin, daptomycin, tigecycline, and vancomycin, respectively . At 4 times the MIC, significant activity for all compounds was noted with a log(10) CFU/mL decrease range from 3.68 to 2.74 +/- 0.66 . Overall, all the antimicrobials tested (with the exception of vancomycin) exhibited significant in vitro activity against GISS . These compounds may offer therapeutic options for the treatment of GISS.

Epidemiol Infect, 2004 Oct, 132(5), 921 - 5
Molecular epidemiology of catheter-related bloodstream infections caused by coagulase-negative staphylococci in haematological patients with neutropenia; Muller-Premru M et al.; Catheter-related bloodstream infection (CRBSI) caused by coagulase-negative staphylococci (CNS) is common in haematological patients with febrile neutropenia . As the clinical signs of CRBSI are usually scarce and it is difficult to differentiate from blood culture contamination, we tried to confirm CRBSI by molecular typing of CNS isolated from paired blood cultures (one from a peripheral vein and another from the central venous catheter hub) . Blood cultures were positive in 59 (36%) out of 163 patients . CNS were isolated in 24 (40%) patients; in 14 from paired blood cultures (28 isolates) and in 10 from a single blood culture . CNS from paired blood cultures were identified as Staphylococcus epidermidis . Antimicrobial susceptibility was determined and bacteria were typed by pulsed-field gel electrophoresis (PFGE) of bacterial genomic DNA . In 13 patients, the antibiotic susceptibility of isolates was identical . The PFGE patterns from paired blood cultures were identical or closely related in 10 patients, thus confirming the presence of CRBSI . In the remaining four patients they were unrelated, and suggested a mixed infection or contamination . Since CNS isolates from three patients had identical PFGE patterns, they were probably nosocomially spread amongst them.

Clin Infect Dis, 2004 Oct 1, 39(7), 1010 - 5 Epub 2004 Sep 10.
Antimicrobial resistance to linezolid; Meka VG et al.; Acquired resistance to linezolid, the first approved oxazolidinone, has been selected in laboratory experiments and has been observed in clinical isolates of gram-positive cocci . This resistance has typically been associated with single-nucleotide changes in varying numbers of copies of the genes encoding 23S ribosomal RNA . In the current environment of increasingly prevalent resistance to standard antibiotics, linezolid is an important drug because of its activity against a number of clinically significant gram-positive cocci, including multidrug-resistant staphylococci and enterococci . Although resistance to linezolid remains uncommon, the development of resistance by clinical isolates should prompt increased attention to susceptibility testing for this agent and should be taken into account in consideration of the therapeutic use of this drug.

J Clin Microbiol, 2004 Oct, 42(10), 4846 - 9
icaA is not a useful diagnostic marker for prosthetic joint infection; Frank KL et al.; A collection of 99 staphylococcal isolates associated with prosthetic joint infection and 23 coagulase-negative staphylococci isolated from noninfected arthroplasty-associated specimens were screened in order to determine whether the presence of icaA could be used to distinguish between pathogens and nonpathogens . All Staphylococcus aureus prosthetic joint infection isolates (n = 55) were icaA positive . A total of 46% (20 out of 44) of coagulase-negative staphylococcal prosthetic joint infection isolates were icaA positive, and 30% (7 out of 23) of arthroplasty-associated non-prosthetic joint infection-associated coagulase-negative staphylococcal isolates were icaA positive (P = 0.23) . Certain coagulase-negative Staphylococcus species appeared more likely to be isolated as either arthroplasty-associated non-prosthetic joint infection-associated isolates (e.g., Staphylococcus warneri and Staphylococcus hominis) or pathogens (e.g., Staphylococcus lugdunensis) . The presence of icaA in a coagulase-negative staphylococcal isolate associated with an arthroplasty is not a useful diagnostic indicator of pathogenicity.

J Antimicrob Chemother, 2004 Nov, 54(5), 889 - 896 Epub 2004 Oct 7.
Phenotypic and genotypic aminoglycoside resistance in blood culture isolates of coagulase-negative staphylococci from a single neonatal intensive care unit, 1989-2000; Klingenberg C et al.; OBJECTIVES: To investigate the prevalence of aminoglycoside resistance and genes encoding aminoglycoside-modifying enzymes (AME) in blood culture isolates of coagulase-negative staphylococci (CoNS) from neonates . Materials and methods: A total of 180 isolates from 148 patients collected in a single neonatal unit over a 12 year period were examined for susceptibility to gentamicin, tobramycin, netilmicin, amikacin and arbekacin by Etest and/or disc diffusion . AME genes were detected by PCR . RESULTS: The overall non-susceptibility rates to gentamicin, tobramycin, netilmicin, amikacin and arbekacin were 66%, 68%, 52%, 38% and 1%, respectively . Gentamicin non-susceptibility rates were 4% and 91% in methicillin-susceptible and -resistant isolates, respectively . aac(6')-Ie-aph(2'')-Ia, aph(3')-IIIa and/or ant(4')-Ia were encountered in 125 (69%), 1 (0.5%) and 30 (16.6%) isolates, respectively . Forty-six (26%) isolates negative for AME genes were susceptible to all aminoglycosides . In contrast, 115 (92%), 91 (73%) and 66 (53%) of aac(6')-Ie-aph(2'')-Ia positive isolates were non-susceptible to gentamicin, netilmicin and amikacin, respectively . Only one isolate showed arbekacin resistance . However, aac(6')-Ie-aph(2'')-Ia positive isolates and isolates with gentamicin MIC >/=128 mg/L displayed a significant reduction in arbekacin inhibition zones . CONCLUSIONS: A high prevalence of aminoglycoside resistance was detected and associated with methicillin resistance . Discrepancies between phenotypic and genetic detection of aminoglycoside resistance were discerned . Gentamicin was the preferred substrate for phenotypic detection of aac(6')-Ie-aph(2'')-Ia . Arbekacin showed favourable antibacterial activity even in aac(6')-Ie-aph(2'')-Ia-positive isolates . We suggest including arbekacin in future clinical trials of empirical treatment of late onset neonatal sepsis.

Antibiot Khimioter, 2004, 49(4), 16 - 20
{Experimental basis for the use of new dosage forms of doxorubicin for correction of its hepatotoxic, prooxidant and immunosuppressory effects}
{Investigation of cell wall components in actinomycin D resistant Staphylococcus aureus}
{No authors listed}

Cell walls in 2 strains of Staphylococcus aureus 209P, i.e . actinomycin D susceptible and resistant ones were comparatively investigated . The resistant cells contained much more wall material per a unit of the biomass weight vs the susceptible strain cells, that conformed to thickening of the resistant cell walls detected by electron microscopy and a sharp increase of their electron density . Investigation of peptidoglycans and teichoic acids did not reveal any significant alterations in the structure of the wall components in the actinomycin D resistant cells . Only some increase of glucosamine in the peptidoglycan fraction of the resistant cells vs the susceptible ones was observed . It was shown that preparations of the resistant cell walls and peptidoglycan isolated from the resistant cells were able to bind somewhat lower quantities of actinomycin D vs the analogous preparations of the susceptible cells . The significant decrease of the antibiotic binding by live cells of the resistant strain probably slightly depended on the structure characteristics of the main wall components . The barrier properties of the walls in resistant staphylococci are most likely defined by the wall thickening and consolidation while adapting to actinomycin D.

J Dairy Sci, 2004 Jun, 87(6), 1719 - 26
Changes in milk composition as affected by subclinical mastitis in goats; Leitner G et al.; The mechanism of the effects of subclinical mastitis (SM) at the glandular level in dairy goats on milk yield and its composition as expressed in curd yield (Yc) was studied . Twenty-five Israeli goats of various crossbreeds were chosen; one udder half was naturally infected with identified coagulase-negative staphylococci, and the contralateral gland was free of bacteria . The milk yield of the infected halves was significantly lower than that of the uninfected ones . Somatic cell count and N-acetyl-beta-D-glucosaminidase activity were significantly higher in the infected halves . The lactose concentration in the infected glands was significantly lower than that in the uninfected ones, casein concentrations did not differ, and the whey protein and albumin concentrations were significantly higher in the infected glands . Plasmin activity was significantly higher in the infected glands, whereas plasminogen activity was undetectable . Concentrations of Ca2+ did not differ, whereas Ca2+ activity was significantly lower in the infected glands . The proteose peptone concentration was 1.5 times as great in the infected glands as in the uninfected ones . The Yc was significantly lower in the infected halves, and clotting time was significantly longer . The mechanisms of the effects of SM on milk yield and Yc in goats and sheep are discussed and compared.

Curr Opin Microbiol, 2004 Oct, 7(5), 477 - 87
Staphylococci in colonization and disease: prospective targets for drugs and vaccines; Gotz F; Pathogenic staphylococci are now regarded in the scientific community as antibiotic resistant 'superbugs' because they have an amazing capacity to acquire resistance traits . Surprisingly, antibiotic development has decelerated . Promising targets for drug development are enzymes involved in the biosynthesis of cell envelope structures such as peptidoglycan, teichoic acids, membrane lipids, or cell wall associated adhesins . Compounds that inactivate or neutralize the most aggressive toxins such as the superantigens and the pore forming toxins have also been considered . In the past decade, global regulatory systems have been studied that contribute to virulence and might be candidates for target development . Targets that are particularly promising include all enzymatic reactions that are unique to bacteria and that are involved in central metabolism, such as methionine-tRNA(fMet) formyltransferase or the peptide deformylase, which have been successfully used for designing new inhibitors . There are also several known antibiotics that have roused new interest especially if they are active against multi-resistant staphylococci . Various cell wall components are promising candidates for active and passive immunization strategies such as capsule, slime, teichoic acids or cell wall bound adhesins . Several new targets for drugs or vaccines will arise from the functional analysis of the staphylococcal genomes that contain many hitherto unknown targets.

J Pak Med Assoc, 2004 Jul, 54(7), 357 - 60
Emerging bacterial resistance patterns in febrile neutropenic patients: experience at a tertiary care hospital in Pakistan; Khan MA et al.; OBJECTIVE: To look at the clinical presentations, spectrum and site of isolation of the organisms, sensitivity patterns of the organisms and the antibiotic prescribing practices for the treatment of febrile neutropenic patients at our hospital . METHODS: The data were collected retrospectively from the records of all neutropenic patients with an absolute neutrophil count (ANC) of less than 500/ml admitted during the period of 3 years from August 1999 to July 2002 at AKUH . RESULTS: Out of the total of 404 patients, 65% had hematological malignancies and around half of them had leukaemia, 86% of the patients presented with fever . A total of 124 bacterial organisms were isolated from 96 patients among which 47% were gram positive and 53% were gram negative organisms; 16.1% of the patients had septicaemia . Coagulase Negative Staphylococci (CoNS) were the most common gram positive and E . coli was the most commonly isolated gram negative organism . Most of the gram positive organisms were isolated from blood (67%) . There was emerging resistance to all commonly used antibiotics including imipenem, cloxacillin, vancomycin and amikacin . The average duration of neutropenia was 6.4 days . The mortality rate was 6% . CONCLUSION: There is increasing trend of gram negative organisms developing resistance to commonly used antibiotics . Gram positive bacteria including Enterococcus spp . and CoNS are also showing emerging resistance to vancomycin.

Antimicrob Agents Chemother, 2004 Oct, 48(10), 4037 - 9
Antistaphylococcal activity of CB-181963 (CAB-175), an experimental parenteral cephalosporin; Hoellman DB et al.; Among 265 methicillin-susceptible and -resistant staphylococci, CB-181963 (CAB-175) had a 50% minimum inhibitory concentration of 2 microg/ml and a 90% minimum inhibitory concentration of 4 microg/ml . All strains except two vancomycin-resistant S . aureus and 5 vancomycin-intermediate S . aureus strains were also susceptible to vancomycin and teicoplanin, and all were susceptible to linezolid, ranbezolid, tigecycline, and quinupristin-dalfopristin . Most methicillin-resistant strains were levofloxacin resistant . CB-181963 was bactericidal against all six methicillin-resistant strains at four times the MIC after 24 h.

Antimicrob Agents Chemother, 2004 Oct, 48(10), 4033 - 6
Antistaphylococcal activity of LBM415, a new peptide deformylase inhibitor, compared with those of other agents; Credito K et al.; The MICs of LBM415, a new peptide diformylase inhibitor, were </=0.06 to 4.0 microg/ml for 258 isolates of Staphylococcus aureus and coagulase-negative staphylococci . LBM415 MICs were similar irrespective of whether the strains were methicillin susceptible or resistant . All strains were also susceptible to vancomycin, linezolid, ranbezolid, daptomycin, oritavancin, and quinupristin-dalfopristin . LBM415 at the MIC was bacteriostatic after 24 h.

Adv Perit Dial, 2004, 20, 67 - 70
Emergence of resistance in staphylococci after long-term mupirocin application in patients on continuous ambulatory peritoneal dialysis; Cavdar C et al.; In the present study, we evaluated the effects of once-weekly mupirocin application to catheter exit sites on Staphylococcus aureus and coagulase-negative staphylococcus (CNS) colonization and investigated the resistance of those bacteria to methicillin (MeR) and mupirocin (MuR) . We enrolled 36 continuous ambulatory peritoneal dialysis (CAPD) patients (mean age: 55.1 +/- 1.4 years) into the study . The patients (men/women: 21/15) had been applying mupirocin to the catheter exit site once weekly before the start of the study (mupirocin treatment duration: 3.1 +/- 2.0 years) . During the study period, swabs were taken monthly from the nares, axillae, inguinal area, and catheter exit site . The swabs were inoculated on blood plates . Methicillin and mupirocin susceptibility were tested by disc diffusion according to the interpretative criteria of the National Committee for Clinical Laboratory Standards . We evaluated a total of 144 cultures . Among CNS isolates, the MuR was 66%, and the MeR was 38.8% . At the start of the study period, 3 patients were S . aureus nasal carriers . In nasal swabs, no MeR S . aureus was identified, and only 1 MuR S . aureus was found . Once-weekly application of mupirocin at the exit site in CAPD patients led to comparable rates of colonization by MuR S . aureus as did thrice-weekly or more frequent application . Clinical results showing high mupirocin and methicillin resistance in CNS are controversial.

Ned Tijdschr Geneeskd, 2004 Aug 7, 148(32), 1577 - 81
{Linezolid, an agent from a new class of antibiotics}; Kuijper EJ et al.; Linezolid is the first of a new class of antibacterial agents, the oxazolidinones, to become available . Linezolid has a unique mechanism of action in its inhibition of bacterial protein synthesis in Gram-positive and a number of anaerobic bacteria . Because of this unique mechanism of action, linezolid exhibits no cross-resistance with other antibiotics and is effective against methicillin-resistant staphylococci, penicillin-resistant pneumococci and vancomycin-resistant enterococci . The excellent bioavailability after oral administration (almost 100%) makes it suitable for outpatient treatment and treatment by general practitioners . In the Netherlands, however, the indications for linezolid are limited by its high cost, the availability of other effective antibiotics for the treatment of sensitive micro-organisms, and the toxicity associated with a prolonged treatment period . Resistance to the new agent was reported rather quickly after the introduction of linezolid.

Can J Microbiol, 2004 Jul, 50(7), 493 - 8
PCR-based identification of Staphylococcus epidermidis targeting gseA encoding the glutamic-acid-specific protease; Ikeda Y et al.; The frequency of the gseA gene encoding a glutamic acid-specific serine protease, GluSE, of Staphylococcus epidermidis was investigated . DNA hybridization analysis demonstrated that gseA existed exclusively in S . epidermidis but not in other bacteria examined . A single step PCR assay with a set of designed primers yielded amplification of gseA from all 69 clinical isolates of S . epidermidis taken from patients and healthy adults, whereas production of GluSE was observed in 74% (51/69) of the isolates . Furthermore, none of the 46 clinical isolates of other species of coagulase-negative staphylococci and 45 clinical isolates of Staphylococcus aureus showed amplification, except a Staphylococcus capitis strain . However, this strain was positive for a S . epidermidis-specific DNA region and the DNA sequence of the 16S rRNA gene showed 99% identity with that of S . epidermidis . Therefore, these results indicated that the present PCR assay for gseA was ubiquitous and highly specific for detection of S . epidermidis.

Vet Microbiol, 2004 Oct 5, 103(1-2), 91 - 7
Methicillin-resistant staphylococci isolated from animals; van Duijkeren E et al.; Staphylococci isolated from animals (n=311) were screened for methicillin resistance by oxacillin agar screening . Oxacillin-resistant strains were tested for the presence of the mecA gene by PCR . Isolates were identified by standard techniques and 16S rDNA analysis, and their antimicrobial susceptibilities were tested using an agar diffusion method . MecA-positive strains were further analyzed using pulsed-field gel electrophoresis (PFGE) . From 11 multidrug-resistant staphylococci, 6 were mecA-positive: 2 methicillin-resistant Staphylococcus aureus (MRSA) and 4 Staphylococcus haemolyticus . Screening of 300 staphylococci (100 S . aureus, 100 S . intermedius and 100 coagulase-negative staphylococci (CNS)) randomly chosen from the strain collection of the Veterinary Microbiological Diagnostic Center yielded five oxacillin-resistant coagulase-negative staphylococci, four of which were mecA-positive . PFGE showed that all mecA-positive staphylococci isolated from animals had distinct patterns . However, one MRSA isolated from a flank fistula of a dog showed homology to a human epidemic MRSA cluster, suggesting that transfer of MRSA between humans and dogs might occur.

Diagn Microbiol Infect Dis, 2004 Sep, 50(1), 59 - 69
Occurrence and antimicrobial resistance pattern comparisons among bloodstream infection isolates from the SENTRY Antimicrobial Surveillance Program (1997-2002); Biedenbach DJ et al.; The empiric treatment of patients with bloodstream infections (BSI) has become more complicated in an era of increasing antimicrobial resistance . The SENTRY Antimicrobial Surveillance Program has monitored BSI from patients in medical centers worldwide since 1997 . During 1997-2002, a total of 81,213 BSI pathogens from North America, Latin America, and Europe were tested for antimicrobial susceptibility . S . aureus, E . coli, and coagulase-negative staphylococci were the three most common BSI pathogens in all three regions each year . Prevalence variability was noted in regions for some species, including higher rates of isolation of E . coli in Europe, Enterococcus spp . in North America, and Gram-negative enteric and nonenteric species in Latin America . Patient age analysis showed the most common BSI pathogen among neonates was coagulase-negative staphylococci and among elderly patients, E . coli . Resistance among BSI pathogens was much more prevalent in nosocomial infections and in patients in intensive care units (ICUs); age differences were also noted . Geographically, oxacillin-resistant S . aureus (39.1%, 2002) and vancomycin-resistant enterococci (17.7%, 2002) were highest in North America, and extended-spectrum beta-lactamase-producing Klebsiella spp . (35.8-46.7%) and multidrug-resistant P . aeruginosa (18.7%, 2002) were highest in Latin America . Activity of commonly used antimicrobial agents remained relatively stable in North America, except in the case of vancomycin-resistant enterococci (20% decline between 1997 and 2002) . An epidemiologic investigation of oxacillin-resistant S . aureus in North America identified 10 significant clones (ribotypes) and the common resistance patterns associated with them . Surveillance of BSI pathogens is needed to determine trends of resistance and provide useful information regarding patient risk factors and geographic differences.

Wien Klin Wochenschr, 2004 Jul 31, 116(14), 489 - 94
Effect of hospitalization and antimicrobial therapy on antimicrobial resistance of colonizing Staphylococcus epidermidis; Knauer A et al.; Endogenous infections with multi-resistant S . epidermidis are among the leading causes of nosocomial infections . The effect of hospitalization and antimicrobial therapy on antimicrobial resistance of colonizing staphylococci was determined from swabs of the nose, hand, axilla and groin from 157 patients on one day . Hospitalization for >72 hours, compared with <72 hours, was associated with a higher percentage of isolates resistant to oxacillin (56% versus 19%), gentamicin (40% versus 15%), trimethoprim (36% versus 17%), clindamycin (56% versus 17%), and fusidic acid (20% versus 4%; p < 0.01 for all), but not to rifampicin (6% versus 1%) or fosfomycin (43% versus 34%, p > 0.05 for both) . Concurrent antimicrobial therapy resulted in increased resistance to oxacillin (61% versus 28%), gentamicin (43% versus 20%), and clindamycin (60% versus 26%; p < 0.01 for all), but not to trimethoprim (39% versus 23%), fusidic acid (19% versus 9%), rifampicin (6% versus 3%), or fosfomycin (46% versus 38%, p > 0.05 for all) . The increase in resistant isolates was not independent, since hospitalization and antimicrobial therapy were correlated (p < 0.001) . After adjustment for potential risk factors such as diabetes mellitus, central venous catheters, and hemodialysis, the odds ratio for oxacillin resistance was 2.8-3.6 . None of the risk factors showed statistically significant results, except for the presence of neoplastic disease, which had a significant interaction (P=0.035) . The within-subgroup odds ratios for patients with and without neoplasm were 4.2 (95% CI, 2.3-5.7) and 2.1 (95% CI, 0.78-3.12), respectively . These results show that hospitalization for more than three days, with or without antimicrobial therapy, and the presence of neoplastic disease are associated with increased antimicrobial resistance in colonizing S . epidermidis.

Clin Microbiol Infect, 2004 Oct, 10(10), 939 - 42
Use of sodA sequencing for the identification of clinical isolates of coagulase-negative staphylococci; Sivadon V et al.; This study evaluated the possible advantages provided by a genotypic method over commercially available biochemical systems for the identification of clinical isolates of coagulase-negative staphylococci (CNS) . Partial sequencing of the sodA gene was performed for 168 coagulase-negative clinical isolates of staphylococci identified previously with the ID32 STAPH system . Of these, 101 (60.1%) were identified to the species level with ID32 STAPH, while 67 (39.9%) were misidentified or not identified with certainty . Sequencing of sodA proved useful for resolving all ambiguities or inconclusive identifications generated by the commercially available biochemical identification system.

Scand J Infect Dis, 2004, 36(9), 674 - 9
Pacemaker endocarditis during 18 years in Göteborg; Rundstrom H et al.; Pacemaker endocarditis is a rare but serious complication . Few studies addressing its treatment have been published . Clinical characteristics and outcome were retrospectively studied in 38 patients with 44 episodes of pacemaker infective endocarditis (PMIE) in Goteborg, during 1984-2001 . The male/female ratio of episodes was 27/17 and the mean age 69 y . Transthoracic echocardiography (TTE) showed vegetation in 4/22 (18%) episodes and transoesophageal echocardiography (TEE) in 22/33 (67%) . Staphylococci were isolated in 66% of blood cultures . The pacemaker system (PS) was removed in 28 episodes and in 18 of these there were no signs of reinfection at follow-up . In 16 episodes the PS was not removed, and in 13 of these, signs of infection were found at follow-up . Thus, the present study of PMIE showed staphylococci to be predominant causative agents and demonstrated a high diagnostic sensitivity of TEE . According to our results, PM removal rather than conservative treatment should be considered in all cases.

Clin Microbiol Infect, 2004 Sep, 10(9), 838 - 42
A European perspective on intravascular catheter-related infections: report on the microbiology workload, aetiology and antimicrobial susceptibility (ESGNI-005 Study); Bouza E et al.; The laboratory workload, microbiological techniques and aetiology of catheter-related infections in European hospitals are mostly unknown . The present study (ESGNI-005) comprised a 1-day (22 October 2001), laboratory-based, point-prevalence survey based on a questionnaire completed by microbiology laboratories in European (European Union (EU) and non-EU) hospitals . Also included were questions requesting retrospective information for the year 2000 . In total, 151 hospitals from 26 European countries participated, of which 78.1% were teaching institutions . Overall, the estimated population served by these institutions was 121,363,800, and the estimated number of admissions during 2000 was 6,712,050 . The total number of catheter tips processed during 2000 was 142,727, or 21/1,000 admissions, of which 23.7% were considered to be positive in the institutions using semiquantitative or quantitative techniques . Overall, EU centres received significantly more catheter tip samples/1,000 admissions and had a significantly higher rate of 'positivity' (p < 0.0001) than non-EU centres . Of the institutions surveyed, 11.4% (7.2% in EU countries and 23.7% in non-EU countries; p 0.04) used only qualitative techniques for catheter tip sample processing . On the day of the study, 167 microorganisms were recovered from significant catheter tip cultures (122 patients), of which Gram-positive bacteria represented 70.7%, Gram-negative bacteria 22.2%, and yeasts 7.2% . The five most common microorganisms were coagulase-negative staphylococci, Staphylococcus aureus, Candida spp., Enterococcus spp . and Pseudomonas spp . Overall, 19% of catheter tip cultures were polymicrobial . In the case of S . aureus, 40% of isolates were resistant to oxacillin, as were 63.4% of coagulase-negative staphylococcus isolates . Of 37 Gram-negative isolates, 35% were resistant to cefotaxime, 31% to ceftazidime, and 27% to ciprofloxacin . Imipenem and cefepime had the lowest reported rates of resistance (11%).

J Dairy Res, 2004 Aug, 71(3), 311 - 5
Effect of subclinical intramammary infection on somatic cell counts, NAGase activity and gross composition of goats' milk; Leitner G et al.; The study was aimed at identifying the pathogens causing subclinical udder infections in representative Israeli dairy goat herds and determining their effect on milk quality . Five hundred goats in ten flocks of various breeds and crossbreeds were surveyed . Of the 500 goats, 13.4% were in their first lactation, 36.4% were in their second lactation and 50.2% were in their third or higher lactation . Percentages of udder halves with subclinical intramammary infection in the flocks ranged from 35 to 71% . The effect of the bacteriological infection on somatic cells count (SCC) was significant (P<0.001) . Various species of coagulase-negative staphylococci (CNS), mainly Staphylococcus caprae and Staphylococcus epidermidis, were the main pathogens in infected udder halves . Lactation number did not significantly influence either infection rate of udder halves or SCC, although the percentage of udder halves with no bacteriological findings was higher at the first lactation than at the third lactation . Milk composition (fat, protein and lactose) varied among flocks, with lower mean total protein in uninfected halves than in infected ones and higher lactose in uninfected than infected halves.

J Coll Physicians Surg Pak, 2004 Sep, 14(9), 549 - 52
Central venous catheter-related bloodstream infections in cancer patients; Butt T et al.; OBJECTIVE: To determine the frequency of central venous catheter-related bloodstream infections (CR-BSI) in cancer patients and the antimicrobial susceptibility pattern of the isolates . DESIGN: A cross-sectional study . PLACE AND DURATION OF STUDY: The study was conducted between April 2002 and March 2003 at the Armed Forces Institute of Pathology, Rawalpindi in collaboration with Oncology Units of Armed Forces Bone Marrow Transplant Centre and Combined Military Hospital, Rawalpindi . SUBJECTS AND METHODS: Cancer patients requiring short or long-term central venous catheterization at the time of admission or thereafter were included . Catheter tips on removal were cultured quantitatively; specimens of blood and pus were cultured qualitatively . Isolates were identified and antimicrobial susceptibility testing was performed by standard techniques . RESULTS: Eighty-nine patients were included in the study . The frequency of CR-BSI was 17% . Out of the 19 organisms isolated, 10 (53%) were Gram-positive cocci, 8 (42%) were Gram-negative rods and 1 (5%) was a fungus . Coagulase negative staphylococci (27%) were the predominant pathogens . Among the staphylococci, 46% of the isolates were methicillin-resistant . All Gram-positive isolates were susceptible to glycopeptides . Gram-negative rods were resistant to most of the commonly used antimicrobial groups . CONCLUSION: Central venous catheter is an important source of bloodstream infections in cancer patients . Most of the infections are caused by Gram-positive cocci . Rigorous infection control measures and continuous surveillance are required to curb the frequency of these infections.

Curr Opin Pharmacol, 2004 Oct, 4(5), 471 - 8
Glycopeptides in clinical development: pharmacological profile and clinical perspectives; Van Bambeke F; Vancomycin and teicoplanin are the two glycopeptides currently used in the clinics for the treatment of multiresistant infections by Gram-positive organisms . The development of resistance in enterococci and staphylococci has stimulated the search for new derivatives with improved activity, particularly against strains resistant to conventional derivatives . Three of these, obtained by hemi-synthesis starting from natural compounds, are now in clinical development (oritavancin and telavancin, as derivatives of vancomycin; and dalbavancin, as a derivative of teicoplanin) . The presence of a lipophilic tail on these molecules results in them having a prolonged half-life . It also modifies their mode of action, conferring to them a concentration-dependent bactericidal activity . Their spectrum of activity includes methicillin-susceptible or methicillin-resistant staphylococci, penicillin-resistant pneumococci and enterococci (including vancomycin-resistant strains for oritavancin and telavancin) . Ongoing clinical studies are evaluating the efficacy and safety of these molecules for the treatment of complicated skin and soft tissue infections and bactereamia, in a once-daily (oritavancin, telavancin) or once-weekly (dalbavancin) scheme of administration . Despite these remarkable properties, the use of these potent molecules should be restricted to severe infections by multiresistant organisms to limit the risk of selection of resistance.

J Mater Sci Mater Med, 2001 Dec, 12(10/12), 979 - 82
Binding of vitronectin and clusterin by coagulase-negative staphylococci interfering with complement function; Li DQ et al.; Coagulase-negative staphylococci (CoNS) are commonly associated with infections of prosthetic devices mediated by adsorbed host factors on biomaterial surfaces . Complement activation is known to occur and induce unspecific inflammation around the biomaterials . Human vitronectin (Vn) and clusterin (Clu), two potent inhibitors of complement, can be bound by CoNS . With a hypothesis whether binding of Vn or Clu influences complement activation, two measurements were determined . For Vn, complement activation was measured with a mouse anti-activated human C9 antibody . In the presence of Vn-binding strain, Staphylococcus hemolyticus SM13I, complement activation on a surface pre-coated with Vn occurred as it did in the absence of Vn pre-coating . For S . epidermidis 3380, which does not express binding of Vn, complement activation on a Vn-presented surface was significantly decreased . For Clu, erythrocytes lysis was measured to reflect the end product of complement activation (membrane attack complex) . The complement-induced hemolysis increased when human serum was pre-incubated with Clu-binding strains, S . epidermidis J9P . The enhancement of hemolysis by J9P decreased when serum was supplemented by exogenous Clu . The data imply that interaction between CoNS and Vn or Clu interferes with one of their physiological functions, complement inhibition.

J Antimicrob Chemother, 2004 Oct, 54(4), 818 - 20 Epub 2004 Sep 03.
Reversion to susceptibility in a linezolid-resistant clinical isolate of Staphylococcus aureus; Meka VG et al.; OBJECTIVES: Linezolid resistance in rare isolates of Staphylococcus aureus has been associated with G2576T mutations in domain V of the 23S rRNA gene . We report the analysis of a clinical S . aureus isolate that developed linezolid resistance (MIC of linezolid of 12 mg/L) after a 25 day course of the drug . Sequencing identified G2576T mutations in four of the five copies of the 23S rRNA gene . METHODS: To examine the stability of this resistance, we serially passaged this original isolate 60 times over a 75 day period on antimicrobial-free medium . RESULTS: After 30 passages, the MIC of linezolid had decreased to 8 mg/L and only two of the five copies of the 23S rRNA gene contained the G2576T mutation . After 60 passages, the MIC of linezolid fell to 2 mg/L and only one of the five 23S rRNA gene copies contained the mutation . The original and two passaged staphylococci were indistinguishable by pulsed-field gel electrophoresis . CONCLUSIONS: In the absence of antibiotic pressure, linezolid resistance was unstable in a clinical isolate that did not have all copies of the 23S rRNA gene mutated, although a single copy of mutant rDNA was maintained . Gene conversion was probably the mechanism for this reversion, using the wild-type 23S rRNA gene sequences to replace the G2576T mutation by homologous recombination.

Zh Mikrobiol Epidemiol Immunobiol, 2004 May-Jun, (3), 7 - 10
{Biological properties of microorganisms as the basis for the prognosis of the severity of pyoinflammatory pleuropulmonary diseases}; Abramzon OM et al.; In the study of 65 microbial cultures isolated from the purulent foci in acute pulmonary abscess and acute pyothorax of 48 patients, a wide spectrum of microflora was detected . Staphylococci and Pseudomonas prevailed among aerobes, bacteroids and peptostreptococci--among anaerobes . In cases of the prolonged course of the pathological process, as compared with the common one, microorganisms exhibited hemolytic activity and high antilysozyme and anticomplementary levels . These findings served as the basis for working out a mathematical model for the prognosis of the disease course with 95% probability.

Surg Neurol, 2004 Sep, 62(3), 195 - 9; discussion 199-200
Cytological and bacteriological studies of intraoperative autologous blood in neurosurgery; Kudo H et al.; BACKGROUND: To ensure the safety of salvaged blood in neurologic surgery, reinfused blood through the Cell Saver System (CSS) (Hemonetics) was investigated cytologically and bacteriologically . METHODS: Specimens of reinfused blood were cytologically examined with Papanicolaou or Giemsa stains . Reinfused blood and air in the operating theater were investigated by microbiologic techniques . The concentration of dust particles in the theater was determined . RESULTS: Tumor cells were positive in reinfused blood in 5 of 9 specimens with glioblastoma, in 2 of 8 with pituitary adenoma, and 1 of 13 with meningioma . The probability of migration of meningioma cells into reinfused blood was significantly low in comparison with that of glioma cells . Of the 30 specimens studied microbiologically, the bacterial growth was detected in salvaged blood of 14 specimens (46.7%) and in the air of the operating theater for 8 specimens (26.7%) . In craniotomy, the contamination rate was 10 of 26 specimens of reinfused blood (38.5%) . Most microorganisms were found to be staphylococci . No statistically significant correlation could be found between salvaged blood and air as to contamination or between reinfused blood and the concentration of dust particles in the theater as to bacteriologic results . No infectious complications were found after the operation, though salvaged blood through the CSS was reinfused in 37 patients without glioblastoma or transsphenoidal approach . CONCLUSIONS: The CSS cannot always entrap tumor cells . Salvaged blood should not be reinfused in the patients with glioblastoma or transsphenoidal surgery . None of the patients with reinfusion had any infectious complications . Reinfusion of salvaged blood seems to be safe in neurosurgery.

J Chemother, 2004 Aug, 16(4), 357 - 61
Immunomodulating activity of rifampicin; Ziglam HM et al.; It has been shown that some antibiotics can modify cytokine production . We have examined the effect of rifampicin on secretion of interleukin-1beta (IL-1beta), IL-6, IL-10, and tumor necrosis factor alpha (TNF-alpha) by lipopolysaccharide (LPS)-stimulated or heat killed staphylococci (Pansorbin) stimulated monocytes . Secretion of IL-1beta and TNF-a were significantly inhibited (P<0.002) whereas secretion of IL-6 and IL-10 were significantly increased (P<0.003) by rifampicin treated mononuclear cells . Rifampicin had immunomodulatory effects through its capacity to alter the secretion of tested cytokines by human monocytes.

J Chemother, 2004 Aug, 16(4), 323 - 8
Activity of mupirocin and 14 additional antibiotics against staphylococci isolated from Latin American hospitals: report from the SENTRY antimicrobial surveillance program; Gales AC et al.; A total of 1,346 Staphylococcus aureus (SA) and 498 coagulase-negative staphylococcal (CoNS) strains isolated from 11 Latin American medical centers between 2000 and 2001 were tested against mupirocin and other antimicrobial agents by reference broth microdilution method as part of the SENTRY Antimicrobial Surveillance Program . Oxacillin resistance (OR) was detected in 38.6% of S . aureus and in 78.1% of CoNS . The overall resistance rate to mupirocin was low among S . aureus (3.1%; MIC > or =8 microd/ml) but significantly higher among ORSA compared to oxacillin-susceptible SA (5.4% versus 1.7%; p <0.001) . Mupirocin-resistant S . aureus strains were detected in 9 of 11 centers, with individual center rates varying between 1.8 and 15.7% . Mupirocin resistance rates were high among CoNS (27.5%) and varied widely (10.0 to 48.9%) among the monitored Latin American medical centers . Mupirocin resistance rates appear to be increasing and routine monitoring for potential resistance seems prudent.

J Food Prot, 2004 Aug, 67(8), 1709 - 18
Effects of high-pressure processing on the safety, quality, and shelf life of ready-to-eat meats; Hayman MM et al.; Ready-to-eat (RTE) meats (low-fat pastrami, Strassburg beef, export sausage, and Cajun beef) were pressure treated at 600 MPa, 20 degrees C, for 180 s to evaluate the feasibility of using high-pressure processing (HPP) for the safe shelf-life extension of these products . After processing, samples were stored at 4 degrees C for 98 days during which time microbiological enumeration and enrichments were performed . Additionally, sensory analyses were undertaken to determine consumer acceptability and purchase intent over the duration of storage . Counts of aerobic and anaerobic mesophiles, lactic acid bacteria, Listeria spp., staphylococci, Brochothrix thermosphacta, coliforms, and yeasts and molds revealed that there were undetectable or low levels for all types of microorganisms throughout storage . Comparison of consumer hedonic ratings for unprocessed and processed meats revealed no difference in consumer acceptability, and no deterioration in the sensory quality was evident for any of the products tested during the study . Additionally, inoculated pack studies were conducted to determine if HPP could be used as a postlethality treatment to reduce or eliminate Listeria monocytogenes and thus assess the potential use of HPP in a hazard analysis critical control point plan for production of RTE meats . Inoculated samples (initial level of 10(4) CFU/g) were pressure treated (600 MPa, 20 degrees C, for 180 s) and stored at 4 degrees C, and survival of L . monocytogenes was monitored for 91 days . L . monocytogenes was not detected by plating methods until day 91, but selective enrichments showed sporadic recovery in three of the four products examined . The results show that HPP at 600 MPa, 20 degrees C, for 180 s can extend the refrigerated shelf life of RTE meats and reduce L . monocytogenes numbers by more than 4 log CFU/g in inoculated product.

Vojnosanit Pregl, 2004 May-Jun, 61(3), 255 - 8
{Frequency and colonization rate of intravascular catheters}; Tomanovic B et al.; Clinical signs are not sufficiently reliable for establishing diagnosis of intravascular catheter-related infection . Therefore, microbiological confirmation, based on the culture of the catheter tip after its removal, is necessary in diagnosing the infection . The aim of this study was to determine the frequency and the degree of microbial colonization of intravascular catheters (IVK), and the risk for the onset of sepsis, by using qualitative, semiquantitative (roll plate) and quantitative (vortexing) catheter culture techniques . During the period April 2001-December 2002, 289 intravascular catheters were cultured . A total of 284 microorganisms were isolated from 217 (75%) culture-positive catheters . The frequency of isolation of some organisms was the following: coagulase-negative staphylococci (CNS) 41%, Staphylococcus aureus 19%, Enterococci spp 6%, other gram-positive microorganisms 9%, gram-negative microorganisms 21%, and fungi 4% . In 35 catheters, cultures were polymicrobial; two microorganisms were found in 25 cultures and three were found to be in 10 cultures . There were 122 (46%) intravascular catheters, which were found significantly colonized . A high rate of positivity and a high rate of S . aureus isolates and gram-negative bacteria indicate the need of establishing the exact microbiological diagnosis of these infections, and the rigorous undertaking of adequate control and preventive measures.

Antimicrob Agents Chemother, 2004 Sep, 48(9), 3338 - 42
In vitro activity of the new quinolone WCK 771 against staphylococci; Jacobs MR et al.; The activity of WCK 771, an experimental quinolone developed to overcome quinolone resistance in staphylococci and other bacteria, was determined against quinolone-susceptible and -resistant Staphylococcus aureus and S . epidermidis . WCK 771 MICs for 50 and 90% of the strains tested (MIC(50) and MIC(90), respectively) were 0.008 and 0.015 microg/ml for S . aureus (n = 43) and 0.015 and 0.03 microg/ml for S . epidermidis (n = 44) for quinolone-susceptible isolates, compared to ciprofloxacin values of 0.12 and 0.25 microg/ml and 0.25 and 0.5 microg/ml, respectively . Values for levofloxacin were 0.12 and 0.25 microg/ml and 0.12 and 0.25 microg/ml, those for clinafloxacin were 0.015 and 0.03 microg/ml and 0.015 and 0.03 microg/ml, those for moxifloxacin were 0.03 and 0.06 microg/ml and 0.06 and 0.12 microg/ml, and those for gatifloxacin were 0.06 and 0.12 microg/ml and 0.12 and 0.25 microg/ml, respectively . The WCK 771 MIC(50) and MIC(90), respectively, were 0.5 and 1 microg/ml for both species of staphylococci (n = 73 for S . aureus, n = 70 for S . epidermidis) for isolates highly resistant to ciprofloxacin (MIC(50) and MIC(90), >32 and >32 microg/ml, respectively) . Values for levofloxacin were 8 and 32 microg/ml and 8 and 32 microg/ml, those for clinafloxacin were 1 and 2 microg/ml and 0.5 and 2 microg/ml, those for moxifloxacin 4 and >4 microg/ml and 4 and >4 microg/ml, and those for gatifloxacin were 4 and >4 microg/ml and 2 and >4 microg/ml, respectively . WCK 771 and clinafloxacin demonstrated MICs of 1 microg/ml against three vancomycin-intermediate strains . WCK 771 showed concentration-independent killing for up to 24 h at 2, 4, and 8 times the MICs against quinolone-resistant staphylococci and was also bactericidal after 8 h for high-density inocula (10(8) CFU/ml) of quinolone-resistant strains at 5 microg/ml, whereas moxifloxacin at 7.5 microg/ml was bacteriostatic . WCK 771 was not a substrate of the NorA efflux pump as evident from the similar MICs against both an efflux-positive and an efflux-negative strain . Overall, WCK 771 was the most potent quinolone tested against the staphylococci tested, regardless of quinolone susceptibility.

Presse Med, 2004 Jul 10, 33(12 Pt 2), 2S10 - 7
{Challenges, treatment strategies and clinical progression of MRSA bacteremia}; Pittet D; DISTURBING EPIDEMIOLOGICAL DATA: Over the past decade there has been a continuous progression in the percentage of Staphylococcus aureus strains resistant to methicillin (MRSA), a slight progression in coagulase-negative staphylococci strains resistant to methicillin and a spectacular progression of enterococci resistant to glycopeptides, not only in hospitals but also in intensive care settings . The increase in nosocomial septicemia is currently a major patient safety issue . HIGHER MORTALITY IN BACTEREMIC PATIENTS: The excess mortality globally observed in cases of bacteremia (compared with patients without bacteremia) is markedly enhanced with regard to secondary bacteremia . Bacteremia is responsible for a significant increase in the overall duration of hospitalization . PROGNOSTIC FACTORS OF STAPHYLOCOCCI BACTEREMIA: The mortality rate is significantly higher in patients in whom initial therapy was inappropriate compared with those in whom it was adequate . The isolation of MRSA strains is a negative prognostic factor . PATIENTS AT RISK OF MRSA BACTEREMIA: Independent risk factors for MRSA bacteremia include prior exposure to antibiotics, a nosocomial origin, a history of hospitalization within the 6 preceding months, and the presence of a decubitus ulcer . To avoid MRSA bacteremias related to catheters, alternatives should be found to their use, all hygiene rules should be carefully respected, the insertion point should be carefully disinfected and protected, and the catheter should be removed as rapidly as possible.

Schweiz Rundsch Med Prax, 2004 Jun 9, 93(24), 1055 - 7
{Cutaneous coagulase-negative staphylococci--always harmless?}; Ramseier E et al.; Staphylococcus lugdunensis belongs to the group of coagulase-negative staphylococci, but share many clinical and microbiological characteristics with Staphylococcus aureus . We report two cases of chronic recurrent purulent skin infections in two females (one immunocompetent, the other HIV-infected with CD4 cell counts of 438/microl) who were treated repeatedly with antibiotic and surgical interventions, but only became free of recurrences after this was combined with a decontamination strategy.

J Med Microbiol, 2004 Sep, 53(Pt 9), 941 - 4
Prevalence of methicillin-resistant, coagulase-negative staphylococci in neonatal intensive care units: findings from a tertiary care hospital in India; Jain A et al.; This study was undertaken to determine the antimicrobial resistance pattern and species of coagulase-negative staphylococci (CNS) isolated from the blood and skin of neonates with clinical suspicion of late-onset septicaemia (>72 h post-delivery) admitted to neonatal intensive care units, with particular reference to the phenotypic and genotypic expression of methicillin resistance . Blood culture specimens were collected by venipuncture from 660 such neonates in brain heart infusion broth . Skin swabs from axillae were obtained from 60 neonates and inoculated on mannitol salt agar . All CNS thus obtained were further identified and antibiotic sensitivity was performed according to NCCLS recommendations . PCR for the mecA gene was carried out on 54 randomly selected isolates . Staphylococcus haemolyticus was the commonest species (34 %) followed by Staphylococcus epidermidis (24 %) amongst blood isolates . All blood isolates were sensitive to glycopeptides . Resistance to penicillin and methicillin was 94 and 66 %, respectively . Similar biotypes and antimicrobial resistance patterns were observed in skin isolates . All phenotypically methicillin-resistant isolates had the mecA gene and two of the phenotypically methicillin-sensitive isolates were also positive for mecA . A PCR assay for detection of the mecA gene in CNS may be a beneficial adjunct to standard susceptibility testing for timely and reliable detection of methicillin resistance . Given the large number of methicillin-resistant CNS, inclusion of vancomycin in empiric therapy for neonates with late-onset septicaemia may be justified.

Biochemistry (Mosc), 2004 Jul, 69(7), 754 - 6
Michaelis-menten kinetics for determining enzymatic activity of lysostaphin; Surovtsev VI et al.; The rate of lysostaphin-catalyzed lysis of staphylococci follows the Michaelis-Menten equation at {E}(0) << {S}(0), i.e., the activity of the enzyme is proportional to its concentration . This equation is proposed for determining the specific activity of lysostaphin . The apparent activation energy of hydrolysis of pentaglycine bridges in Staphylococcus peptidoglycan is 77.9 kJ/mol.

Clin Infect Dis, 2004 Aug 1, 39(3), 333 - 41 Epub 2004 Jul 12.
Predictive value of blood cultures positive for coagulase-negative staphylococci: implications for patient care and health care quality assurance; Tokars JI; Interpretation of blood cultures that are positive for coagulase-negative staphylococci (CoNS) is often difficult . Predictive values for blood cultures positive for CoNS in patients with a central vascular line in place were calculated using the following rates: true bacteremia, 3%; blood culture contamination, 2%; detection of bacteremia, 80%; and catheter colonization, 2% (for blood samples obtained through a central vascular line) . Positive predictive values were 55% for 1 positive culture result of 1 culture performed, 20% for 1 positive result of 2 performed, and only 5% for 1 positive result of 3 performed . For 2 positive culture results of 2 cultures performed, the positive predictive value was 98% if both samples were obtained through the vein, 96% if one sample was obtained through a catheter and the other was obtained by vein, and only 50% if both samples were obtained through a catheter . Use of this model with institution-specific values for input parameters would assist in clinical decision-making as well as hospital quality assurance.

Nephrol Dial Transplant, 2004 Oct, 19(10), 2584 - 91 Epub 2004 Aug 10.
Peritoneal dialysis-associated peritonitis in Scotland (1999-2002); Kavanagh D et al.; BACKGROUND: Peritonitis is a major complication of peritoneal dialysis (PD) . We have performed a national study of all patients on PD in Scotland over a 3.5 year period examining the causes of technique failure, rates of peritonitis, causative organisms, clinical outcomes and differences between automated peritoneal dialysis (APD) and continuous ambulatory peritoneal dialysis (CAPD) . METHODS: All 10 adult renal units in Scotland participated in the study and the data include all 1205 patients who were on PD in Scotland from January 1999 to June 2002 . The data were collected prospectively by the PD nurses and reported to the Scottish Renal Registry every 6 months . RESULTS: Refractory or recurrent peritonitis was the cause of technique failure in 167 patients (42.6% of all cases of technique failure) . There were 928 cases of peritonitis in 1487 patient-years, which equates to an overall peritonitis rate of one episode every 19.2 months . The peritonitis rates for APD and CAPD were similar at one episode every 20.3 months and one episode every 18.6 months, respectively . These results include 88 cases of peritonitis due to relapse or re-infection . There was a statistically significant difference (P = 0.012) in peritonitis rates between units using nasal mupiricin (one episode every 21.9 months) and those that did not (one episode every 18.3 months) . Coagulase-negative Staphylococcus was the most common cause of peritonitis (29%), although this rate is lower than in historic studies . The overall initial cure rate was 75% . The initial cure rate for APD was 77.2% and for CAPD was 73.7% . No causative organism was isolated in 17% of cases . CONCLUSION: PD-associated peritonitis is the leading cause of technique failure in Scotland . We validate previous studies showing a decrease in the proportion of peritonitis episodes that are caused by coagulase-negative staphylococci . APD peritonitis rates are not significantly better than CAPD peritonitis rates in Scotland, and the initial cure rates for APD and CAPD are similar.

Am J Clin Dermatol, 2004, 5(4), 239 - 59
Methicillin-resistant Staphylococcus aureus: impact on dermatology practice; Gosbell IB; Methicillin (meticillin)-resistant Staphylococcus aureus (MRSA) emerged in the 1960s and is now commonly seen in hospitals, clinics and, since the mid-1990s, the community . Risk factors for the acquisition of MRSA include chronic dermatoses, underlying medical illnesses, attending healthcare facilities, use of prescription antibacterials, surgery, intravenous lines, hospitalization in an intensive care unit, and proximity to patients colonized with MRSA . Recent community-associated strains often occur in patients without these risk factors . Staphylococci are readily spread from person to person and readily contaminate the environment . Infection control measures thus involve identifying the infected patients, separating them from other non-infected patients, cleaning of the environment and, most important of all, scrupulous attention to hand hygiene . Alcoholic antiseptic hand rubs offer an alternative to antiseptic hand washes and increase compliance . Treatment of MRSA skin infections is challenging . Topical agents such as mupirocin or fusidic acid can be used, but the organisms often become resistant . Systemic therapy involves non-beta-lactams . Parenteral treatment is generally with glycopeptides such as vancomycin; oral therapy is more complex . Monotherapy with quinolones, rifampin (rifampicin), and fusidic acid often results in the development of resistance and so, if any of these agents are chosen it should be in combination . There are no data on combination therapy, although rifampin-containing combinations are often chosen . Fourth-generation quinolones and linezolid are expensive but promising alternatives.

Vet Microbiol, 2004 Aug 19, 102(1-2), 33 - 42
Antimicrobial susceptibility of mastitis pathogens from first lactation and older cows; Rajala-Schultz PJ et al.; Increasing antimicrobial resistance has become a serious concern worldwide and antimicrobial use in animal agriculture is currently under scrutiny . Mastitis is the most common reason for antibiotic use in dairy herds and thus, antimicrobial resistance of mastitis pathogens has received recent attention . The purpose of this study was to describe and compare antimicrobial susceptibility of mastitis pathogens isolated at calving from first lactation and older cows . A total of 202 bacteria were isolated from intramammary infections (IMIs) within 3 days after calving over a 16-month study period in the Krauss Dairy Research Herd at the Ohio Agricultural Research and Development Center (OARDC) in Wooster, OH . Of these IMIs, 78% were caused by coagulase-negative staphylococci (CNS) . Forty-four percent of them were resistant to at least one antibiotic . Most resistance was observed against penicillin, 39% of the isolates from older cows and 26% from first lactation cows being resistant to penicillin (P > 0.05) . Also MIC90 for penicillin was higher among isolates from older cows . On the other hand, resistance to tetracycline was more common and MIC90 higher among isolates from first lactation cows than from older cows . Differences in the proportions of resistant isolates between first lactation and older cows were not statistically significant, though . The resistance patterns of the CNS isolated during the study are concordant with antimicrobial usage in the study herd . This is in agreement with the generally accepted notion that selection pressure from the use of antibiotics is a main factor in development of antibiotic resistance.

Scand J Infect Dis, 2004, 36(5), 365 - 71
Use of inflammatory markers for early detection of bacteraemia in patients with febrile neutropenia; Persson L et al.; The aim of the study was to evaluate the ability of procalcitonin, C-reactive protein, serum amyloid A, interleukin-6 and interleukin-8 to predict bacteraemia during the 2 first d of fever in neutropenic patients . A total of 94 febrile neutropenic episodes in 60 patients were studied . Plasma samples were analysed at 10-h intervals from the onset of fever . Clinical events were categorized into 4 groups: 1) bacteraemia caused by other agents than coagulase-negative staphylococci (non-CNS bacteraemia) (n = 21), 2) coagulase-negative staphylococci bacteraemia (n = 15), 3) microbiologically or clinically documented infection without bacteraemia (n = 26) and 4) fever of unknown origin (n = 32) . In non-CNS bacteraemia all markers, except for serum amyloid A, showed significantly higher levels compared to patients with fever of unknown origin (p < 0.05) . For non-CNS bacteraemia the highest negative predictive value was found for procalcitonin (94%), followed by interleukin-6 (89%), C-reactive protein (88%) and interleukin-8 (87%) . Procalcitonin, with a cut-off level of 1.4 ng/ml during 10-20 h after fever onset, showed the highest positive predictive value (67%) for a non-CNS bacteraemia . In conclusion, the value of the analysed markers to predict a non-CNS bacteraemia in neutropenic patients was limited due to low sensitivity and positive predictive value . However, procalcitonin, interleukin-6, C-reactive protein, and interleukin-8 could give useful information for the clinician in excluding a non-CNS bacteraemia.

Intensive Care Med, 2004 Oct, 30(10), 1891 - 9 Epub 2004 Jul 20.
Benefits of minocycline and rifampin-impregnated central venous catheters . A prospective, randomized, double-blind, controlled, multicenter trial; Leon C et al.; OBJECTIVE: To determine the efficacy of minocycline and rifampin-impregnated catheters compared to non-impregnated catheters in critically ill patients . DESIGN: Prospective, randomized, double-blind, controlled, multicenter trial . SETTING: Intensive care units of seven acute-care teaching hospitals in Spain . PATIENTS . Intensive care unit patients requiring triple-lumen central venous catheter for more than 3 days . INTERVENTIONS: At catheter insertion, 228 patients were randomized to minocycline and rifampin-impregnated catheters and 237 to non-impregnated catheters . Skin, catheter tip, subcutaneous segment, hub cultures, peripheral blood and infusate cultures were performed at catheter withdrawal . The rate of colonization, catheter-related bloodstream infection (CRBSI) and catheter-related clinical infectious complications (purulence at the insertion site or CRBSI) were assessed . MEASUREMENTS AND MAIN RESULTS: In the intention-to-treat analysis (primary analysis), the episodes per 1000 catheter days of clinical infectious complications decreased from 8.6 to 5.7 (RR =0.67, 95% CI 0.31-1.44), CRBSI from 5.9 to 3.1 (RR =0.53, 95% CI 0.2-1.44) and tip colonization from 24 to 10.4 (RR =0.43, 95% CI 0.26-0.73) . Antimicrobial-impregnated catheters were associated with a significant decrease of coagulase-negative staphylococci colonization (RR =0.24, 95% CI 0.13-0.45) and a significant increase of Candida spp . colonization (RR =5.84, 95% CI 1.31-26.1) . CONCLUSIONS: The use of antimicrobial-impregnated catheters was associated with a significantly lower rate of coagulase-negative staphylococci colonization and a significant increase in Candida spp . colonization, although a decrease in CRBSI, increase in 30-day survival or reduced length of stay was not observed.

Antimicrob Agents Chemother, 2004 Aug, 48(8), 2973 - 9
Relationship between triclosan and susceptibilities of bacteria isolated from hands in the community; Aiello AE et al.; The possible association between triclosan and bacterial susceptibility to antibiotic was examined among staphylococci and several species of gram-negative bacteria (GNB) isolated from the hands of individuals in a community setting . Hand cultures from individuals randomized to using either antibacterial cleaning and hygiene products (including a hand soap containing 0.2% triclosan) or nonantibacterial cleaning and hygiene products for a 1-year period were taken at baseline and at the end of the year . Although there was no statistically significant association between triclosan MICs and susceptibility to antibiotic, there was an increasing trend in the association the odds ratios (ORs) for all species were compared at baseline (OR = 0.65, 95% confidence interval {95%CI} = 0.33 to 1.27) versus at the end of the year (OR = 1.08, 95%CI = 0.62 to 1.97) and for GNB alone at baseline(OR = 0.66, 95%CI = 0.29 to 1.51) versus the end of year (OR = 2.69, 95%CI = 0.78 to 9.23) regardless of the hand-washing product used . Moreover, triclosan MICs were higher in some of the species compared to earlier reports on household, clinical, and industrial isolates, and some of these isolates had triclosan MICs in the range of concentrations used in consumer products . The absence of a statistically significant association between elevated triclosan MICs and reduced antibiotic susceptibility may indicate that such a correlation does not exist or that it is relatively small among the isolates that were studied . Still, a relationship may emerge after longer-term or higher-dose exposure of bacteria to triclosan in the community setting.

J Infect Dis, 2004 Aug 15, 190(4), 748 - 55 Epub 2004 Jul 19.
Activity of Staphylococcus epidermidis phenol-soluble modulin peptides expressed in Staphylococcus carnosus; Otto M et al.; Staphylococcus epidermidis releases a group of peptides termed phenol-soluble modulin (PSM) that stimulate macrophages . The structure of 3 peptides (PSM alpha, PSM beta, and PSM gamma ) have been described . We report a fourth peptide (PSM delta ), which is a 23mer with the structure fMSIVSTIIEVVKTIVDIVKKFKK . The gene for each of the 4 peptides was introduced singly into Staphylococcus carnosus, and the PSM-like activity of culture medium and bacterial extract were significantly greater than those of the parent strain . PSM peptides from each of the S . carnosus-expressing strains were purified and analyzed by liquid chromatography-mass spectrometry . The products, which appeared to form aggregates, were active in the activation of human immunodeficiency virus type 1 long-terminal repeat and the production of tumor necrosis factor- alpha by the macrophage cell line THP-1 . These findings suggest that PSM peptides are responsible, in part, for the modulin-like activity of staphylococci and may contribute to the development of severe staphylococcal sepsis.

J Med Microbiol, 2004 Aug, 53(Pt 8), 761 - 8
Antimicrobial-resistance and enterotoxin-encoding genes among staphylococci isolated from expressed human breast milk; Carneiro LA et al.; Resistance traits and the presence of enterotoxin-encoding genes were investigated in staphylococcus isolates obtained from expressed human breast milk . A total of 54 staphylococcal isolates identified as Staphylococcus epidermidis (53.6 %), Staphylococcus warneri (20.4 %), Staphylococcus haemolyticus (13 %) and Staphylococcus aureus (13 %) were investigated . By using a disc-diffusion method, higher rates of resistance, including intermediate resistance, were observed for penicillin (87 %) and erythromycin (59.3 %) . All strains were susceptible to clindamycin and vancomycin . Minimal inhibitory concentration (MIC) was determined by a macrodilution method for four clinically relevant antimicrobial drugs . High rates of resistance or intermediate resistance were observed for erythromycin, gentamicin and oxacillin . Additionally, three isolates showed reduced susceptibility to vancomycin (MIC, 8 microg ml(-1)) . Genetic determinants of resistance were detected by using PCR and the results showed good correlation with the macrodilution tests . Moreover, in four staphylococcus isolates, the presence of enterotoxin-encoding genes (seg, seh and sea) was identified . The results demonstrated that expressed human breast milk can be a reservoir of multiresistant staphylococci that may also harbour important virulent determinants .

Expert Opin Investig Drugs, 2004 Aug, 13(8), 973 - 85
Cephalosporins in clinical development; Page MG; Bacterial resistance to established classes of antibiotics in clinical use is continuing to increase, making the need for new agents that can be used to treat the newly multi-drug resistant organisms steadily more urgent . Cephalosporins have been a successful group of antibiotics since they were first introduced to combat drug-resistant organisms, including staphylococci . The history of cephalosporins has emphasised an improvement of their stability towards beta-lactamases, thus expanding their spectrum of activity against important Gram-negative pathogens . New cephalosporins that have potent activity against multi-resistant Gram-positive bacteria, including methicillin-resistant staphylococci and penicillin-resistant pneumococci have recently entered clinical development . At least two of these, BAL-5788 and S-3578, also have Gram-negative activity, which is comparable to that of the third-and fourth-generation cephalosporins, making them broad-spectrum agents that could be used in hospital infections where methicillin-resistant staphylococci is likely to be present.

J Hosp Infect, 2004 Aug, 57(4), 325 - 31
Catheter-related bloodstream infection in adult haematology patients: catheter removal practice and outcome; Coyle VM et al.; The aim of the present study was to describe the practice of central venous catheter (CVC) removal and outcomes of catheter-related bloodstream infection (CR-BSI) in adult haematology patients . Patients were identified retrospectively according to diagnosis coding of inpatient episodes and evaluated when, on examination of medical records, there had been evidence of sepsis with strong clinical suspicion that the source was the CVC . Demographic and bacteriological data, as well as therapeutic measures and clinical outcomes, were recorded . One hundred and three patient episodes were evaluated . The most frequent type of CVC was the Hickman catheter and the most frequently isolated pathogen was coagulase-negative staphylococci . Twenty-five percent of episodes were managed with catheter removal . Treatment failure, defined as recurrence of infection within 90 days or mortality attributed to sepsis within 30 days, occurred significantly more frequently in the group managed without catheter removal (52.5% versus 4%, P < 0.05) . Specifically, 90-day recurrence was more common when the catheter was retained (46% versus 0%) . However the difference in 30-day attributable mortality (7% versus 4%) was not significantly different . Notably, no significant difference between the two groups emerged in respect of other measured characteristics that had been considered as potential determinants of outcome . More frequent CVC removal for CR-BSI, in this population, should be considered . Management of CR-BSI without catheter removal is associated with treatment failure, morbidity and carries significant resource implications.

Endocr Pract, 2002 Nov-Dec, 8(6), 424 - 8
Bacterial pituitary abscess: an unusual cause of panhypopituitarism; Hernandez I et al.; OBJECTIVE: To describe a case of primary bacterial pituitary abscess manifesting as hypopituitarism . METHODS: We present the case history, hormonal and bacteriologic data, and findings on imaging studies in a 34-year-old man . RESULTS: The patient had an 8-month history of intermittent fever, headache, nausea, vomiting, and weight loss . Because a computed tomographic scan of the head showed a cystic sellar mass with ring enhancement, he was referred to our medical center . On physical examination, he showed signs of meningeal irritation and had mild hypotension . Hormonal evaluation revealed evidence of hypocortisolism, hypothyroidism, and hypogonadism . Three weeks after treatment with antibiotics and hormonal replacement, he underwent transsphenoidal surgical exploration and evacuation of purulent material from the sella . On culture, this specimen grew coagulase-negative staphylococci and Propionibacterium granulosum . Nine months later, dynamic testing showed persistent central hypocortisolism, hypothyroidism, and hypogonadism . CONCLUSION: Bacterial pituitary abscess is rare but manifests similar to other pituitary masses with headaches, visual field defects, and hormonal disturbances . For the correct preoperative diagnosis of this condition, the physician must have a high index of suspicion, and the characteristic ring enhancement must be present on imaging studies.

Nat Med, 2004 Aug, 10(8), 842 - 8 Epub 2004 Jul 11.
Staphylococcus aureus protein A induces airway epithelial inflammatory responses by activating TNFR1; Gomez MI et al.; Staphylococcus aureus is a major human pathogen that is associated with diverse types of local and systemic infection characterized by inflammation dominated by polymorphonuclear leukocytes . Staphylococci frequently cause pneumonia, and these clinical isolates often have increased expression of protein A, suggesting that this protein may have a role in virulence . Here we show that TNFR1, a receptor for tumor-necrosis factor-alpha (TNF-alpha) that is widely distributed on the airway epithelium, is a receptor for protein A . We also show that the protein A-TNFR1 signaling pathway has a central role in the pathogenesis of staphylococcal pneumonia.

J Clin Microbiol, 2004 Jul, 42(7), 3356 - 8
Quality control guidelines for BAL9141 (Ro 63-9141), an investigational cephalosporin, when reference MIC and standardized disk diffusion susceptibility test methods are used; Anderegg TR et al.; BAL9141 is a novel cephalosporin with a broad spectrum of activity, including activity against methicillin-resistant staphylococci . This multicenter study was performed to establish quality control (QC) guidelines for susceptibility testing of BAL9141 in phase 3 clinical trials and after U.S . Food and Drug Administration approval . The proposed 3 or 4 log(2) dilution MIC ranges encompass 97.8 to 100.0% of reported results, while the proposed 7- to 9-mm-zone-diameter QC ranges included 95.2 to 99.4% of the participant-reported disk diffusion results.

Infect Control Hosp Epidemiol, 2004 Jun, 25(6), 504 - 11
Airborne dispersal as a novel transmission route of coagulase-negative staphylococci: interaction between coagulase-negative staphylococci and rhinovirus infection; Bischoff WE et al.; OBJECTIVE: To investigate whether rhinovirus infection leads to increased airborne dispersal of coagulase-negative staphylococci (CoNS) . DESIGN: Prospective nonrandomized intervention trial . SETTING: Wake Forest University School of Medicine, Winston-Salem, North Carolina . PARTICIPANTS: Twelve nasal Staphylococcus aureus-CoNS carriers among 685 students screened for S . aureus nasal carriage . INTERVENTIONS: Participants were studied for airborne dispersal of CoNS in a chamber under three conditions (street clothes, sterile gown with a mask, and sterile gown without a mask) . After 2 days of pre-exposure measurements, volunteers were inoculated with a rhinovirus and observed for 14 days . Daily quantitative nasal and skin cultures for CoNS and nasal cultures for rhinovirus were performed . In addition, assessment of cold symptoms was performed daily, mucous samples were collected, and serum titers before and after rhinovirus inoculation were obtained . Sneezing, coughing, and talking events were recorded during chamber sessions . RESULTS: All participants had at least one nasal wash positive for rhinovirus and 10 developed a symptomatic cold . Postexposure, there was a twofold increase in airborne CoNS (P = .0004), peaking at day 12 . CoNS dispersal was reduced by wearing a gown (57% reduction, P < .0001), but not a mask (P = .7) . Nasal and skin CoNS colonization increased after rhinovirus infection (P < .05) . CONCLUSIONS: We believe this is the first demonstration that a viral pathogen in the upper airways can increase airborne dispersal of CoNS in nasal S . aureus carriers . Gowns, gloves, and caps had a protective effect, whereas wearing a mask did not further reduce airborne spread.

Int J Food Microbiol, 2004 Aug 15, 95(1), 95 - 102
Microbiological conditions of mechanically tenderized beef cuts prepared at four retail stores; Gill CO et al.; A group of 25 retail cuts of mechanically tenderized beef prepared during usual commercial operations at store facilities were obtained from each of four retail stores . Aerobes, coliforms, Escherichia coli and organisms that formed black or grey colonies on Harlequin agar (HA), a medium formulated for the recovery of Listeria, were enumerated in samples from the surfaces and the deep tissues of cuts . For the four groups of cuts, the mean numbers of aerobes on the surfaces of cuts differed by <1 log unit, but the numbers of aerobes recovered from the deep tissues differed by up to 2 log units . Few coliforms, E . coli or organisms that formed black or grey colonies on HA, which were mostly staphylococci, were recovered from surfaces and very few or none were recovered from deep tissues . Meat from the stores which provided product with the least or most bacteria in the deep tissues were cooked to maximum central temperatures that ranged from >63 to <68 degrees C . Cooking reduced the numbers of aerobes in the deep tissues of most portions to <1 log cfu/10 g . Cooking to a medium rare condition may be adequate for assuring the microbiological safety of mechanically tenderized beef that is prepared without excessive contamination of deep tissues.

J Appl Microbiol, 2004, 97(2), 271 - 84
Diversity and dynamics of communities of coagulase-negative staphylococci in traditional fermented sausages; Blaiotta G et al.; AIMS: Evaluation of composition and evolution of the coagulase-negative staphylococci (CNS) communities in two traditionally fermented sausages (salsiccia and soppressata lucana) produced in Basilicata, southern Italy . METHODS AND RESULTS: A culture-dependent approach based on isolation on selective media and identification with phenotypic and molecular methods was used . Phenotypic data of 471 strains were analysed by multivariate statistical methods by using 28 strains from culture collections and 48 strains identified by molecular methods (such as 16S rDNA sequencing, species-specific PCR assays, intergenic spacer region-PCR and PCR-denaturing gradient gel electrophoresis) as a reference . The CNS microflora of the sausages was found to be dominated by different biotypes of Staphylococcus xylosus (51.2%), followed by S . pulvereri/vitulus, S . equorum and S . saprophyticus (13.4, 10.2 and 10%, respectively) . Other species (S . succinus, S . pasteuri, S . epidermidis, S . warneri and Macrococcus caseolyticus) were also present at lower levels . Identification of 25% of the isolates was impossible . CONCLUSIONS: The composition of CNS communities varied significantly with sausage type, plant and ripening time and clear differences were found among communities of salsiccia and soppressata at the end of ripening . SIGNIFICANCE AND IMPACT OF THE STUDY: Phenotypic characterization, supported by molecular and statistical analyses, can be considered a useful approach for typing a large number of isolates and for monitoring the evolution of staphylococcal communities during sausage fermentation but does not always provide a satisfactory identification of the isolates.

Orthopedics, 2004 Jun, 27(6), 565 - 8
Methicillin-resistant staphylococcal infections: an important consideration for orthopedic surgeons; Shams WE et al.; Postoperative infections in joint prostheses and fracture-fixation devices commonly involve both MRSA and methicillin resistant coagulase-negative staphylococcus . In addition, community-acquired MRSA has also become an important consideration when infected patients are admitted to the hospital from the community . Preoperative colonization with MRSA and methicillin resistant coagulase-negative staphylococcus increases the risk of postoperative surgical site infections in orthopedic patients . Up to 5.3% of orthopedic patients are colonized with these organisms on hospital admission . Screening and decolonization of methicillin resistant staphylococci decrease the incidence of postoperative surgical site infections in the orthopedic patient . This may be particularly important in orthopedic implants given the difficulty encountered in treating infected prosthesis . Current US guidelines advocate screening for methicillin resistant staphylococci only when risk factors are present . Growing evidence suggests that screening and decolinization of all patients having elective orthopedic procedures, especially those including prosthetic implants, will decrease the incidence of postoperative infections . The infected prosthesis may be potentially salvaged if the clinical manifestations of infection have been present for < or = 10 days, the implant is stable, and the etiologic organisms are susceptible to oral antibiotics.

Biol Neonate, 2004, 86(3), 160 - 4 Epub 2004 Jun 25.
Nitric oxide levels in preterm and term infants and in premature infants with bacteremia; Marom D et al.; OBJECTIVE: To determine the serum nitric oxide levels in healthy neonates and in infants with bacteremia . METHODS: We performed a prospective study in a tertiary neonatal intensive care unit . The serum nitric oxide levels were measured in all infants at birth (basal) and in the infected neonates also on the first 2 days of bacteremia . RESULTS: Thirty-three neonates (10 term, 23 preterm) were included . Eleven preterm infants (mean gestational age 27 weeks) had bacteremia . The main blood culture isolates included coagulase-negative staphylococci (n=4), Klebsiella pneumoniae (n=3), and Escherichia coli (n=3) . The serum nitric oxide levels increased during infection in 10 infants (p <0.008) . The mean nitric oxide level before infection was 44 microM and during infection 96 microM (p=0.008) . In the healthy babies, the mean nitric oxide level was 26 microM in those with a gestational age <27 weeks, 44 microM in those born between 28 and 36 weeks of gestation, and 63 microM in term infants . CONCLUSIONS: Bacteremic preterm infants produce significantly higher amounts of nitric oxide . The basal nitric oxide levels at birth may be correlated with gestational age.

Folia Microbiol (Praha), 2004, 49(2), 123 - 31
Plasmids of Staphylococcus cohnii isolated from the intensive-care unit; Szewczyk EM et al.; Numerous isolates of both subspecies of Staphylococcus cohnii were found in the environment of the intensive-care unit of a pediatric hospital . These isolates carried in their cells many plasmids, up to fourteen, of a wide range of sizes (< 2 to > 56 kb) . Striking was the occurrence of large plasmids not very common in staphylococci . These were present in > 80% of S . cohnii isolates . Fifty-two different plasmid profiles were found in 79 investigated isolates belonging to S . cohnii ssp . cohnii and S . cohnii ssp . urealyticus . Isolates similar in plasmid profiles were grouped in antibiotic-resistance clusters established for 9 antibiotics (gentamicin, ciprofloxacin, clindamycin, erythromycin, tetracycline, chloramphenicol, mupirocin, trimethoprim-sulfamethoxazole, vancomycin) using the method of unweighted pair group mathematical averages (UPGMA) . Many isolates were multiresistant to antibiotics and produced bacteriocins.

Bioorg Med Chem Lett, 2004 Aug 2, 14(15), 3937 - 41
Definition of the heterocyclic pharmacophore of bacterial methionyl tRNA synthetase inhibitors: potent antibacterially active non-quinolone analogues; Jarvest RL et al.; Potent inhibitors of bacterial methionyl tRNA synthetase (MRS) have previously been reported . Through SAR of the quinolone moiety, the right hand side pharmacophore for MRS inhibition has now been defined as an NH-C-NH functionality in the context of a bicyclic heteroaromatic system . Potent antibacterial fused-pyrimidone and fused-imidazole analogues have been obtained and enantioselective activity demonstrated . Compound 46 demonstrated very good antibacterial activity against panels of antibiotic-resistant staphylococci and enterococci.

Orv Hetil, 2003 Jan 19, 144(3), 107 - 15
{Methicillin-resistance of staphylococci and methods of detection}; Fehervarine TM et al.; In Hungary more than 25% of Staphylococcus aureus strains and 33.4-70.1% of strains of different coagulase-negative Staphylococcus species isolated from inpatients in the last five years were methicillin-resistant . These are great clinical problems because the methicillin-resistant strains are resistant to all beta-lactam antibiotics, furthermore, most of them exhibit multiple resistance, too . For these reasons, the fast and exact microbiological diagnosis is of utmost basic and life-saving importance . In this review the most important evidences for proving pathogenicity and virulence of methicillin-resistant S . aureus strains and our knowledge on the origin, genetic background, conditions of expression, forms of appearance, phenotypical and genotypical properties of methicillin resistance are summarised . Phenotypical semiquantitative and quantitative methods aiming the detection of methicillin resistance are shown with their advantages and restrictions . Genetic methods applicable to detect mecA gene responsible for coding methicillin resistance, furthermore, those by which clonal and genomic relationship and spread can be proven in epidemic cases are presented . Finally, up-to-date schemes for a proper identification as well as systemic and local elimination of methicillin resistant Staphylococcus strains are suggested.

Antimicrob Agents Chemother, 2004 Jul, 48(7), 2719 - 23
In vitro activities of a novel cephalosporin, CB-181963 (CAB-175), against methicillin-susceptible or -resistant Staphylococcus aureus and glycopeptide-intermediate susceptible staphylococci; Huang V et al.; We examined the activity of CB-181963, a novel cephalosporin, against methicillin-resistant Staphylococcus aureus (MRSA) (n = 200), methicillin-susceptible S . aureus (MSSA) (n = 50), glycopeptide-intermediate Staphylococcus species (GISS) (n = 47), and VRSA (n = 2) isolates . CB-181963 exhibited MIC profiles similar to those of linezolid against MRSA and GISS; however, activity against MSSA was similar to that of vancomycin . Time-kill study results of investigations of activity against MRSA, MSSA, and GISS at 24 h were as follows: CB-181963 activity = vancomycin activity > linezolid activity (P < 0.001); CB-181963 = quinupristin-dalfopristin = vancomycin > linezolid (P < 0.05); CB-181963 > linezolid (P = 0.003); and CB-181963 = quinupristin-dalfopristin = vancomycin . CB-181963 may provide an alternative treatment for multidrug-resistant staphylococci.

Antimicrob Agents Chemother, 2004 Jul, 48(7), 2551 - 7
Beneficial influence of platelets on antibiotic efficacy in an in vitro model of Staphylococcus aureus-induced endocarditis; Mercier RC et al.; Platelets contribute to antimicrobial host defense against infective endocarditis (IE) by releasing platelet microbicidal proteins (PMPs) . We investigated the influence of thrombin-stimulated human platelets on the evolution of simulated IE in the presence and absence of vancomycin or nafcillin . Staphylococcus aureus strains differing in intrinsic susceptibility to PMPs or antibiotics were studied: ISP479C (thrombin-induced PMP-1 {tPMP-1} susceptible; nafcillin and vancomycin susceptible), ISP479R (tPMP-1 resistant; nafcillin and vancomycin susceptible), and GISA-NJ (tPMP-1 intermediate-susceptible; vancomycin intermediate-susceptible) . Platelets were introduced and thrombin activated within the in vitro IE model 30 min prior to inoculation with S . aureus . At 0 to 24 h postinoculation, bacterial densities in chamber fluid and simulated endocardial vegetations (SEVs) were quantified and compared among groups . Activated platelets alone, or in combination with antibiotics, inhibited the proliferation of ISP479C in chamber fluid or SEVs over the initial 4-h period (P < 0.05 versus controls) . Moreover, nafcillin-containing regimens exerted inhibitory effects beyond 4 h against ISP479C in both model phases . By comparison, activated platelets inhibited GISA-NJ proliferation in SEVs but not in chamber fluid . The combination of platelets plus nafcillin or vancomycin significantly inhibited proliferation of the GISA-NJ strain in SEVs compared to the effect of platelets or antibiotics alone (P < 0.05) . In contrast, platelets did not significantly alter the antistaphylococcal efficacies of nafcillin or vancomycin against ISP479R . These data support our hypothesis that a beneficial antimicrobial effect may result from the interaction among platelets, PMPs, and anti-infective agents against antibiotic-susceptible or -resistant staphylococci that exhibit a tPMP-1-susceptible or -intermediate-susceptible phenotype.

Clin Microbiol Infect, 2004 Jul, 10(7), 667 - 70
Blood culture results during the period 1995-2002 in a Greek tertiary care hospital; Hadziyannis AS et al.; Data on BacT/Alert blood cultures in a Greek hospital from 1995 to 2002 were analysed retrospectively . There was a gradual increase in the number of blood cultures (4981 in 1995 to 9054 in 2002), the true positive rate (14.4% to 16.5%) and the number of bloodstream infections/1000 hospital admissions (22.1 to 30.7) . The five most common pathogens were Eschericia coli, Staphylococcus aureus, coagulase-negative staphylococci, enterococci and Klebsiella spp . The relative rates of Gram-negative and Gram-positive isolates inverted during the study period because of an increasing frequency of coagulase-negative staphylococci and enterococci.

Clin Microbiol Infect, 2004 Jul, 10(7), 628 - 33
Potential use of procalcitonin as a diagnostic criterion in febrile neutropenia: experience from a multicentre study; Giamarellou H et al.; In order to assess the diagnostic value of procalcitonin, 158 patients with febrile neutropenia from centres across Europe were studied . Patients with fever were diagnosed on the basis of either: (1) clinical, radiological and microbiological criteria; or (2) the procalcitonin value . In the latter case, concentrations of 0.5-1.0 ng/mL were considered diagnostic of localised infection, concentrations of 1.0-5.0 ng/mL of bacteraemia, and concentrations of > 5.0 ng/mL of severe sepsis . Procalcitonin and C-reactive protein were estimated daily in serum by immunochemiluminescence and nephelometry, respectively . Overall, the sensitivity (specificity) of procalcitonin for bacteraemia was 44.2% (64.3%) at concentrations of 1.0-5.0 ng/mL, and 83.3% (100%) for severe sepsis at concentrations of > 5.0 ng/mL . It was concluded that procalcitonin is a marker strongly suggestive of severe sepsis at concentrations of > 5.0 ng/mL . Estimated concentrations of < 0.5 ng/mL indicate that infection is unlikely, but it was observed that bacteraemia associated with coagulase-negative staphylococci may fail to elevate serum procalcitonin levels.

Chemotherapy, 2004 Jun, 50(2), 81 - 7
Addition of teicoplanin or vancomycin for the treatment of documented bacteremia due to gram-positive cocci in neutropenic patients with hematological malignancies: microbiological, clinical and economic evaluation; D'Antonio D et al.; A prospective, randomized, double-blind trial was conducted on 124 febrile patients with hematological malignancies to compare teicoplanin with vancomycin as an addition to the initial empiric amikacin-ceftazidime regimen after documented bacteremia due to gram-positive cocci . At enrollment, patients in both groups were comparable with respect to age, sex, underlying hematologic disorders and duration of neutropenia . Rates of therapeutic success were 55/63 (87.3%) in the teicoplanin group and 56/61 (91.8%) in the vancomycin group (p = 0.560) . The mean duration of treatment was similar, being 12.2 and 11.4 days, respectively (p = 0.216) . Patients treated with teicoplanin remained febrile for slightly longer than those treated with vancomycin (4.9 vs . 4.0 days) (p = 0.013) . Thirteen patients experienced an adverse drug reaction, but without any significant difference in the two arms . Isolated staphylococci showed a progressive and significant decrease in susceptibility to both glycopeptides during the 8 study years . The economic analysis performed showed that the addition of vancomycin is cost-saving .

Int J Antimicrob Agents, 2004 Jun, 23(6), 637 - 40
Antibiotic susceptibility of coagulase-negative staphylococci isolated from goats' milk; Moroni P et al.; The antibiotic susceptibility of 70 strains of coagulase-negative staphylococci (CNS) isolated during the 2001 lactating period from the milk of dairy goats, was evaluated . The antibiotics tested were benzylpenicillin, cloxacillin, amoxicillin, amoxicillin plus clavulanic acid, cephalonium and cefoperazone, erythromycin and tylmicosin, kanamycin and tetracycline . Minimum inhibitory concentration (MIC) measurements showed that all beta-lactams (except cefoperazone) were effective against Staphylococcus epidermidis and Staphylococcus caprae, whereas the other antibiotics were either less effective or showed no activity . Other CNS species showed very variable sensitivity to the antibiotics; testing would be required before therapy for the clinical control of goat mammary infections .

J Vet Pharmacol Ther, 2004 Jun, 27(3), 147 - 53
Treatment of canine pyoderma with ibafloxacin and marbofloxacin--fluoroquinolones with different pharmacokinetic profiles; Horspool LJ et al.; Dogs with superficial or deep pyoderma (n = 228) presented to first opinion veterinarians (n = 20) were treated orally with either ibafloxacin, at a dosage of 15 mg/kg, or marbofloxacin, at a dosage of 2 mg/kg, once daily for 3-16 weeks . On initial presentation, 35% of the cases were classified as having recurrent pyoderma and 40% as having deep pyoderma . Staphylococci (mainly Staphylococcus intermedius) were isolated from over 90% of the cases . The average treatment periods were 41 +/- 26 and 38 +/- 21 days in the ibafloxacin and marbofloxacin groups, respectively . One week after the cessation of treatment, 74 and 81% of dogs (P > 0.05) in the ibafloxacin and marbofloxacin groups, respectively, were classified as having responded to treatment . One month after the cessation of treatment, 70% of the dogs in each group were still classified as cured or improved, and 3 and 11% (P < 0.05) in the ibafloxacin and marbofloxacin groups, respectively, were classified as having relapsed . Despite having different pharmacokinetic profiles, ibafloxacin and marbofloxacin produced similar results when used under field conditions at the recommended dosages.

Infect Control Hosp Epidemiol, 2004 May, 25(5), 431 - 5
Emergence of resistant staphylococci on the hands of new graduate nurses; Cimiotti JP et al.; OBJECTIVE: To describe the aerobic microbial flora on the hands of experienced and new graduate nurses over time . DESIGN: A prospective cohort design that examined the relationship between duration of employment in an intensive care unit (ICU) and the microbial flora on the hands of experienced and new graduate nurses during a 23-month period . SETTING: A 50-bed, level III-IV neonatal ICU in New York City . PARTICIPANTS: Twelve experienced nurses and 9 new graduate nurses working full time in the NICU . INTERVENTION: One hundred fifty samples were obtained from the clean, dominant hands of the nurses . Cultures were performed at baseline and then quarterly for each experienced and new graduate nurse . Baseline and final cultures of Staphylococcus epidermidis were further examined using pulsed-field gel electrophoresis . RESULTS: At baseline, a significantly larger proportion of the experienced nurses had methicillin-resistant, coagulase-negative staphylococci isolated from their hands compared with the new graduate nurses (95% and 33%, respectively; P = .0004) . For a second culture, performed 1 to 4 months later, there were no longer significant differences between the two groups (82% and 54%, respectively; P = .12) . By the last culture, all staphylococcal isolates were methicillin resistant in both groups of nurses; 3 were methicillin-resistant S . aureus . CONCLUSIONS: Colonization with methicillin-resistant staphylococci occurred after brief exposure to the hospital environment, despite the use of antiseptic hand hygiene agents . Furthermore, at final culture, the two groups shared one dominant hospital-acquired strain of S . epidermidis.

Klin Lab Diagn, 2004 Apr, (4), 42 - 5
{Comparison of efficacy of three test-systems for identification of Staphylococcus: PBDS (Russia), "STAPHYtest-16" (Check Republic), "API-STAPH" (France)}; Deriabin DG et al.; The diagnostic efficiency of three test-systems designed for staphylococci identification including the definition of opportunistic errors was comparatively studied . The identification results coincidence (IRC) made, versus the reference method, 57 +/- 14% for Staphylococci Differentiation Biochemical Plate (SDBP--Russia) 73.83 +/- 3.6% for STAPHYtest-16 (Check Republic) and 58.33 +/- 5.03% for API-Staph (France) . The diagnostic efficiency of the studied test-systems was found to be in proportion with the total information density of the identification tests belonging to each of them, which could be used for determining an optimal test list that would ensure the maximum diagnostic effect with minimal cost.

Zh Mikrobiol Epidemiol Immunobiol, 2004 Mar-Apr, (2), 83 - 5
{Bacteriological pattern of acute purulent balanoposthitis in children}; Muratov ID; The microflora of the prepucial sac in 94 children (aged 2 months to 15 years) with acute purulent balanoposthitis (APB) was studied . In the overwhelming majority of cases APB in children was caused by facultative anaerobic and aerobic bacteria (96.7%); of these, Gram positive bacteria occurred most frequently (85.7% of cases) . In 51.6% of children these bacteria were represented by staphylococci, constituting 60.3% of all Gram positive flora . Gram negative bacteria were isolated in 40.6% of cases, Escherichia coli taking the first place among them . The isolated microflora was highly resistant to frequently used wide spectrum antibiotics.

Rev Port Pneumol, 2003 Sep-Oct, 9(5), 395 - 409
{Treatment and prevention of Staphylococcus aureus}; Ribeiro I et al.; The number of Staphylococcus aureus (S . aureus) community and nosocomial acquired infections have increased in the last twenty years . Between 1990 and 1992, this pathogen has become the most frequent source of nosocomial infections 1,2 . On the other hand, as result of antibiotherapy selection pressure, we observe a dramatic increase in the methicillin-resistant S . aureus (MRSA) infections 3,4 . With the recent emergence of multiresistant strains, including glycopeptides resistance, the treatment of these infections became still more difficult 2,4-6 . It's important to prevent resistant strains emergence . To prevent further emergence of resistant strains, the use of antibiotherapy must be optimised, laboratory methods for the detection of resistant pathogens must be enhanced and strict precautions should be taken following of the infection or colonization of patients 6-10 . In this paper, we review anti-staphylococci history evolution and point out the present recommendations for the treatment and prevention of Staphylococcus aureus infections and colonization.

Perit Dial Int, 2004 May-Jun, 24(3), 264 - 73
Protein adsorption on ex vivo catheters and polymers exposed to peritoneal dialysis effluent; Yanagisawa N et al.; BACKGROUND: Deposition of proteins on surfaces of medical devices has been recognized to putatively relate to the process of regulation of biomaterial-associated complications by attachment of fibrin clots, eukaryotic cells, and microbes . The molecules adsorb to a varying extent, depending not only on the physicochemical properties of the biomaterial, but also on the composition of the host fluid . OBJECTIVE: Adsorption of proteins on catheters exposed both ex vivo and in vitro to dialysate of patients on peritoneal dialysis (PD) was studied . METHODS: Peritoneal dialysis effluent was collected from 5 patients with end-stage renal disease on continuous ambulatory PD . Tenckhoff catheters were obtained from 16 patients . Deposition of proteins on excised Tenckhoff catheters and tubing of different materials exposed to PD effluent in vitro was studied using 125iodine-labeled antibodies . Adhesion of Staphylococcus aureus and Staphylococcus epidermidis strains was quantified on tubing exposed to PD effluent in vitro . RESULTS: The presence of albumin, transferrin, immunoglobulin G, fibrinogen, fibronectin, von Willebrand factor, vitronectin, and thrombospondin was determined at various concentrations in PD effluent . All proteins analyzed were detected on PD catheters removed from patients . The extent of protein deposition on Tenckhoff catheters exposed to PD effluent, in vitro, rapidly reached a plateau and remained constant, as it did on polyvinyl chloride and polyethylene tubing . Adhesion of staphylococci was enhanced on Tenckhoff catheters exposed to PD effluent compared to unused PD solution . CONCLUSIONS: The data identify surface exposed proteins that may serve as adhesion sites for microbes on peritoneal catheters indwelled in patients undergoing PD.

Epidemiol Mikrobiol Imunol, 2004, 53(2), 62 - 5
{Detection of MRSA in a group of 752 strains of S . aureus using a cefoxitin disk}; Urbaskova P et al.; A set of 752 S . aureus strains including 665 fresh clinical isolates, 82 collection strains from the NRL for staphylococci and three control strains for external quality assessment were tested for susceptibility to oxacillin by three routine phenotypic methods with oxacillin (agar screening method, dilution micromethod and disk diffusion method) and a new method with a 30 micrograms cefoxitin disk . Gene mecA coding for oxacillin resistance was detected by PCR, PBP2a gene product was detected by latex agglutination . All of 218 oxacillin resistant strains--MRSA (methicillin resistant S . aureus)--gave inhibition zones of 6-19 mm around the cefoxitin disk, i.e . zones within the range set up for oxacillin resistant strains, eight out of these strains showing false oxacillin susceptibility in one or more phenotypic tests . It can be stated that the presence of an inhibition zone of < 20 mm around the 30 micrograms cefoxitin disk allows for reliable differentiation between MRSA and oxacillin susceptible S . aureus.

J Clin Microbiol, 2004 Jun, 42(6), 2780 - 2
Evaluation of the methicillin-resistant Staphylococcus aureus (MRSA)-Screen latex agglutination test for detection of MRSA of animal origin; Lee JH et al.; Methicillin (oxacillin)-resistant staphylococci (MRS) have emerged as major clinical and epidemiological pathogens, and there have been frequent reports of MRS infections in the veterinary field . The MRSA-Screen latex agglutination test (Denka Seiken Co., Ltd., Tokyo, Japan) was compared with an oxacillin agar screen test, MIC determination, and mecA PCR assay, the "gold standard." In an analysis of 15 mecA-positive and 48 mecA-negative S . aureus animal isolates, as well as 9 mecA-positive and 147 mecA-negative, coagulase-negative staphylococcal animal isolates, the latex agglutination test surpassed the widely used oxacillin agar screen method and MIC determination, with a sensitivity and a specificity of 100% . The MRSA-Screen test is a reliable and rapid method of detecting MRS in the veterinary field.

J Clin Microbiol, 2004 Jun, 42(6), 2777 - 9
Incidence of constitutive and inducible clindamycin resistance in Staphylococcus aureus and coagulase-negative staphylococci in a community and a tertiary care hospital; Schreckenberger PC et al.; The incidences of inducible clindamycin resistance at two hospitals (an inner-city hospital and a suburban community hospital) were 7 and 12% for methicillin-resistant Staphylococcus aureus, 20 and 19% for methicillin-susceptible S . aureus, and 14 and 35% for coagulase-negative staphylococci, respectively . Given the variability of inducible resistance to clindamycin found in our two hospitals, we conclude that susceptibility testing of staphylococci should include the disk diffusion induction test (D-test).

Clin Perinatol, 2004 Mar, 31(1), 69 - 75
Immunoenhancement to prevent nosocomial coagulase-negative staphylococcal sepsis in very low-birth-weight infants; Devlin LA et al.; Extremely low-birth-weight infants are susceptible to invasion by coagulase-negative staphylococci (CONS) . This article reviews the epidemiology, immunology, and microbiology of CONS and describes recent clinical trials of immunoenhancing agents such as intravenous immunoglobulin, granulocyte colony-stimulating factor, granulocyte macrophage colony-stimulating factor, and mouse humanized chimeric anti-lipoteichoic acid antibody.Potential avenues of research to reduce the incidence of nosocomial CONS sepsis in premature neonates are presented.

Joint Bone Spine, 2004 May, 71(3), 240 - 2
Multifocal discitis caused by Staphylococcus warneri; Announ N et al.; Staphylococcus warneri is a coagulase-negative staphylococcus that is a normal inhabitant of the skin but occasionally causes septicemia and endocarditis . We report a case of multifocal discitis caused by S . warneri in an immunocompetent patient . Only three cases of spinal S . warneri infections have been reported in the literature . They illustrate the atypical clinical presentation, with chronic pain of increasing severity in the thoracic or lumbar spine instead of the abrupt onset that characterizes S . aureus discitis . In our patient, despite the multifocal distribution of the lesions, heretofore unreported, clinical presentation suggested common low back pain . This presentation may be ascribable to the unique bacteriological characteristics of S . warneri . The case reported here illustrates the diagnostic challenges sometime raised by discitis due to coagulase-negative staphylococci .

Int Microbiol, 2004 Mar, 7(1), 63 - 6
Simultaneous PCR detection of ica cluster and methicillin and mupirocin resistance genes in catheter-isolated Staphylococcus; Martin-Lopez JV et al.; Recent data show that more than 50% of catheter-associated bloodstream infections are caused by staphylococci . Staphylococcal infections produced by intercellular-adhesion cluster (ica) carriers can be even more problematic due to the presence of methicillin and mupirocin resistance genes . In the present study, a multiplex PCR protocol that allows the simultaneous identification of staphylococci and detection of both the ica and methicillin and/or mupirocin resistance genes was developed . Furthermore, the method allows differential detection of the ica locus from Staphylococcus aureus and Staphylococcus epidermidis.

Semin Pediatr Infect Dis, 2004 Jan, 15(1), 52 - 7
Penicillin: its discovery and early development; Ligon BL; In August 1928, Alexander Fleming returned from a vacation to his usually messy, disordered laboratory . In one of the Petri dishes that had not been touched by the Lysol, he noticed an unusual phenomenon: separate colonies of staphylococci and, near the dish's edge, a colony of mold approximately 20 mm in diameter . The finding proved to be a watershed in the history of medicine . This discovery lay dormant for some time before other researchers took up the challenge to investigate its clinical possibilities . Two investigators at Oxford, Sir Howard Walter Florey and Ernst Boris Chain, brought penicillin's potential for medical use to fruition and, along with Fleming, shared the 1945 Nobel Prize for Medicine . The discovery and development of penicillin represent one of the most important developments in the annals of medical history . This article presents a brief overview of the events that occurred in the progress from discovery to implementation as a therapeutic agent.

Am J Infect Control, 2004 Jun, 32(4), 215 - 9
Dissemination of nosocomial multiple-aminoglycoside-resistant Staphylococcus aureus caused by horizontal transfer of the resistance determinant (aacA/aphD) and clonal spread of resistant strains; Udou T; BACKGROUND: The multiple-aminoglycoside-resistant gene aacA/aphD exists as a transposable genetic element (Tn4001) in gram-positive cocci . Here we describe our retrospective investigation of the mechanism responsible for the dissemination of Tn4001 among staphylococci present in clinical isolates collected in our university hospital . At its peak, about 80% of the total isolates of methicillin-resistant Staphylococcus aureus showed multiple-aminoglycoside resistance, and all harbored aacA/aphD . METHODS: Clonal relatedness was analyzed by pulsed field gel electrophoresis after SmaI endonuclease digestion of the genomic DNA from isolates collected in 1991 and 1997 . To detect Tn4001 on the chromosome and conjugative plasmids, specific sequences from aacA/aphD and the insertion sequence IS256, whose inverted sequence flanks aacA/aphD, were amplified by polymerase chain reaction . RESULTS: Pulsed field gel electrophoresis of genomic DNA, plasmid analysis, and polymerase chain reaction detection of the resistance determinant all indicated the presence of disseminated clones that had survived among hospitalized patients through acquisition of conjugative plasmids harboring aacA/aphD . Furthermore, aacA/aphD also disseminated among nosocomial strains other than S aureus as a consequence of the self-transferability of Tn4001 . CONCLUSIONS: The nosocomial prevalence of multiple-aminoglycoside-resistant staphylococci is the result of both horizontal and interspecific transfer of aacA/aphD and the clonal spread and survival of resistant strains.

Am J Infect Control, 2004 Jun, 32(4), 205 - 8
Nosocomial infections among pediatric hematology/oncology patients: results of a prospective incidence study; Urrea M et al.; BACKGROUND: Nosocomial infections (NI) are an important clinical complication in adult and children patients at the different hospital wards . NI cause considerable morbidity and mortality and are associated with prolonged hospital stay and increased health care costs . OBJECTIVE: The objective of this study was to describe the incidence of NI in pediatric patients with neoplastic disease as a first step toward improving infection control policies . METHODS: A prospective surveillance study from March through May 2001 was performed in the pediatric hematology/oncology unit at the University Hospital in Barcelona . The Centers for Disease Control and Prevention criteria were used as standard definition for NI . NI rates were calculated as a density incidence rate (per 100 patient-days) . RESULTS: Fifty-one patients were admitted during the study period . Twelve patients had a total of 18 NI . The incidence of NI was 1.77 per 100 patient-days . Patients with acute lymphoblastic leukemia had the highest NI rate (2.71 per 100 patient-days) . The most frequent episodes of NI were bacteremia (55.5%) and fever of unknown origin (16.6%) . The most frequently isolated microorganisms were gram-positive bacteria (78.6%) . Coagulase-negative Staphylococci were the most common isolates in bacteremias (70%) . The extrinsic risk factors related with the highest incidence rates of NI per 100 patient-days were central venous catheterization (1.7 infections) and parenteral nutrition (3.2 infections) . CONCLUSIONS: Extrinsic risk factors associated with NI have been identified in this high-risk population . These findings suggest the need to evaluate the infection control measures to reduce the morbidity and mortality in a hematology/oncology unit.

Int J Antimicrob Agents, 2004 Mar, 23(3), 268 - 72
Antibiotic resistance and epidemiological typing of Staphylococcus aureus strains from ovine and rabbit mastitis; Goni P et al.; Mastitis is a serious problem for sheep and rabbit farms, Staphylococcus aureus being the main causal agent . Fifty strains of S . aureus isolated from sheep and rabbits from farms located in diverse geographical regions of Spain were studied . Their resistance pattern and plasmid profile was related to the pulsotypes obtained by pulsed-field gel electrophoresis (PFGE) . The results showed great heterogeneity in staphylococci isolated from sheep, both in pulse-type and plasmid profile . We found in addition, antibiotic-resistant strains and aminoglycoside-modifying enzyme (AGMEs) producer strains . The genotypes corresponding to staphylococci isolated from rabbits were less heterogeneous, although they also could be subdivided by plasmid profile and resistance patterns . Resistance to antibiotics such as methicillin or AGMEs production could indicate possible human origin of the strains or a possible source of resistant strains for human beings.

Int J Antimicrob Agents, 2004 Mar, 23(3), 247 - 53
In vitro combined bactericidal activity of cefpirome and glycopeptides against glycopeptides and oxacillin-resistant staphylococci; Bergeret M et al.; Infections caused by coagulase-negative staphylococci are becoming increasingly important, particularly those of nosocomial origin, as the organisms are frequently multi-resistant . New antimicrobial strategies are needed . The bactericidal activity of a combination of cefpirome with either vancomycin or teicoplanin against 12 strains of methicillin-resistant staphylococci with a decreased susceptibility to teicoplanin was determined in vitro by a time killing method . Strains Mu3 and Mu50 of Staphylococcus aureus were also studied . Cefpirome (0.125-0.5 x MIC) combined with vancomycin (0.25-1 x MIC) or teicoplanin (0.125-1 x MIC) acted synergically against 12 isolates over 18 h in most cases . A synergistic killing effect was also observed with the Mu3 and Mu50 strains of glycopeptide-intermediate S . aureus but over a longer period.

J Infect Chemother, 2004 Apr, 10(2), 86 - 9
A comparative evaluation of phenotypic and molecular methods for the detection of oxacillin resistance in coagulase-negative staphylococci; Ghoshal U et al.; Detection of oxacillin resistance in coagulase-negative staphylococci (C-NS) by phenotypic methods is often difficult . The present study compared the National Committee for Clinical Laboratory Standards (NCCLS) revised guidelines of phenotypic methods with a mecA-based polymerase chain reaction (PCR) for C-NS . Ninety clinical C-NS isolates were tested for oxacillin resistance by disk diffusion (1-microg disk), minimum inhibitory concentration (MIC) breakpoint (0.5 microg/ml) after 24 h, and mecA-based PCR . The sensitivity and specificity of disk diffusion was 80% and 93%, and the sensitivity and specificity of the MIC breakpoint after 24 h was 84% and 91%, respectively, against PCR as gold standard . Eleven strains (7 mecA-positive and 4 mecA-negative) showed discordant results between MIC breakpoint after 24 h and PCR . Six of the 7 mecA-positive and all 4 mecA-negative discordant strains had inducible oxacillin resistance and beta-lactamase hyperproduction, respectively . The present study concludes that inducible oxacillin resistance and beta-lactamase hyperproduction are the major causes of discordant results between phenotypic methods and mecA-based PCR, and need special attention.

Antimicrob Agents Chemother, 2004 Jun, 48(6), 1968 - 73
Epigallocatechin-gallate enhances the activity of tetracycline in staphylococci by inhibiting its efflux from bacterial cells; Sudano Roccaro A et al.; Epigallocatechin-gallate (EGCg), the major catechin present in green tea extracts, has been shown to have several antibacterial activities, limiting bacterial growth and invasion and acting in synergy with beta-lactam antibiotics . In this article, we report that EGCg at doses half and below its calculated MIC of 100 microg/ml, is able to reverse tetracycline resistance in staphylococcal isolates expressing the specific efflux pump Tet(K) and appears to improve the MICs of tetracycline for susceptible staphylococcal isolates as well . The visible effect of EGCg is an increased accumulation of tetracycline inside bacterial cells . This effect is likely due to the inhibition of pump activity, and it is evident not only for Tet(K) pumps but also for efflux pumps of a different class {Tet(B)} . In summary, our data indicate that the observed dramatic enhancement by EGCg of tetracycline activity for resistant staphylococcal isolates is caused by impairment of tetracycline efflux pump activity and increased intracellular retention of the drug, suggesting a possible use of EGCg as an adjuvant in antibacterial therapy.

J Exp Med, 2004 May 17, 199(10), 1379 - 90
Mannose-binding lectin-deficient mice are susceptible to infection with Staphylococcus aureus; Shi L et al.; Gram-positive organisms like Staphylococcus aureus are a major cause of morbidity and mortality worldwide . Humoral response molecules together with phagocytes play a role in host responses to S . aureus . The mannose-binding lectin (MBL, also known as mannose-binding protein) is an oligomeric serum molecule that recognizes carbohydrates decorating a broad range of infectious agents including S . aureus . Circumstantial evidence in vitro and in vivo suggests that MBL plays a key role in first line host defense . We tested this contention directly in vivo by generating mice that were devoid of all MBL activity . We found that 100% of MBL-null mice died 48 h after exposure to an intravenous inoculation of S . aureus compared with 45% mortality in wild-type mice . Furthermore, we demonstrated that neutrophils and MBL are required to limit intraperitoneal infection with S . aureus . Our study provides direct evidence that MBL plays a key role in restricting the complications associated with S . aureus infection in mice and raises the idea that the MBL gene may act as a disease susceptibility gene against staphylococci infections in humans.

Eur J Clin Microbiol Infect Dis, 2004 Jun, 23(6), 495 - 8 Epub 2004 May 13.
Non- epidermidis coagulase-negative staphylococcal bacteremia: clinical predictors of true bacteremia; Ruhe J et al.; In order to explore the clinical significance and risk factors for true bacteremia caused by coagulase-negative staphylococci (CNS) other than Staphylococcus epidermidis, a retrospective cohort study of 160 patients with at least one blood culture positive for non- epidermidis CNS was performed . True bacteremia was diagnosed in 32 (20%) of the patients . On multivariate analysis the following factors were associated with true bacteremia: (i) more than one positive blood culture, (ii) presence of a central venous catheter, and (iii) methicillin resistance . The results of this study indicate that non- epidermidis CNS can cause significant bloodstream infections.

FEMS Microbiol Lett, 2004 May 15, 234(2), 275 - 80
Identification and genetic characterisation of orthopaedic Staphylococcus isolates collected in Italy by automated EcoRI ribotyping; Andollina A et al.; The aim of this study was to evaluate the possibility to use automated EcoRI ribotyping to address, during the same analysis, both identification and genetic characterisation of 38 Staphylococcus aureus and 64 coagulase-negative staphylococci collected from surgical injuries . The ribotyping identification results confirmed those obtained using the API Staph system for 96% of the isolates . All strains were successfully genotyped and the ribotyping discriminatory power, calculated using the Simpson's index of discrimination, was very high for both groups of staphylococci tested . The same, as well as different biotypes, were identified among isolates with the identical ribotyping profile .

J Clin Microbiol, 2004 May, 42(5), 1875 - 84
New real-time PCR assay for rapid detection of methicillin-resistant Staphylococcus aureus directly from specimens containing a mixture of staphylococci; Huletsky A et al.; Molecular methods for the rapid identification of methicillin-resistant Staphylococcus aureus (MRSA) are generally based on the detection of an S . aureus-specific gene target and the mecA gene . However, such methods cannot be applied for the direct detection of MRSA from nonsterile specimens such as nasal samples without the previous isolation, capture, or enrichment of MRSA because these samples often contain both coagulase-negative staphylococci (CoNS) and S . aureus, either of which can carry mecA . In this study, we describe a real-time multiplex PCR assay which allows the detection of MRSA directly from clinical specimens containing a mixture of staphylococci in <1 h . Five primers specific to the different staphylococcal cassette chromosome mec (SCCmec) right extremity sequences, including three new sequences, were used in combination with a primer and three molecular beacon probes specific to the S . aureus chromosomal orfX gene sequences located to the right of the SCCmec integration site . Of the 1,657 MRSA isolates tested, 1,636 (98.7%) were detected with the PCR assay, whereas 26 of 569 (4.6%) methicillin-susceptible S . aureus (MSSA) strains were misidentified as MRSA . None of the 62 nonstaphylococcal bacterial species or the 212 methicillin-resistant or 74 methicillin-susceptible CoNS strains (MRCoNS and MSCoNS, respectively) were detected by the assay . The amplification of MRSA was not inhibited in the presence of high copy numbers of MSSA, MRCoNS, or MSCoNS . The analytical sensitivity of the PCR assay, as evaluated with MRSA-negative nasal specimens containing a mixture of MSSA, MRCoNS, and MSCoNS spiked with MRSA, was approximately 25 CFU per nasal sample . This real-time PCR assay represents a rapid and powerful method which can be used for the detection of MRSA directly from specimens containing a mixture of staphylococci.

Bioorg Med Chem Lett, 2004 Jun 7, 14(11), 2863 - 6
Potent DNA gyrase inhibitors; novel 5-vinylpyrazole analogues with Gram-positive antibacterial activity; Tanitame A et al.; In this study, we designed and synthesized novel 5-vinylpyrazole analogues by decreasing the lipophilicity of the parent compounds 1a,b; 3-{(3-methoxycarbonyl)cyclohexylaminomethyl}indazoles while keeping the van der Waals interaction with the lipophilic area of DNA gyrase B . The selected compound 8bb exhibited good antibacterial activity against staphylococci and enterococci, including multi-drug resistant strains.

Pediatrics, 2004 May, 113(5), 1195 - 203
The effect of prophylactic ointment therapy on nosocomial sepsis rates and skin integrity in infants with birth weights of 501 to 1000 g; Edwards WH et al.; OBJECTIVE: Extremely low birth weight infants have a high risk of developing nosocomial bacterial sepsis (NBS) . Immature fragile skin may represent an inadequate protective barrier to bacteria colonizing the skin . We conducted a randomized, multicenter trial to determine whether prophylactic application of an emollient ointment would result in a lower incidence of death and/or NBS in the first 28 days of life, compared with routine skin care . METHODS: Infants of birth weight 501 to 1000 g and gestational age < or =30 weeks were assigned randomly to receive generalized application of ointment twice a day through day 14 (prophylactic group {P}) or local application of ointment to the site of injury (routine skin care {R}) . The study was conducted at 53 neonatal intensive care units that were members of the Vermont Oxford Network . RESULTS: Included in the analysis were 1191 infants (P: 602; R: 589) . No difference was found in the combined primary outcome of NBS or death (33.6% P vs 30.3% R; relative risk {RR}: 1.10; 95% confidence interval {CI}: 0.89, 1.27) . The incidence of death was no different between the groups (10.8% P vs 12.1% R; RR: 0.87; 95% CI: 0.59, 1.25) . More infants in the prophylactic group had NBS (25.8% P vs 20.4% R; RR: 1.26; 95% CI: 1.02, 1.54), predominantly in the lower birth weight infants (501-750 g) and for infections caused by coagulase-negative staphylococci . Infants in the prophylactic group had better skin condition on days 1 to 14 of life and less skin injury on days 15 to 28 of life . There was no difference between groups in other complications of prematurity . CONCLUSIONS: Prophylactic application of ointment did not lead to a difference in death and/or NBS in the first 28 days of life . There may be an increase in the risk of NBS associated with this practice.

Int J Antimicrob Agents, 2004 May, 23(5), 513 - 6
In vitro activity of mupirocin and amoxicillin-clavulanate alone and in combination against staphylococci including those resistant to methicillin; Alou L et al.; Mupirocin and amoxicillin-clavulanate were synergistic against 9 of 49 (18%) strains of methicillin-resistant and methicillin-susceptible Staphylococcus aureus and coagulase-negative staphylococci (CNS) . A pattern of enhanced killing was also found using time-kill studies . Time-kill assays were more discriminatory than chequerboard titration assays in demonstrating synergy . These results suggest that combinations of amoxicillin-clavulanate and mupirocin may have therapeutic benefits in prophylaxis against staphylococcal infections.

Lancet Infect Dis, 2004 May, 4(5), 278 - 86
Mucosa or skin as source of coagulase-negative staphylococcal bacteraemia?
Costa SF, Miceli MH, Anaissie EJ.
Nosocomial bacteraemia is associated with significant morbidity, mortality, and cost worldwide, and is most commonly caused by coagulase-negative staphylococci (CONS) . Establishing the source of CONS bacteraemia is therefore important in the prevention and management of this infection . CONS infections are presumed to originate at the cutaneous sites of central venous catheters (CVCs), a belief that has led to prevention strategies that focus almost exclusively on the skin . However, mucosal colonisation by CONS is well established, suggesting that mucosal sites might be an important source of CONS bacteraemia . We review the published material that evaluates the source(s) of CONS . We included only studies that used a strict definition of CONS bacteraemia, evaluated skin and other potential sources of CONS, and studied the molecular association between CONS blood isolates and their potential sources . Three published reports fulfilled our criteria . In cancer patients with CONS or CONS bacteraemia, most of the colonising strains that had a molecular match with the strain recovered from the blood of the same patient were mucosal isolates; by contrast, no association was seen between CONS blood and skin isolates . Furthermore, in several patient populations evidence was reported of mucosal colonisation by CONS and in several reports experimental and clinical mucosal translocation of CONS with subsequent bacteraemia was documented . Together these data indicate that mucosal sites are an important source of CONS bacteraemia . Clinical strategies for the treatment of patients with a positive blood culture for CONS, the widespread use of antimicrobial-coated CVCs, and maximum barrier protection for CVC insertion should be reassessed, and strategies to decrease mucosal colonisation by CONS should be developed.

Acta Vet Hung, 2004, 52(1), 7 - 17
Staphylococci isolated from animals and food with phenotypically reduced susceptibility to beta-lactamase-resistant beta-lactam antibiotics; Kaszanyitzky EJ et al.; The antibiotic resistance pattern of 1921 Staphylococcus strains isolated from animals and food within the last two years were examined using diffusion tests . Among them there were only 35 strains of S . aureus having an inhibition zone diameter of 15 mm or less, and 4 strains of coagulase-negative staphylococci (CNS) having a zone diameter of 18 mm or less to 1-microg oxacillin disk . These 39 strains were examined also by E-test to oxacillin and for the detection of the mecA gene by PCR in order to determine whether they might be real methicillin-resistant staphylococci . Among the 39 strains there were only two that were susceptible to penicillin by disk diffusion method; however, further examination by the penicillinase test showed that they produced beta-lactamase . While 19 (15 S . aureus, 4 CNS) strains were resistant and 7 strains were intermediate to oxacillin in disk diffusion test, the E-test gave 8 resistant and 5 intermediate results . Six out of the 8 oxacillin-resistant strains examined by disk diffusion and E-test harboured the mecA gene . Thus only 6 out of the examined 1921 strains proved to be mecA positive . These methicillin-resistant, mecA-positive strains (5 of the S . aureus strains and 1 of the S . epidermidis) originated from two dairy herds . The results prove that methicillin-resistant S . aureus (MRSA) strains in animals are really rare in Hungary . Eighteen strains were chosen and screened for minimal inhibitory concentration (MIC) of oxacillin with or without clavulanic acid or sulbactam, and three of them produced methicillinase enzyme.

Acta Neurochir (Wien), 2004 May, 146(5), 477 - 81 Epub 2004 Apr 08.
Cell index--a new parameter for the early diagnosis of ventriculostomy (external ventricular drainage)-related ventriculitis in patients with intraventricular hemorrhage?
Pfausler B, Beer R, Engelhardt K, Kemmler G, Mohsenipour I, Schmutzhard E.
Temporary intraventricular catheters for managing acute obstructive hydrocephalus caused by intraventricular haemorrhage carry a high risk of developing ventriculostomy-related ventriculitis (VRV) . The aim of this prospective study was to validate a new parameter for the early detection of an intraventricular infection . METHODS: Patients with external ventricular drainage due to intraventricular haemorrhage were enrolled in this prospective study . Leucocytes and erythrocytes in cerebrospinal fluid (CSF) and peripheral blood as well as bacteriological and chemical analysis of both were examined daily . The ratio of leucocytes to erythrocytes in CSF and leucocytes to erythrocytes in peripheral blood was calculated (so called cell index (CI)) and these values were compared with the "conventionally diagnosed" drain-associated ventriculitis . Furthermore, the CI values of the non-ventriculitis and ventriculitis group were compared using the t-test with adjustment for unequal variances (Welch test) . RESULTS: Thirteen patients with an external ventricular drainage (EVD) expected to be in place for more than seven days were enrolled . Seven patients developed a bacteriologically proven VRV (time 0) within 12 days (mean 8.57) . Diagnosis of VRV by CI was possible up to 3 days (mean 2.28) prior to conventional diagnosis . P values (Welch test) showed a significant difference on days -3 (P = 0.03), -2 (P = 0.03) and -1 (P = 0.012) - i.e . 3, 2 or 1 day, respectively, prior to the time point when the CSF culture grew staphylococci -, when compared with the mean cell indices of the controls, and a highly significant difference on time 0 (P < 0.001) . CONCLUSION: The calculated CI allows the diagnosis of nosocomial VRV in patients with intraventricular haemorrhage at a very early point of time .

J Biol Chem, 2004 Jul 23, 279(30), 31383 - 9 Epub 2004 Apr 26.
Crystal structures of Staphylococcus aureus sortase A and its substrate complex; Zong Y et al.; The cell wall envelope of staphylococci and other Gram-positive pathogens is coated with surface proteins that interact with human host tissues . Surface proteins of Staphylococcus aureus are covalently linked to the cell wall envelope by a mechanism requiring C-terminal sorting signals with an LPXTG motif . Sortase (SrtA) cleaves surface proteins between the threonine (T) and the glycine (G) of the LPXTG motif and catalyzes the formation of an amide bond between threonine at the C-terminal end of polypeptides and cell wall cross-bridges . The active site architecture and catalytic mechanism of sortase A has hitherto not been revealed . Here we present the crystal structures of native SrtA, of an active site mutant of SrtA, and of the mutant SrtA complexed with its substrate LPETG peptide and describe the substrate binding pocket of the enzyme . Highly conserved proline (P) and threonine (T) residues of the LPXTG motif are held in position by hydrophobic contacts, whereas the glutamic acid residue (E) at the X position points out into the solvent . The scissile T-G peptide bond is positioned between the active site Cys(184) and Arg(197) residues and at a greater distance from the imidazolium side chain of His(120) . All three residues, His(120), Cys(184), and Arg(197), are conserved in sortase enzymes from Gram-positive bacteria . Comparison of the active sites of S . aureus sortase A and sortase B provides insight into substrate specificity and suggests a universal sortase-catalyzed mechanism of bacterial surface protein anchoring in Gram-positive bacteria.

Clin Microbiol Infect, 2004 May, 10(5), 462 - 5
Comparison of PCR detection of mecA with agar dilution and Etest for oxacillin susceptibility testing in clinical isolates of coagulase-negative staphylococci; Tveten Y et al.; Oxacillin-resistant staphylococci are heterogeneous in their expression of resistance to beta-lactam antibiotics . Different recommendations regarding screening methods for routine use have been published . In this study, the susceptibility to oxacillin of 232 coagulase-negative staphylococci (CoNS) was determined by agar dilution, Etest and presence of the mecA gene . When an oxacillin resistance breakpoint of > or = 0.5 mg/L was used, the sensitivity and specificity for agar dilution were 97.6% and 100%, and those for Etest were 100% and 95.4% . The current National Committee for Clinical Laboratory Standards oxacillin breakpoint recommendation will categorise accurately the CoNS species encountered commonly.

Eur J Clin Microbiol Infect Dis, 2004 May, 23(5), 375 - 9 Epub 2004 Apr 27.
Relationship between glycopeptide use and decreased susceptibility to teicoplanin in isolates of coagulase-negative staphylococci; Bertin M et al.; To investigate the relationship between glycopeptide use and decreased susceptibility to teicoplanin in coagulase-negative staphylococci (CNS) isolates, data on teicoplanin susceptibility and glycopeptide use from existing microbiology laboratory and pharmacy databases were collected for the period between July 2000 and March 2001 . Pooled data for the entire study period were first used to analyse associations . Univariate analysis showed that the incidence of CNS with decreased susceptibility to teicoplanin was significantly correlated with the use of glycopetides, particularly with vancomycin use . This association was confirmed by multivariate analysis . This study suggests that variations in antimicrobial resistance are related to variations in antimicrobial use in the model of CNS with decreased susceptibility to teicoplanin, thus confirming the usefulness of restricting antimicrobial prescribing as a means of controlling resistance.

Eur J Clin Microbiol Infect Dis, 2004 May, 23(5), 396 - 8 Epub 2004 Apr 27.
Rapid diagnosis of Staphylococcus aureus bacteremia using S . aureus PNA FISH; Gonzalez V et al.; In the study presented here, the performance of the S . aureus PNA FISH assay was evaluated using 285 blood cultures (from 104 patients) that had gram-positive cocci resembling staphylococci on Gram stain . The new molecular test is based on a fluorescence in situ hybridization assay using peptide nucleic acid probes targeting Staphylococcus aureus 16S rRNA and is designed for the rapid identification of Staphylococcus aureus directly from positive blood cultures . The sensitivity, specificity, and positive and negative predictive values of the S . aureus PNA FISH for the rapid identification of Staphylococcus aureus directly from positive blood culture bottles were 100, 99.4, 99.2 and 100%, respectively.

Infect Dis Obstet Gynecol, 2003, 11(4), 221 - 6
Intrapartum antibiotic prophylaxis and early-onset neonatal sepsis patterns; Edwards RK et al.; OBJECTIVE: To compare the relative effects of intrapartum antibiotic prophylaxis regimens on patterns of early-onset neonatal sepsis . METHODS: We performed an historical cohort study of 17187 infants born at our center from September 1993 to February 2000 . A risk-based strategy was employed prior to July 1996 and a screening-based strategy was utilized thereafter . Ampicillin was utilized prior to March 1995 and penicillin was used thereafter . RESULTS: There were 75 cases of neonatal sepsis, 34 (4 . 10/1000) in the risk-based era and 41 (4.63/1000) in the screening-based era (p = 0.62) . There were fewer ampicillin-resistant isolates during the risk-based than the screening-based era (32 versus 61%; p = 0.014) . The only significant change in organism-specific sepsis rates was an increase in the rate of infection caused by coagulase-negative staphylococci in the screening-based era (0.36 versus 1.46/1000; p = 0.018), but 75% of infants infected with these organisms were not exposed to beta-lactam antibiotics within 72 h prior to delivery . For the risk- and screening-based eras, respectively, the rates of Gram-negative sepsis (1.21 versus 1.46/1000; p = 0.65) and the proportions of Gram-negative pathogens that were ampicillin-resistant (70 versus 77%; p = 1.0) were similar . The drug employed for prophylaxis did not appear to affect the pattern of sepsis cases . CONCLUSION: In our patient population, coagulase-negative staphylococci have become the most common cause of early-onset neonatal sepsis . The cause of this shift in pathogen prevalence is uncertain and seemingly unrelated to intrapartum antibiotic exposure.

Klin Med (Mosk), 2004, 82(2), 32 - 5
{Engagement of the lungs in infectious endocarditis}; Demin AA et al.; Clinical, biochemical, bacteriological, x-ray, electrocardiographic, ultrasonic and morphological examinations for pulmonary pathology were made in 230 patients with infectious endocarditis (IEC) treated in 1982-2001 . Pulmonary involvement was found in 30% of the examinees . Pulmonary onset of IEC caused misdiagnosis in 11% cases . Its appearance can be recognized by fever (100% cases), chest pain (73%), cough (50%) and dyspnea (46%) . Pulmonary affection and pulmonary onset of IEC were associated with disorders of the mitral (26 and 27%, respectively), aortic (17 and 8%, respectively), tricuspis (5 and 8%, respectively) valves or compound valvular heart disease (43 and 50%, respectively) . Bacterial vegetations of the heart valves were detected in 60% patients with pulmonary lesions and 62% patients with pulmonary onset of IEC in transthoracic ultrasonography . Pulmonary lesions and pulmonary onset of IEC were caused primarily by staphylococci (73 and 67%, respectively).

Antimicrob Agents Chemother, 2004 May, 48(5), 1823 - 36
Novel non-mecA-containing staphylococcal chromosomal cassette composite island containing pbp4 and tagF genes in a commensal staphylococcal species: a possible reservoir for antibiotic resistance islands in Staphylococcus aureus; Mongkolrattanothai K et al.; Among methicillin-resistant Staphylococcus aureus isolates, a staphylococcal chromosomal cassette containing the mecA gene (SCCmec) is integrated into the chromosome at a unique site . SCCmec also contains unique ccrAB recombinase genes mediating its integration and excision from the genome and is flanked by characteristic left and right direct- and inverted-repeat sequences . A few non-mecA-containing SCC elements that have the other molecular features described above have recently been described . The origin of these cassettes is not clear . We have identified two new members of the SCC family integrated within orfX in Staphylococcus epidermidis strain ATCC 12228, neither of which carries mecA . One is a 57-kb element flanked by a unique 28-bp SCC direct repeat . It was called the SCC composite island (SCC-CI) because it carries a 19-kb SCC element (SCCpbp4) nested within it . SCCpbp4 contains pbp4 and tagF genes, as well as one pair of ccrAB genes (allotype 2) flanked by classical SCC-specific terminal repeats . External to SCCpbp4, SCC-CI contains a second pair of ccrAB genes (allotype 4), three IS431 elements, and genes mediating resistance to heavy metals . Genes mediating restriction-modification that may facilitate horizontal transfer are also present within SCC-CI, both within and outside SCCpbp4 . Several novel arrangements of the SCC direct and inverted repeats were identified . Several long stretches of homology with other SCCs were found within and outside SCCpbp4 . In view of the fact that SCC-CI was found in a commensal species, it may represent a reservoir for sequences involved in genetic shuffling between staphylococci and may contribute to the diversity found in SCC elements.

Mol Microbiol, 2004 May, 52(3), 713 - 23
Staphylococcal NreB: an O(2)-sensing histidine protein kinase with an O(2)-labile iron-sulphur cluster of the FNR type; Kamps A et al.; The nreABC (nitrogen regulation) operon encodes a new staphylococcal two-component regulatory system that controls dissimilatory nitrate/nitrite reduction in response to oxygen . Unlike other two-component sensors NreB is a cytosolic protein with four N-terminal cysteine residues . It was shown that both the NreB-cysteine cluster and Fe ions are required for function . Isolated NreB was converted to the active form by incubation with cysteine desulphurase, ferrous ions and cysteine . This activation is typical for FeS-containing proteins and was reversed by oxygen . During reconstitution an absorption band at 420 nm and a yellow-brownish colour (typical for an FNR-type iron-sulphur cluster formation) developed . After alkylation of thiol groups in NreB and in the cysteine mutant NreB(C62S) almost no iron-sulphur cluster was incorporated; both findings corroborated the importance of the cysteine residues . Comparison of the kinase activity of (i) . the reconstituted (ii) . the unreconstituted, and (iii) . the unreconstituted and deferrated NreB-His indicated that NreB kinase activity depended on iron availability and was greatly enhanced by reconstitution . NreB is the first direct oxygen-sensing protein described in staphylococci so far . Reconstituted NreB contains 4-8 acid-labile Fe and sulphide ions per NreB which is in agreement with the presence of 1-2 iron-sulphur {4Fe-4S}(2+) clusters of the FNR-type . Unlike FNR, NreB does not act directly as transcriptional activator, but transfers the phosphoryl group to the response regulator NreC.

Drugs, 2004, 64(9), 913 - 36
Glycopeptide antibiotics: from conventional molecules to new derivatives; Van Bambeke F et al.; Vancomycin and teicoplanin are still the only glycopeptide antibiotics available for use in humans . Emergence of resistance in enterococci and staphylococci has led to restriction of their use to severe infections caused by Gram-positive bacteria for which no other alternative is acceptable (because of resistance or allergy) . In parallel, considerable efforts have been made to produce semisynthetic glycopeptides with improved pharmacokinetic and pharmacodynamic properties, and with activity towards resistant strains . Several molecules have now been obtained, helping to better delineate structure-activity relationships . Two are being currently evaluated for skin and soft tissue infections and are in phases II/III . The first, oritavancin (LY333328), is the 4'-chlorobiphenylmethyl derivative of chloroeremomycin, an analogue to vancomycin . It is characterised by: i) a spectrum covering vancomycin-resistant enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA) and to some extent glycopeptide-intermediate S . aureus (GISA); ii) rapid bactericidal activity including against the intracellular forms of enterococci and staphylococci; and iii) a prolonged half-life, allowing for daily administration . The second molecule is dalbavancin (BI397), a derivative of the teicoplanin analogue A40926 . Dalbavancin has a spectrum of activity similar to that of oritavancin against vancomycin-sensitive strains, but is not active against VRE . It can be administered once a week, based on its prolonged retention in the organism . Despite these remarkable properties, the use of these potent agents should be restricted to severe infections, as should the older glycopeptides, with an extension towards resistant or poorly sensitive bacteria, to limit the risk of potential selection of resistance.

J Bacteriol, 2004 May, 186(9), 2862 - 71
Genome of staphylococcal phage K: a new lineage of Myoviridae infecting gram-positive bacteria with a low G+C content; O'Flaherty S et al.; Phage K is a polyvalent phage of the Myoviridae family which is active against a wide range of staphylococci . Phage genome sequencing revealed a linear DNA genome of 127,395 bp, which carries 118 putative open reading frames . The genome is organized in a modular form, encoding modules for lysis, structural proteins, DNA replication, and transcription . Interestingly, the structural module shows high homology to the structural module from Listeria phage A511, suggesting intergenus horizontal transfer . In addition, phage K exhibits the potential to encode proteins necessary for its own replisome, including DNA ligase, primase, helicase, polymerase, RNase H, and DNA binding proteins . Phage K has a complete absence of GATC sites, making it insensitive to restriction enzymes which cleave this sequence . Three introns (lys-I1, pol-I2, and pol-I3) encoding putative endonucleases were located in the genome . Two of these (pol-I2 and pol-I3) were found to interrupt the DNA polymerase gene, while the other (lys-I1) interrupts the lysin gene . Two of the introns encode putative proteins with homology to HNH endonucleases, whereas the other encodes a 270-amino-acid protein which contains two zinc fingers (CX(2)CX(22)CX(2)C and CX(2)CX(23)CX(2)C) . The availability of the genome of this highly virulent phage, which is active against infective staphylococci, should provide new insights into the biology and evolution of large broad-spectrum polyvalent phages.

Oral Dis, 2004 May, 10(3), 155 - 62
Isolation and characterization of subgingival staphylococci from periodontitis patients and controls; Murdoch FE et al.; OBJECTIVES: To isolate and characterize subgingival staphylococci from patients with periodontal disease and from periodontally healthy controls, to evaluate the periodontal environment as a potential source for systemic staphylococcal infections . METHODS: Periopaper strips were used to isolate subgingival staphylococci from 28 patients with chronic periodontitis and 28 periodontally healthy age and sex-matched controls . Staphylococci were identified by microbiological methods and antibiotic resistance profiles determined . RESULTS: Staphylococci were isolated from 54% diseased subgingival and 43% healthy subgingival sites in over 50% periodontitis patients and from 29% healthy subgingival sites in 54% controls . No significant differences in the frequency of isolation or numbers of staphylococci isolated from diseased and healthy sites were noted . Staphylococcus epidermidis was the predominant oral species . Seventy per cent (115 of 165) of all isolates were penicillin-resistant . CONCLUSIONS: Subgingival staphylococci are present in both periodontitis patients and controls . In periodontitis there is an increased risk of bacteraemia because of the increased dentogingival surface area . The dental and periodontal health of patients at risk from haematogenous infections should therefore be maintained at a high level . Antibiotic resistance profiles of the oral staphylococcal isolates suggest that amoxicillin may no longer be a suitable antibiotic for prophylaxis against systemic infections such as prosthetic valve endocarditis.

J Chemother, 2004 Feb, 16(1), 3 - 12
Antimicrobial dihydrofolate reductase inhibitors--achievements and future options: review; Then RL; Despite all progress made in the fight against infections caused by bacteria, fungi, protozoa or viruses, there is a need for more and new active agents . Intensive efforts are currently directed against many new and attractive targets, and are hoped to result in new useful agents . The opportunities offered by some known and validated targets are, however, by far not exhausted . Dihydrofolate reductase (DHFR, EC 1.5.1.3) attracted much attention over several decades, which yielded several useful agents . There are excellent chances for new drugs in this field, and they are thought to increase by limiting the spectrum of activity . Whereas trimethoprim seems to present the optimum which can be achieved for a broad spectrum antibacterial agent, specific agents could probably be designed for well defined groups or specific organisms, such as staphylococci among the bacteria, or for a number of parasites, such as Plasmodium falciparum, the fungus Pneumocystis carinii, and several protozoa, such as Trypanosoma, Toxoplasma, and others . This would even extend to herbicides or specific plant pathogens . Achievements and current efforts directed against new DHFR-inhibitors are reviewed, considering only the most recent literature.

Am Heart J, 2004 Apr, 147(4), 587 - 92
Current and new antimicrobial agents; Eliopoulos GM; BACKGROUND: Infections may complicate cardiovascular surgery or may require surgery as an adjunct to successful treatment . Staphylococci, which are among the major pathogenic bacteria causing such infections, can be resistant to many of the older antibiotics . METHODS: The properties of several newer antimicrobial agents, recently approved or still investigational, were reviewed, with an emphasis on in vitro activities against staphylococci . RESULTS: The 2 approved agents, linezolid and quinupristin-dalfopristin, and several investigational agents being developed demonstrate in vitro antimicrobial activity against staphylococci . Three of these agents, daptomycin, which was approved by the US Food and Drug Administration in September 2003, and oritavancin and dalbavancin, which are in advanced stages of clinical development, are discussed . CONCLUSIONS: Although clinical studies are required, the in vitro anti-staphylococcal activities of several agents suggest that these antimicrobial agents might be useful options for some infections in patients who are intolerant of older antibiotics or who are infected with organisms that are resistant to older agents.

J Clin Microbiol, 2004 Apr, 42(4), 1800 - 2
Detection of inducible clindamycin resistance of staphylococci in conjunction with performance of automated broth susceptibility testing; Jorgensen JH et al.; This study has shown that inducible clindamycin resistance in staphylococci can be detected by disk testing on sheep blood agar inoculum purity plates used with the bioMerieux VITEK 2 . Tests of 150 erythromycin-resistant isolates correlated with standard D-zone tests on Mueller-Hinton agar and with PCR for erm(A), erm(C), and msr(A).

Diagn Microbiol Infect Dis, 2004 Apr, 48(4), 221 - 7
Identification of methicillin-resistant isolates of Staphylococcus aureus and coagulase-negative staphylococci responsible for bloodstream infections with the Phoenix system; Spanu T et al.; We evaluated the reliability of the new Phoenix system (Becton Dickinson Microbiology Systems, Sparks, Md.) in species-level identification and detection of oxacillin (methicillin) resistance among 493 staphylococcal isolates (Staphylococcus aureus, n = 223; coagulase-negative staphylococci, CoNS, n = 270) recovered from patients with bacteremia . Identification results were concordant with those of the ID 32 STAPH system (bioMerieux, Marcy l'Etoile, France) for 100% of S . aureus (223/223) and 97.4% (263/270) of CoNS isolates . For S . aureus isolates, Phoenix oxacillin-susceptibility results fully concurred with those of mecA polymerase chain reaction (PCR) (reference method): 96 mecA-positive isolates identified as resistant, 127 mecA-negative strains as susceptible . Two of the 210 mecA-positive CoNS isolates were misclassified as susceptible by the Phoenix (sensitivity 99%, positive predictive value 97.6%) . Five of 60 mecA-negative CoNS isolates were classified as resistant by the Phoenix (specificity 91.7%; negative predictive value 96.5%) . The Phoenix system can provide accurate and reliable identification of methicillin-resistant staphylococci responsible for bloodstream infections.

Roum Arch Microbiol Immunol, 2002 Oct-Dec, 61(4), 293 - 9
In vitro susceptibility of staphylococci to linezolid and other antimicrobial agents; Poiata A et al.; Linezolid is a member of the new class of antibacterial agents called oxazolidinones that are active against Gram positive organisms and exert their action by protein synthesis inhibition . In this study we investigated the in vitro activity of linezolid versus the other agent against clinical strains of staphylococci: Staphylococcus aureus (n = 82) and S . epidermidis (n = 32) collected in 2002 from hospitalized patients and healthy individuals, isolated from different biological samples . Agar dilution minimum inhibitory concentrations (MICs) were determined by using Mueller-Hinton agar according to the guidelines established by the National Committee for Clinical Laboratory Standards . Linezolid demonstrated excellent in vitro activity against all isolates tested, with MICs values in the range of susceptibility (< or = 8 microg/ml) . No associated resistance between linezolid and other agents tested was observed . The resistance among Gram positive bacteria continues to spread and for many patients infected with these resistant organisms antimicrobial therapy is ineffective and linezolid may be a new alternative treatment.

Mycoses, 2003, 46 Suppl 2, 21 - 32
{Antimicrobial prophylaxis and therapy in neutropenia}; Link H; Cytostatic chemotherapy of hematological malignancies if often complicated by neutropenia, which increases the risk of infections, especially if the neutrophil count is below 500/ml . Frequently, fever is the first and in most patients the only sign of an infection . Unexplained fever is defined as follows: temperature of > or = 38.3 degrees C or > or = 38.0 degrees C for at least one hour, or measured twice within 12 hours, if the neutrophil count is < 500/ml or < 1.000/ml with predicted decline to 500/ml . Different risk categories can be identified according to the duration of neutropenia: low risk < or = 5 days, intermediate risk 6-9 days, high risk > or = 10 days . An empirical mono- or duotherapy with antipseudomonal and antistreptococcal agents should be initiated immediately . In the low risk patient group, oral therapy with cipro-, levo-, or ofloxacin combined with amoxicillin/clavulanic acid is permissible . For standard and high risk patients, monotherapy can be carried out with either ceftazidime, cefepime, piperacillin with a beta-lactam-inhibitor or a carbapenem . In duo-therapy, a single dose of an aminoglycoside is combined with acylaminopenicillin or a cephalosporin of the third or fourth generation . The addition of glycopeptides in empirical therapy should only be considered in the presence of severe mucositis, or if a catheter-associated infection is suspected . If fever persists after 72-96 hours of first-line therapy with antibiotics, the regimen should be modified (with the exception of e.g . coagulase-negative staphylococci infections, because these infections take longer to respond) . Intermediate risk patients should additionally receive an aminoglycoside after monotherapy (penicillin or a cephalosporin) . If a carbepenem was administered for monotherapy, this can be followed by a quinolone and/or a glycopeptide . In the high risk group, the same modifications should be made as in the intermediate risk group but with additional systemic antifungal treatment . In the presence of unexplained fever, fluconazole can be administered at first, but if this fails, amphotericin B (conventional or liposomal), voriconazole, itraconazole or caspofungin should be started . After defervescence to < 38 degrees C, treatment should be continued for seven days if the neutrophil count is < 1.000/ml, and for two days if the neutrophil count is > 1.000/ml . In documented infections treatment is directed against the responsible pathogen, however maintaining the broad spectrum activity . Lung infiltrates are often caused by fungal organisms, therefore an empiric antifungal therapy is necessary which is active against Aspergillus species . Antibacterial prophylaxis can reduce the incidence of bacterial infections, but not the mortality by infections . If the risk of fungal infections exceeds 15%, an antifungal prophylaxis with resorbable drugs can be given.

Antimicrob Agents Chemother, 2004 Apr, 48(4), 1118 - 23
Efficacy of dalbavancin against methicillin-resistant Staphylococcus aureus in the rat granuloma pouch infection model; Jabes D et al.; Infections due to methicillin-resistant Staphylococcus aureus (MRSA) are an important cause of morbidity and mortality in hospital patients . Moreover, increased incidences of outpatient MRSA have been recently reported . This study investigated the bactericidal activity of dalbavancin, a novel, semisynthetic glycopeptide antibiotic, against methicillin-sensitive S . aureus (MSSA) and MRSA in the rat granuloma pouch infection model . A single intravenous dose of 10 mg of dalbavancin/kg of body weight reduced the viable MRSA count in pouch exudates by more than 2 log CFU/ml, and regrowth was prevented for up to 120 h . Comparable results with vancomycin required four 100-mg/kg intramuscular doses . With one or two doses of vancomycin, the bacterial load declined over proportionately shorter periods of time, followed by regrowth . Reduction of the bacterial load obtained with 100- and 200-mg/kg oral doses of linezolid was relatively transient, with regrowth starting at 48 h . A single 10-mg/kg dose of dalbavancin reduced the MSSA count at 24 h to below the limit of detection, with no regrowth for at least 96 h . Dalbavancin demonstrated good exudate penetration; the ratio of the area under the curve (AUC) in plasma to the AUC in pouch exudate was 1.01 . The in vivo activity of dalbavancin in this model is consistent with the antibiotic concentrations that are reached and maintained for extended periods of time after a single 10-mg/kg dose and with in vitro data showing that these concentrations are bactericidal for staphylococci . The pharmacokinetic and efficacy data seen in this relevant model of infection suggest that dalbavancin may be administered less frequently than vancomycin and linezolid.

J Bone Joint Surg Br, 2004 Mar, 86(2), 266 - 8
Infection in total joint replacements . Why we screen MRSA when MRSE is the problem?
Mohanty SS, Kay PR.
A retrospective review of MRSA screening showed that of a total of 8911 patients screened pre-operatively between May 1996 and February 2001, 83 (0.9%) had MRSA isolated from one source or another . During the same period, 115 (13.6%) of 844 positive tissue samples taken during surgery grew Staphylococcus aureus . Of these only 1 (0.01%) was reported to be methicillin-resistant (MRSA) . However, a total of 366 (43.4%) isolates from tissue samples were reported as coagulase-negative staphylococci (C-NS) . Of these, 312 samples were tested for methicillin sensitivity, of which 172 (55.1%) were found to be resistant . Staphylococcus epidermidis is the most prevalent and persistent species found on most skin and mucous membranes, constituting 65% to 90% of all staphylococci . Most isolates in tissue samples were found to be methicillin-resistant coagulase-negative staphylococcus (55.1%) . Hence, it may be appropriate to undertake screening for methicillin-resistant Staphylococcus epidermidis in addition to that for MRSA.

Syst Appl Microbiol, 2004 Mar, 27(2), 211 - 8
Molecular identification and differentiation of Staphylococcus species and strains of cheese origin; Hoppe-Seyler TS et al.; Amplified Ribosomal-DNA Restriction Analysis (ARDRA) was used to differentiate among 12 species and 4 subspecies of the genus Staphylococcus . With a universal primer pair a 2.4 kbp PCR-product was amplified, including the 16S rDNA, the 16S-23S rDNA interspacer region, and about 500 bp of the 23S rDNA . Species-specific restriction patterns were found using the restriction enzymes HindIII and XmnI separately . Cheese related staphylococci were clearly differentiated . ARDRA results were in good agreement with results of partial sequencing of the 16S rDNA . ARDRA could fully replace the biochemical identification with ID32 Staph (BioMerieux) which was less reliable when staphylococci of cheese origin were analysed . Genomic restriction digests of cheese-related S . equorum strains by SmaI and SacI gave unique strain-specific restriction patterns which can be used to identify starter staphylococci in a complex microbial environment such as the surface of Red-Smear cheeses.

Acta Paediatr, 2004 Feb, 93(2), 211 - 5
Coagulase-negative staphylococcal sepsis as a predictor of bronchopulmonary dysplasia; Liljedahl M et al.; AIM: To determine whether sepsis caused by coagulase-negative staphylococci (CoNS) is a risk factor for developing bronchopulmonary dysplasia (BPD) in premature newborns . METHODS: All newborns born at < or = 30 wk of gestation at Orebro University Hospital during 1994-2001 with clinical sepsis caused by CoNS (group A, n = 22) or by other bacteria (group B, n = 17) were included and compared with premature newborns without sepsis (group C, n = 53) . Clinical sepsis was defined as a positive blood culture (monoculture) plus clinical symptoms and laboratory findings . BPD was defined as treatment with oxygen > 21% for at least 28 d . RESULTS: The incidence of BPD differed between the three groups, as follows: CoNS sepsis (A) 64%, other sepsis (B) 41% and control (C) 24% . The difference between the control group and the sepsis groups was highly significant (p = 0.006) . In a univariate model the crude estimates of relative risk (RR) for occurrence of BPD increased with presence of sepsis and particularly with presence of sepsis with CoNS (A: RR 2.6, 95% CI 1.5-4.6, p = 0.001; B: RR 1.7, CI 0.8-3.5, p = 0.17) . When regression was performed with two additional predictive variables in multivariate models including sepsis, gestational age and mechanical ventilation (group A: RR 1.5, CI 1.1-2.0, p = 0.004; group B: RR 0.9, CI 0.6-1.4, p = 0.67), the estimates were lower . CONCLUSION: The relative risk for BPD is significantly increased in premature newborns with sepsis caused by CoNS compared with those with sepsis caused by other bacteria and compared with premature newborns with no sepsis.

Blood Purif, 2004, 22(2), 216 - 23
Intraperitoneal nitric oxide production in patients treated by continuous ambulatory peritonal dialysis; Davenport A et al.; BACKGROUND: Nitric oxide (NO) generation within the peritoneum could potentially affect peritoneal transport by increasing capillary vasodilatation, and increase peritoneal permeability during episodes of bacterial peritonitis . As peritoneal mesothelial cells have a common embryological derivation with endothelial cells, then mesothelial cells could potentially be a major source of locally produced NO . METHODS: NO was measured using the Griess reaction in fresh and spent dialysate effluent (SPDE) from uninfected CAPD patients, and from those during episodes of bacterial peritonitis . Human peritoneal mesothelial cells (HPMC) were cultured and NO production determined in the presence of SPDE and the effect of a potential NO substrate, L-arginine, and NO synthase inhibitor, L-NMMA . NO production by peritoneal macrophages (MO), obtained from SPDE and the effect of staphylococci was also determined . RNA for inducible nitric oxide synthase (iNOS) was sought using Northern blotting technique following combination stimulation with lipopolysaccharide and cytokines (IL-1beta, TNF-alpha and gamma-INF, and/or spent dialysate from patients with bacterial peritonitis) . RESULTS: Whereas fresh CAPD dialysate was nitrite-free, SPDE from the day time exchange contained 41 +/- 3 microM (nitrite and nitrate), and that from the overnight dwell 91 +/- 8 microM . During CAPD peritonitis, dialysate nitrite and nitrate increased from 9.3 +/-0.8 to 17.5 +/- 2.4 microM/l x h, for the first CAPD bag at presentation, and 15.2 +/- 1.8 for the second and 16.2 +/- 2.4 for the third exchange (p < 0.01 compared to non-infected control) . By the second day, levels had returned to baseline, 7.3 +/- 0.9 microM/l x h . HPMC produced 261 nmol nitrate and nitrite/mg cell protein, and this increased in a dose-dependent manner with the addition of spent uninfected CAPD dialysate, to 365 nmol/mg with 1:10 dilution and 655 nmol/mg with 1:2 dilution, p < 0.001 . The addition of the substrate, L-arginine, resulted in a 10% increase in nitrite and nitrate production, whereas the addition of L-NMMA produced a 10% reduction . Peritoneal MO obtained from SPDE produced similar quantities of nitrite and nitrate to peritoneal mesothelial cells, and cultures of Staphylococcus aureus resulted in a reduction in nitrite and nitrate levels, as they were used as a growth requirement . However, we could not demonstrate RNA production for iNOS by HPMC following cytokine or SPDE stimulation . CONCLUSIONS: This suggests that HPMC may be an important source of locally generated NO within the peritoneal cavity under basal conditions, but as they do not contain iNOS, the increased NO produced during episodes of acute bacterial peritonitis is more likely due to a combination of increased NO production by peritoneal endothelial cells and transmigrating macrophages .

Vaccine, 2004 Feb 17, 22(7), 872 - 9
Biologic properties and vaccine potential of the staphylococcal poly-N-acetyl glucosamine surface polysaccharide; Maira-Litran T et al.; Staphylococci have become the most common causes of nosocomial bacterial infections, and this fact, along with increasing problems associated with antimicrobial resistance, spurs the need for finding immunotherapeutic alternatives to prevent and possibly treat these infections . Most virulent, clinical isolates of both coagulase-negative staphylococci (CoNS) and Staphylococcus aureus carry the ica locus which encodes proteins that synthesize a polymer of beta-1-6 linked N-acetyl glucosamine residues (PNAG) . Animal studies have shown purified PNAG can elicit protective immunity against both CoNS and S . aureus, suggesting its potential as a broadly protective vaccine for many clinically important strains of staphylococci.

Am J Transplant, 2004 Apr, 4(4), 574 - 82
Infected bilomas in liver transplant recipients, incidence, risk factors and implications for prevention; Said A et al.; Bilomas, infected hepatic fluid collections, are a frequent complication of liver transplantation . We report a case-control cohort study to determine the incidence and microbiologic profile of bilomas and risk factors for biloma formation in 492 patients undergoing liver transplantation from 1994 to 2001 . Fifty-seven patients (11.5%) developed one or more bilomas; 95% in the first year post-transplantation . The most common initial infecting pathogens were enterococci (37%), one-half resistant to vancomycin (VRE); coagulase-negative staphylococci (26%); and Candida species (26%) . Infection by coagulase-negative staphylococci was strongly associated with the presence of a T-tube (OR 9.60, p=0.02) . In stepwise logistic regression multivariable analyses, hepatic artery thrombosis (OR 90.9, p<0.0001), hepatic artery stenosis (OR 13.2, p<0.0001) and Roux-en-Y choledochojejunostomy (OR 5.8, p=0.03) were independent risk factors for biloma formation; ursodeoxycholic acid use was highly protective (OR 0.1, p=0.002) . Strategies to prevent biloma formation must focus on measures to prevent hepatic artery thrombosis and colonization of liver transplant patients by multiresistant nosocomial pathogens . T-tube drainage post-transplantation bears reassessment . The protective effect of ursodeoxycholic acid found in this study warrants confirmation in a prospective multicenter, randomized trial.

Pediatr Infect Dis J, 2004 Mar, 23(3), 201 - 6
Vancomycin usage in central venous catheters in a neonatal intensive care unit; Elhassan NO et al.; BACKGROUND: We previously reported that vancomycin in hyperalimentation solution reduces catheter-related infections in the neonatal intensive care unit . Since June 1993 vancomycin (25 microg/ml) was routinely added to central venous catheter solutions, primarily hyperalimentation solution . Because the prophylactic use of vancomycin could lead to the emergence of resistant organisms, the decision to discontinue this practice was made in April of 1999 . The use of vancomycin was reserved for documented infections with vancomycin-susceptible organisms . OBJECTIVE: To compare catheter longevity, rate of laboratory-confirmed blood stream infections and total vancomycin exposure between two 18-month periods before and after the cessation of prophylactic vancomycin use . METHODS: Data were evaluated for every neonate in whom a percutaneous central venous catheter was placed . RESULTS: There were 394 neonates enrolled . No statistically significant difference was identified between the two periods regarding the mean catheter days or number of catheters per patient . There was a higher rate of Gram-negative laboratory-confirmed blood stream infections during Period I in patients with percutaneous central venous catheters in place . There were more isolates of coagulase-negative staphylococci in Period II, resulting in more frequent vancomycin therapy institution and thus an overall increase in the amount of vancomycin used in that period CONCLUSION: Discontinuing the use of prophylactic vancomycin resulted in exposure of fewer neonates to vancomycin but a higher total amount of vancomycin used . The impact of low dose widespread exposure to vancomycin vs . high dose limited exposure on the microbiologic flora in the neonatal intensive care unit should be further examined.

Int J Antimicrob Agents, 2004 Feb, 23(2), 113 - 9
Oxazolidinones: activity, mode of action, and mechanism of resistance; Bozdogan B et al.; Oxazolidinones are a new group of antibiotics . These synthetic drugs are active against a large spectrum of Gram-positive bacteria, including methicillin- and vancomycin-resistant staphylococci, vancomycin-resistant enterococci, penicillin-resistant pneumococci and anaerobes . Oxazolidinones inhibit protein synthesis by binding at the P site at the ribosomal 50S subunit . Resistance to other protein synthesis inhibitors does not affect oxazolidinone activity, however rare development of oxazolidinone resistance cases, associated with 23S rRNA alterations during treatment have been reported . Linezolid, the first oxazolidinone available, has already taken its place in the clinic for treatment of Gram-positive infections . Pharmacokinetic properties as well as its good penetration and accumulation in the tissue including bone, lung, vegetations, haematoma and cerebrospinal fluid, allow its use for surgical infections.

Rev Prat, 2003 Dec 15, 53(19), 2119 - 27
{Infections of intravascular perfusion sets}; Blot F; Catheter-related infections (CRI) are a leading cause of morbidity and sometimes a cause of death in cancer patients . For preventive strategies, intra- and extra-luminal colonization pathways should be taken into account . A definite diagnosis of CRI requires usually the removal of the catheter for culture of the catheter-tip . However, only about 20% of the catheters removed for suspicion of CRI actually prove infected . The diagnosis of CRI is likely when a bloodstream infection due to coagulase negative staphylococcus, S . aureus or Candida spp occurs, without other infectious focus . Among the catheter-tip culture techniques, quantitative methods offer the better sensitivity-specificity/complexity-cost compromise, and should be preferred to semi-quantitative ones . When a venous access port is removed because of suspected CRI, the catheter tip and the port itself should be both cultured . Immediate removal of the catheter and urgent antibiotic treatment are mandatory when severe local infection (such as tunnelitis or cellulitis) or severe sepsis occurs . Usually, a CRI due to S . aureus, Pseudomonas spp or Candida spp requires also the removal of the catheter . Diagnostic techniques without catheter removal may be only proposed when local or systemic severity signs are lacking . Recently, the measurement of the differential time to positivity between paired blood cultures drawn simultaneously on the catheter and on a peripheral vein has been proposed . Finally, the direct examination of blood drawn from the catheter using acridine-orange leucocyte cytospin test seems to be a promising and rapid method for the diagnosis of CRI . When a CRI is diagnosed, a treatment without catheter removal may be proposed when local or systemic severity signs are lacking mainly if coagulase negative staphylococci are involved; in such case, both systemic antibiotic therapy and lock-therapy should be associated . In case of clinical failure of this strategy after 48-72 hours, the catheter should be removed . If the sepsis persist, a residual infectious focus (thrombophlebitis, endocarditis, secondary localisation) should be investigated.

J Clin Microbiol, 2004 Mar, 42(3), 992 - 5
Molecular epidemiology of coagulase-negative staphylococci causing sepsis in a neonatal intensive care unit over an 11-year period; Krediet TG et al.; Coagulase-negative staphylococci (CoNS) are the major causative microorganisms in neonatal nosocomial sepsis . Previous studies have shown that CoNS sepsis in the neonatal intensive care unit (NICU) is caused by predominant molecular types that are widely distributed among both neonates and staff . Some of these molecular types may persist in the NICU for years . The purpose of the present study was to determine the dynamic behavior of CoNS strains causing sepsis over a prolonged period of time by determining the molecular types of all blood isolates from septicemic infants over a period of 11 years (1991 to 2001) . The results show that neonatal CoNS sepsis is increasingly caused by a few predominant molecular clusters . The most striking finding was that in recent years one molecular cluster emerged as the predominant cause of neonatal CoNS sepsis, responsible for no less than 31% (20 of 65) of blood isolates in 2001 . Antibiotic resistance, particularly beta-lactam resistance, is probably an important selective force considering the high mecA gene carriage of CoNS blood isolates (70 to 92%) . We conclude that neonatal CoNS sepsis is increasingly caused by a limited number of predominant molecular CoNS types and that antibiotic resistance is probably a major selective force.

Infez Med, 2003 Dec, 11(4), 183 - 8
{Non-tubercular vertebral osteomyelitis: diagnosis and therapy of 45 patients from a single Italian centre}; Carrega G et al.; AIM OF THE STUDY: to evaluate the episodes of non-tubercular spondylodiskitis diagnosed between 1998 and 2002 at the Ospedale S . Corona, Pietra Ligure (SV) . METHODS: perspective evaluation of vertebral osteomyelitis classified as spontaneous or iatrogenic if associated with procedures on the spinal cord, with detection of associated risk factors, localization, aetiology and treatment . RESULTS: 45 episodes, 71% spontaneous and 29% iatrogenic were observed . Associated risk factors were present in 47% of spontaneous spondylodiskitis . Lumbosacral localization was detected in 68% of spontaneous and 100% of iatrogenic episodes . Other localizations in spontaneous spondylodiskitis were dorsal (25%) or cervical (7%) . Methicillin-sensitive staphylococci caused the majority of spontaneous spondylodiskitis, while methicillin-resistant strains were more frequently involved in iatrogenic episodes . Among spontaneous spondylodiskitis, 63% healed with antibiotics for 8 weeks, but surgery was often needed in dorsal localizations . In iatrogenic forms antibacterial therapy for 8 weeks-6 months was effective in cases not associated with foreign bodies but their presence always required surgery for healing . CONCLUSIONS: spondylodiskitis is more frequently localized at lumbosacral level . Beta-lactams are generally effective in spontaneous episodes, while iatrogenic ones often require associations of drugs . Surgery may be required in the case of dorsal localization or in the presence of foreign bodies.

Infez Med, 2003 Sep, 11(3), 133 - 8
{Non-tubercular vertebral osteomyelitis: diagnosis and therapy of 45 patients from a single Italian centre}; Carrega G et al.; AIM OF THE STUDY: to evaluate the episodes of non-tubercular spondylodiskitis diagnosed between 1998 and 2002 at Ospedale S . Corona, Pietra Ligure (SV) . METHODS: prospective evaluation of vertebral osteomyelitis classified as spontaneous or iatrogenic if associated with procedures on the spinal cord, with detection of associated risk factors, localization, etiology and treatment . RESULTS: 45 episodes, 71% spontaneous and 29% iatrogenic were observed . Associated risk factors were present in 47% of spontaneous spondylodiskitis . Lumbosacral localization was detected in 68% of spontaneous and 100% of iatrogenic episodes . Other localizations in spontaneous spondylodiskitis were dorsal (25%) or cervical (7%) . Methicillin-sensitive staphylococci caused the majority of spontaneous spondylodiskitis, while methicillin-resistant strains were more frequently involved in iatrogenic episodes . Among spontaneous spondylodiskitis, 63% healed with antibiotics for 8 weeks, but surgery was often needed in dorsal localizations . In iatrogenic forms antibacterial therapy for 8 weeks-6 months was effective in cases not associated with foreign bodies but their presence always required surgery for healing . CONCLUSIONS: spondylodiskitis is more frequently localized at the lumbosacral level . Beta-lactams are generally effective in spontaneous episodes, while iatrogenic episodes often require associations of drugs . Surgery may be required in the case of dorsal localization or in the presence of foreign bodies.

Crit Care, 2004 Feb, 8(1), R42 - 7 Epub 2003 Dec 22.
Multiresistant coagulase-negative staphylococci disseminate frequently between intubated patients in a multidisciplinary intensive care unit; Agvald-Ohman C et al.; INTRODUCTION: The intensive care unit is burdened with a high frequency of nosocomial infections often caused by multiresistant nosocomial pathogens . Coagulase-negative staphylococci (CoNS) are reported to be the third causative agent of nosocomial infections and the most frequent cause of nosocomial bloodstream infections . CoNS are a part of the normal microflora of skin but can also colonize the nasal mucosa, the lower airways and invasive devices . The main aim of the present study was to investigate colonization and the rate of cross-transmissions of CoNS between intubated patients in a multidisciplinary intensive care unit . MATERIALS AND METHODS: Twenty consecutive patients, ventilated for at least 3 days, were included . Samples were collected from the upper and lower airways . All samples were cultured quantitatively and CoNS were identified by morphology and biochemical tests . A total of 199 CoNS isolates from 17 patients were genetically fingerprinted by pulsed-field gel electrophoresis in order to identify clones and to monitor dissemination within and between patients . RESULTS: An unexpected high number of transmission events were detected . Five genotypes were each isolated from two or more patients, and 14/20 patients were involved in at least one and up to eight probable transmission events . CONCLUSIONS: A frequent transmission of CoNS was found between patients in the intensive care unit . Although transmission of bacteria does not necessarily lead to infection, it is nevertheless an indication that infection control measures can be improved.

J Dairy Sci, 2004 Jan, 87(1), 46 - 52
Changes in milk composition as affected by subclinical mastitis in sheep; Leitner G et al.; The mechanism of the effects of glandular-level subclinical mastitis in dairy sheep on milk yield and on its composition as expressed in curd yield was studied . Thirty-six Israeli-Assaf dairy sheep with one udder half infected with identified coagulase-negative staphylococci and the contralateral gland free of bacteria were chosen . The milk yield of the infected halves was significantly lower than that of the uninfected ones (0.36 vs . 0.76 kg/milking) . The somatic cell count and N-acetyl-beta-D-glucosaminidase activity were significantly higher in the infected halves than in the uninfected ones . The plasminogen activator and plasmin (PL) activities were significantly higher in the infected glands than in the uninfected ones, whereas plasminogen (PLG) activity and the ratio PLG:PL were significantly lower in the infected glands . Concentrations of Ca2+ did not differ, whereas Ca2+ activity was significantly lower and proteose peptone concentration was 2.4 times as high in the infected glands than in the uninfected ones . Curd yield was significantly lower in the infected glands than in the uninfected ones.

J Antibiot (Tokyo), 2003 Nov, 56(11), 923 - 30
Acremonidins, new polyketide-derived antibiotics produced by Acremonium sp., LL-Cyan 416; He H et al.; Acremonidins A to approximately E (1 to approximately 5) were produced by fermentation of Acremonium sp., LL-Cyan 416, in heterogeneous phases . The structures of these compounds, containing a bridging keto group, were determined by spectroscopic analysis . Acremonidins A and B showed moderate activity against Gram-positive bacteria, including the methicillin-resistant staphylococci and vancomycin-resistant enterococci . Selective acylations of acremonidin B afforded ester derivatives 6 to approximately 9 that exhibited improved antibacterial activity.

Pathol Biol (Paris), 2004 Feb, 52(1), 26 - 32
{Accuracy of four agar diffusion methods and the Vitek 2 automated system for the detection of the methicillin resistance in coagulase negative staphylococci}; Aissa N et al.; AIM OF THE STUDY: Technical difficulties may occur in the detection of methicillin resistance in coagulase negative staphylococci . Phenotypic methods, such as disk diffusion testing, sometimes fail to detect methicillin resistance because of its poor expression . Four of these methods were compared with the VITEK 2 system . MATERIALS AND METHODS: The accuracy of the VITEK 2 system and the agar diffusion methods according to the current CASFM and NCCLS guidelines were assessed for methicillin susceptibility testing of 70 coagulase negative staphylococci isolates harboring the mecA gene for which the detection of the methicillin resistance was particularly difficult: the CASFM recommendations applied in 1998 failed to categorize them as methicillin-resistant . RESULTS: Among the different methods currently suggested by the CASFM, those using a heavy inoculum and a hypersaline medium give better results, but they remain however less efficient than the NCCLS recommendations testing (sensitivity: 71-86% vs . 94-94% respectively) . The VITEK 2 was more efficient (sensitivity: 91%) than the disk diffusion methods recommended by the CASFM and slightly less efficient than the method recommended by the NCCLS . CONCLUSION: The VITEK 2 automated system, compared with the disk diffusion methods, showed adequate accuracy for detection of oxacillin resistance in coagulase negative staphylococci.

FEMS Microbiol Lett, 2004 Jan 30, 230(2), 191 - 5
Susceptibility of methicillin-resistant staphylococci to oregano essential oil, carvacrol and thymol; Nostro A et al.; The aim of this study was to evaluate the susceptibility of methicillin-susceptible and methicillin-resistant staphylococci (MSS, MRS) to oregano essential oil, carvacrol and thymol . The commercial aerial parts of Origanum vulgare L . were hydrodistilled and the essential oil analysed by gas- chromatography/electron impact mass spectrometry . The inhibition efficacy of this essence and its major components was assayed against 26 MSS and 21 MRS, using an agar dilution method . The methicillin resistance was thoroughly typed by Epsilometer test (E-test), polymerase chain reaction for mecA gene detection and PBP2' latex agglutination test . The results clearly demonstrated that the comparison between the susceptibility of MSS and MRS to oregano oil, carvacrol and thymol showed no significant differences (Fisher's exact test, P > 0.05) . The best minimum inhibitory concentration values were reported for carvacrol (0.015-0.03%, v/v) followed by thymol (0.03-0.06%, v/v) and oregano oil (0.06-0.125%, v/v).

Am J Rhinol, 2003 Nov-Dec, 17(6), 321 - 6
A superantigen hypothesis for the pathogenesis of chronic hyperplastic sinusitis with massive nasal polyposis; Bernstein JM et al.; BACKGROUND: The pathogenesis of chronic hyperplastic sinusitis with massive nasal polyposis is still an enigma; however, the molecular biology of this disease is beginning to become unraveled and the proinflammatory cytokines and the message and the product of these cytokines have all been identified in nasal polyps . However, the initial trigger that causes inflammation of the lateral wall of the nose to up-regulate lymphocytes and eosinophils is still unknown . METHODS: Thirteen patients with massive polyposis were studied . The mucus of the nasal cavities surrounding the nasal polyps was studied for both bacterial and fungal species . The lymphocytes of the nasal polyps were extracted and evaluated for the T-cell receptor, particularly, the variable beta region of this receptor . Enterotoxins (superantigens) of the bacteria were studied . Finally, the histopathology of nasal polyps was studied . RESULTS: Fifty-five percent of the patients had toxin-producing Staphylococcus aureus in the nasal mucus adjacent to the polyps . Three different enterotoxins were isolated, including Staphylococcus enterotoxin A, Staphylococcus enterotoxin B, and toxic shock syndrome toxin 1 . The variable B specificity for these superantigens was identified also in the polyp lymphocyte T-cell receptor . CONCLUSION: A superantigen hypothesis for massive polyposis is suggested because the most common bacterial species found in the nasal mucus is Staphylococcus aureus . These bacteria produce enterotoxins in all of the cases studied and the corresponding variable beta region of the T-cell receptor also was up-regulated in the polyp lymphocytes in cases studied thus far . These data taken together suggest that the initial injury to the lateral wall of the nose may be the result of toxin-producing Staphylococci . Superantigens (enterotoxins) may up-regulate lymphocytes to produce cytokines that are responsible for the massive up-regulation of lymphocytes, eosinophils, and macrophages, the three most common inflammatory cells found in massive nasal polyposis.

Mikrobiyol Bul, 2003 Oct, 37(4), 235 - 40
{Sensitivity of methicillin resistant staphylococci to linezolid and some other antimicrobial agents}; Ertek M et al.; Linezolid is a synthetic antimicrobial agent which was introduced into clinical therapy in the early 2001 . It has an inhibitory effect against most of the Gram positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin resistant enterococci . In this study, in-vitro activities of linezolid, teicoplanin, vancomycin, ciprofloxacin, gentamicin, erythromycin, clindamycin, trimethoprim/sulfamethoxazole and rifampicin, were tested against 164 methicillin-resistant Staphylococcus spp . (96 S . aureus and 68 coagulase negative staphylococci) isolated from clinical specimens, by using disk diffusion method . None of the strains were found to be resistant to linezolid, vancomycin and teicoplanin . The resistance rates to other drugs were as follows; 80.5% to ciprofloxacin, 78.0% to gentamicin, 76.8% to erythromycin, 65.5% to clindamycin, 57.3% to trimethoprim/sulfamethoxazole and 41.5% to rifampicin . It was concluded that linezolid can be used as an alternative drug in severe infections caused by methicillin-resistant Staphylococcus spp., especially if the isolate was found to be resistant to teicoplanin or a side effect of vancomycin was observed.

J Clin Pathol, 2004 Feb, 57(2), 199 - 201
Rapid identification of Staphylococcus aureus from BacT/ALERT blood culture bottles by direct Gram stain characteristics; Murdoch DR et al.; The rapid identification of Staphylococcus aureus from positive blood cultures provides important clinical and therapeutic information . Using criteria based on direct Gram stain characteristics, an experienced microscopist was able to distinguish S aureus from other staphylococci isolated from BacT/ALERT blood culture bottles with an overall sensitivity of 89% and specificity of 98% . Furthermore, this method was readily taught to a clinical microbiologist who had not previously used the method first hand . Laboratories using the BacT/ALERT blood culture system should become familiar with these criteria so that S aureus bacteraemia can be identified rapidly.

Vet Microbiol, 2004 Jan 14, 98(1), 23 - 7
Transmission of multiple antimicrobial-resistant Staphylococcus intermedius between dogs affected by deep pyoderma and their owners; Guardabassi L et al.; The occurrence of antimicrobial-resistant Staphylococcus intermedius strains was investigated in 13 dogs affected by deep pyoderma, their owners and 13 individuals without daily contact with dogs (control group) . A total of 90 canine and 33 human S . intermedius isolates were typed by pulsed field gel electrophoresis (PFGE) to determine their possible identity . The occurrence of S . intermedius in dog-owners was significantly higher compared with the control group (Fisher's exact test, P=0.03), with S . intermedius being detected in seven dog-owners and in one individual not exposed to dogs . The results of the PFGE analysis showed that six out of 13 (46%) owners carried strains identical to those isolated from their dogs . Strains detected in both dogs and humans were resistant up to five different antimicrobial classes, including penicillins, fusidic acid, macrolides/lincosamides, tetracycline and chloramphenicol . Based on the results of this study, owners of dogs affected by deep pyoderma often carry multiple antimicrobial-resistant strains of S . intermedius occurring in their dogs . Independent of the direction and modalities of transmission, this finding raises questions concerning the possible transfer of resistance genes from canine S . intermedius to human pathogenic staphylococci.

Int J Antimicrob Agents, 2004 Jan, 23(1), 17 - 24
Comparison of daptomycin MIC results by DIN, NCCLS, SFM, and SRGA methods for 297 Gram-positive organisms; Koeth LM et al.; Daptomycin is a novel lipopeptide antibiotic with potent in vitro antibacterial activity against Gram-positive pathogens . For daptomycin minimal inhibitory concentration (MIC) testing, National Committee for Clinical Laboratory Standards (NCCLS) recommends the use of broth containing physiological levels of calcium (50 microg/ml) . The daptomycin susceptibility of 297 organisms was determined by NCCLS (Mueller-Hinton (MH) broth), Deutsches Institut fur Normung (DIN; isotonic broth), Societe Francaise de Microbiologie (SFM; three batches MH agar), and Swedish Reference Group for Antibiotics (SRGA; PDM agar) . All media were supplemented to 50 microg/ml Ca(2+) . There was good correlation between DIN and SFM methods (for staphylococci) with NCCLS results . Enterococci MICs using SFM methods were one to three dilutions lower and pneumococci results were one dilution higher than NCCLS . SRGA results were higher than NCCLS by one to four dilutions . Use of isotonic agar is an accepted alternative to isosensitest agar for the DIN method.

J Biol Chem, 2004 Apr 9, 279(15), 14665 - 72 Epub 2004 Jan 14.
Quorum sensing in Staphylococci is regulated via phosphorylation of three conserved histidine residues; Gov Y et al.; Staphylococcus aureus cause infections by producing toxins, a process regulated by cell-cell communication (quorum sensing) through the histidine-phosphorylation of the target of RNAIII-activating protein (TRAP) . We show here that TRAP is highly conserved in staphylococci and contains three completely conserved histidine residues (His-66, His-79, His-154) that are phosphorylated and essential for its activity . This was tested by constructing a TRAP(-) strain with each of the conserved histidine residues changed to alanine by site-directed mutagenesis . All mutants were tested for pathogenesis in vitro (expression of RNAIII and hemolytic activity) and in vivo (murine cellulitis model) . Results show that RNAIII is not expressed in the TRAP(-) strain, that it is non hemolytic, and that it does not cause disease in vivo . These pathogenic phenotypes could be rescued in the strain containing the recovered traP, confirming the importance of TRAP in S . aureus pathogenesis . The phosphorylation of TRAP mutated in any of the conserved histidine residues was significantly reduced, and mutants defective in any one of these residues were non-pathogenic in vitro or in vivo, whereas those mutated in a non-conserved histidine residue (His-124) were as pathogenic as the wild type . These results confirm the importance of the three conserved histidine residues in TRAP activity . The phosphorylation pattern, structure, and gene organization of TRAP deviates from signaling molecules known to date, suggesting that TRAP belongs to a novel class of signal transducers.

Antibiot Khimioter, 2003, 48(8), 11 - 6
{Linezolid for the treatment of nosocomial infections after cardiac surgery}; Beloborodova NV et al.; Clinical and bacteriological efficacy of linezolid in the treatment of cardiosurgical patients with various localization nosocomial infections due to problem grampositive cocci was estimated . The group included 10 patients: children at the age 3 months to 12 years (n = 3) and adults at the age of 17 to 65 years (n = 7) with infectious complications such as infectious endocarditis (n = 4), pneumonia (n = 2), wound infection (n = 3) and sepsis (n = 1) . All the patients isolated MR staphylococci . The use of glycopeptides was not possible in 6 patients because of vancomycin intolerance (n = 1), renal insufficiency (n = 1) and failure of the previous vancomycin therapy (n = 4) . To all the patients linezolid was administered per os (tablets or suspension) or intravenously (infusion solution) in doses of 600 mg twice a day (1200 mg a day) for the adults and 10 mg/kg body weight every 12 hours (20 mg/kg body weight a day) for the children . Linezolid monotherapy was applied to 2 patients . 8 patients were treated with linezolid in combination with some other antibiotics . By the clinical findings the positive dynamics confirmed by thermometry and hemograms was observed in 8 patients beginning from the 4th day of the linezolid use . Eradication of MR staphylococci from the blood, sputum and wounds was stated in all 10 patients . No toxic or adverse reactions were noted . It was concluded that linezolid is an optimal alternative to vancomycin especially when the use of the latter is not possible . No nephrotoxic effects of linezolid provided its recommendation as a drug of choice in the treatment of patients with renal disturbances, including polyorganic insufficiency.

Bull Soc Pathol Exot, 2003 Nov, 96(4), 283 - 5
{Profile and sensitivity to antibiotics of 115 staphylococcal strains implicated in septicemia in a Tunisian general hospital}; Boukadida J et al.; Staphylococci remain among the main responsible bacteria for septicemia . The resistance to antibiotics already makes a prognosis difficult . We carried out a study on Staphylococcus isolated from blood culture on 3 years in general hospital in Tunisia . We present the different species and their sensitivity to antibiotics . S . aureus is the predominant isolated species . S . epidermidis is essentially isolated in newborn intensive care unit . The meticillino-resistance concerns 14% of the whole strains and 5.2 of the S . aureus . No resistance is found as regard the vancomycin and the pristinamycin; ofloxacine is inactive on 14.8% of strains and the gentamicine on 11.3% . The resistance of staphylococci of our study is lower than the rates reported in southern Europe and in North America.

J Arthroplasty, 2004 Jan, 19(1), 78 - 87
Role of core biopsy in diagnosing infection before revision hip arthroplasty; Malhotra R et al.; A prerevision core biopsy from a failed hip joint was performed in 41 hips (38 patients) with a high index of suspicion for sepsis to determine its efficacy in diagnosing sepsis . Seven hips were known septic failures, and core biopsy was undertaken to confirm resolution of sepsis . Forty hips were revised, whereas 1 hip had excision of heterotopic bone . Cultures and permanent histologic sections were obtained during subsequent surgeries, and findings were compared with the results of core biopsy . The commonest organisms isolated were coagulase-negative staphylococci and Propionibacterium acne . In patients without a history of sepsis, core biopsy diagnosed infection with sensitivity of 80%, specificity of 100%, accuracy of 97%, and positive predictive value of 100% using histologic evidence of sepsis at revision as the standard . Core biopsy, however, had low sensitivity and accuracy in establishing resolution of infection in patients with a history of septic failure . Cultures from the aspirate had 44% sensitivity and positive predictive value of 57% . Core biopsy is useful for investigating failed arthroplasties with suspected sepsis . It has advantages of hip aspiration and allows examination of periprosthetic tissue histology . Its role in diagnosing resolution of infection in previously septic failures, however, is limited.

Clin Diagn Lab Immunol, 2004 Jan, 11(1), 203 - 10
Induction of nitric oxide production mediated by tumor necrosis factor alpha on staphylococcal enterotoxin C-stimulated bovine mammary gland cells; Komine K et al.; Mammary gland (MG) secretions (MGS) derived from secretory cows infected with coagulase-negative staphylococci (CoNS) showed somatic cell counts and lactoferrin similar to levels found in the MGS of secretory cows infected with Staphylococcus aureus . However, nitrite and nitrate (NOx) and staphylococcal enterotoxin C (SEC) were found in MGS infected with S . aureus at much higher levels than in cows infected with CoNS . These results suggested that NOx could be intimately correlated with the production of SEC in secretory cows infected with S . aureus . Therefore, we examined the production of NOx and the expression of proinflammatory cytokines and microsomal cytochrome P450 (CYP450) after injection of SEC into the MGS of secretory cows . We were able to detect NOx and the proinflammatory cytokine tumor necrosis factor alpha (TNF-alpha) on MG cells of SEC-injected MGS . It was also found that CYP450 in the MG cells from SEC-injected MGS was down-regulated by approximately one-third in comparison with the cells from phosphate-buffered saline-injected MGS . This in vitro system also showed that NOx could be induced in the culture of bovine macrophage-lined cells (FBM-17) with the supernatants of SEC-stimulated bovine peripheral blood lymphocytes (BoPBLs) but not in the culture of peripheral mononuclear cells with SEC-stimulated BoPBLs . The expression of the mRNA for both inducible nitric oxide synthase and TNF-alpha in FBM-17 was enhanced by culturing with the supernatant of SEC-stimulated BoPBLs, although CYP450 was down-regulated . These results indicate that the down-regulation of CYP450 was caused by the production of TNF-alpha in SEC-stimulating MG cells containing macrophages and via NOx production . Therefore, we suggest that NOx released from activated MG cells via the superantigenic activity of SEC caused oxidative damage to the MG in S . aureus-induced mastitis.

Infect Dis Clin North Am, 2003 Sep, 17(3), 479 - 501
Basic pharmacodynamics of antibacterials with clinical applications to the use of beta-lactams, glycopeptides, and linezolid; Craig WA; Time above MIC for free drug concentrations is the important PK-PD parameter correlating with the efficacy of beta-lactam antibiotics . The duration of time plasma concentrations needed to exceed the MIC is relatively similar for most organisms except staphylococci . Neutrophils contribute very little to the overall activity of beta-lactams . The appearance of increasing antimicrobial resistance can challenge the efficacy of these drugs when concentrations do not exceed the MIC for 40% to 50% of the dosing interval . Time above MIC with oral amoxicillin and amoxicillin-clavulanate can be enhanced with high-dose formulations . Time above MIC with parenteral preparations can be enhanced by longer intravenous infusions or even continuous infusion . The 24-hour AUC-MIC is probably the important PK-PD parameter correlating with the efficacy of vancomycin and teicoplanin . It clearly is the important parameter for the efficacy of linezolid . Usual doses of these drugs generally provide adequate plasma concentrations to treat effectively infections in which plasma concentrations are predictive of tissue concentrations . Penetration of these drugs into respiratory secretions, such as ELF, is enhanced for linezolid and reduced for vancomycin . This may give linezolid an advantage over vancomycin in certain respiratory infections.

Am J Phys Med Rehabil, 2004 Jan, 83(1), 75 - 8
Pertinacious habit on a rehabilitation unit: repetitive finger licking while paging through the clinical chart; LaBan MM et al.; A survey was performed to determine the frequency of unrecognized repetitive licking of fingers while reviewing hospital charts by various healthcare professionals who, by this habit, may be putting themselves at risk of acquiring a nosocomial infection . Nine of 14 charts demonstrated the presence of Staphylococci aureus, cultures obtained from three of nine charts grew methicillin-resistant S . aureus, and six grew methicillin-susceptible S . aureus . Of the 50 healthcare professionals surveyed, five (10%) admitted to habitual repetitive licking of fingers while reviewing charts . In addition, 30 (60%) of those surveyed had observed other professionals doing so . Forty-seven (94%) acknowledged that they did not routinely wash their hands after reviewing the charts, potentially placing themselves at risk of acquiring a nosocomial infection . As an immediate consequence of this study, staff members have been encouraged to wash their hands before and after reviewing a patient's chart.

Biol Pharm Bull, 2004 Jan, 27(1), 52 - 5
Effect of sodium diclofenac on serum and tissue concentration of amoxicillin and on staphylococcal infection; Groppo FC et al.; The effect of sodium diclofenac on serum and tissue amoxicillin concentration as well as their effect against staphylococcal infection was observed . Four polyurethane sponges were placed in the back of thirty rats . After 14 d, two granulomatous tissues received 0.5 ml of 10(8) cfu/ml (Staphylococcus aureus) . Two days later, the rats were divided into five groups: group 1 received amoxicillin 50 mg/kg/p.o., group 2 received amoxicillin 25 mg/kg/p.o., group 3 received sodium diclofenac 2.5 mg/kg/i.m . and amoxicillin 50 mg/kg/p.o., group 4 received sodium diclofenac 2.5 mg/kg/i.m., and group 5 (control group) received NaCl 1 ml/p.o . After six hours of drug administration, blood serum (10 microl) and noninfected granulomatous tissues were placed on Mueller-Hinton agar inoculated with 10(8) cfu/ml (S . aureus) . Infected tissues were dispersed in a sonic system and were spread (10 microl) on salt mannitol agar . Microorganisms were counted and the inhibition zones were measured after 18 h of incubation at 37 degrees C . Amoxicillin tissue concentration was 6.27 microg/g for group 1, 2.18 microg/g for group 2, and 0.72 microg/g for group 3 . The serum concentrations were 11.56 microg/ml for group 1, 5.36 microg/ml for group 2, and 1.34 microg/ml for group 3 . No differences were observed among group 1, 2, and 3 regarding staphylococci counts (Kruskall-Wallis test p>0.05) . Group 4 reduced (p<0.05) staphylococci counts comparing to group 5 . It was concluded that sodium diclofenac reduced serum and tissue amoxicillin concentration and, even in large doses, amoxicillin was not effective in eradicating the staphylococcal infection after 6 h of administration.

Ann Intern Med, 2004 Jan 6, 140(1), 18 - 25
Differential time to positivity: a useful method for diagnosing catheter-related bloodstream infections; Raad I et al.; BACKGROUND: Catheter-related bloodstream infections are associated with recognized morbidity and mortality, especially in critically ill patients . Accurate diagnosis of such infections results in proper management of patients and in reducing unnecessary removal of catheters . OBJECTIVE: To evaluate differential time to positivity as a method for diagnosing catheter-related bacteremias caused by both short-term and long-term use of central venous catheters . DESIGN: Prospective study design . SETTING: M.D . Anderson Cancer Center, Houston, Texas, a tertiary care cancer center . PATIENTS: All patients, between September 1999 and November 2000, who had the same organism isolated from blood cultures drawn simultaneously through the central venous catheter and the peripheral vein . MEASUREMENTS: Time necessary for the blood cultures from the central venous catheter and the peripheral vein to become positive, as well as other relevant patient information . RESULTS: 191 bloodstream infections with positive simultaneous central venous catheter and peripheral vein blood cultures were included . One hundred eight patients had catheter-related bacteremias, and 83 had non-catheter-related bacteremias . Catheter-related bacteremias were more frequently caused by staphylococci and less likely to be associated with underlying hematologic malignant conditions, neutropenia, and longer duration of hospitalization . As a diagnostic tool for catheter-related bacteremia (using a composite definition reference standard according to the Infectious Diseases Society of America guidelines), differential time to positivity of 120 minutes or more was associated with 81% sensitivity and 92% specificity for short-term catheters and 93% sensitivity and 75% specificity for long-term catheters . CONCLUSION: Differential time to positivity of 120 minutes or more is highly sensitive and specific for catheter-related bacteremia in patients who have short- and long-term catheters.

Am J Perinatol, 2003 Nov, 20(8), 491 - 501
Diagnostic value of cytokines and C-reactive protein in the first 24 hours of neonatal sepsis; Laborada G et al.; The first objective of this article was to determine the diagnostic accuracy of tumor necrosis factor-alpha, interleukin-6 (IL-6), and interleukin-8 (IL-8) in differentiating infected from noninfected neonates during the first 24 hours of suspected sepsis and to compare them to the currently used laboratory parameters: C-reactive protein (CRP), immature-to-total neutrophil ratio, and leukocyte and platelet count . The secondary objective was to compare the cytokine levels in subpopulations of neonates . Seventy-five premature and 30 term infants were enrolled . Blood samples for the "currently used laboratory tests" and the cytokine levels were obtained at the first suspicion of sepsis ("0-hour") and 18 to 30 hours later ("24-hours") . Patients were classified as septic (48) or nonseptic (57) . Thirty-two septic patients had positive blood cultures and 16 showed clinical signs of sepsis . Twenty septic patients had early-onset and 28 had late-onset sepsis . Sensitivity, specificity, and positive and negative predictive values (PPV and NPV) were calculated for each test . Receiver-operating characteristic curves were analyzed to determine the optimal thresholds . A combination of CRP > 10 pg/mL plus IL-6 > 18 pg/mL (sensitivity = 89%, specificity = 73%, PPV = 70%, NPV = 90%) was the best "0-hour" test, and CRP (sensitivity = 78%, specificity = 94%) was the best "24-hours" test . Lower IL-6 at 0-hour (p = 0.018) and IL-8 at 24 hours (p = 0.023) were detected among the patients infected with coagulase-negative staphylococci then with other bacteria . In conclusion, a combination of CRP + IL-6 provided additional diagnostic accuracy for differentiation between septic and nonseptic patients during the first 24 hours of suspected sepsis.

Can Vet J, 2003 Dec, 44(12), 978 - 81
{Evolution of bacterial resistance to certain antibacterial agents in horses in a veterinary hospital}; Peyrou M et al.; Evolution of bacterial resistance to certain antibacterial agents in horses in a veterinary hospital . A total of 255 antibiograms, conducted according to the Kirby-Bauer method from bacterial isolates collected from horses at the Hopital Veterinaire d'Enseignement at the Universite de Montreal between 1996 and 1998 were compared with the results obtained about 10 years ago with corresponding bacterial species . A significant increase in the percentage of strains resistant to trimethoprim-sulfamethoxazole (TMP-SXT), penicilline, tetracycline, and to gentamicin was observed . The percentages of isolates of Actinobacillus spp . and coagulase-positive staphylococci resistant to TMP-SXT increased from 0% to 17% and from 0% to 33%, respectively, (P < 0.05) . The percentage of isolates of Actinobacillus spp resistant to penicilline also increased from 33% to 73% (P < 0.05) . Regular monitoring of the evolution of bacterial resistance to antibacterial agents is indispensable in a hospital structure . The adoption of "good antibiotherapy practices" is essential to guarantee a decrease in the risks of selection and dissemination of a resistant bacterial strain.

Antimicrob Agents Chemother, 2004 Jan, 48(1), 285 - 96
Local variants of Staphylococcal cassette chromosome mec in sporadic methicillin-resistant Staphylococcus aureus and methicillin-resistant coagulase-negative Staphylococci: evidence of horizontal gene transfer?
Hanssen AM, Kjeldsen G, Sollid JU.
The mecA gene in Staphylococcus aureus is located on the genetic element staphylococcal cassette chromosome (SCC) . Different SCCmecs have been classified according to their putative recombinase genes (ccrA and ccrB) and overall genetic composition . Clinical isolates of coagulase-negative staphylococci (CoNS; n = 39) and S . aureus (n = 20) from Norway, India, Italy, Finland, the United States, and the United Kingdom were analyzed by pulsed-field gel electrophoresis, which showed that most isolates were genetically unrelated . Cluster analyses of 16S rRNA gene and pta sequences confirmed the traditional biochemical species identification . The mecI, mecR1, mecA, and ccrAB genes were detected by PCRs, identifying 19 out of 20 S . aureus and 17 out of 39 CoNS isolates as carriers of one of the three published ccrAB pairs . New variants of SCCmec were identified, as well as CoNS isolates containing ccrAB genes without the mec locus . ccrAB and mec PCRs were verified by hybridization . Sequence alignments of ccrAB genes showed a high level of diversity between the ccrAB alleles from different isolates, i.e., 94 to 100% and 95 to 100% homology for ccrAB1 and ccrAB2, respectively . All of the ccrAB3 genes identified were identical . Genetically unique and sporadic methicillin-resistant S . aureus (MRSA) contained local variants of ccrAB gene pairs identical to those found in MR-CoNS but different from those in MRSA from other regions . Allelic variants of ccrAB in isolates from the same geographic region showed sequence conservation independent of species . The species-independent sequence conservation found suggests that there is a closer genetic relationship between ccrAB2 in Norwegian staphylococci than between ccrAB2 sequences in international MRSA and Norwegian MRSA . This might indicate that different staphylococcal species acquire these genes locally by horizontal gene transfer.

Infect Immun, 2004 Jan, 72(1), 29 - 37
Role of siderophore biosynthesis in virulence of Staphylococcus aureus: identification and characterization of genes involved in production of a siderophore; Dale SE et al.; Molecular determinants underlying the production of siderophores in the human and animal pathogen Staphylococcus aureus and the contribution of siderophore production to the virulence of this bacterium have, until now, remained undefined . Here, we show that S . aureus strains RN6390 and Newman produce siderophore when the cells are starved for iron . We further identified and characterized a nine-gene, iron-regulated operon, designated sbn and situated between sirABC and galE on the S . aureus chromosome, that is involved in the production of a siderophore . Mutation of the sbnE gene, in both RN6390 and Newman, eliminates the ability of these strains to produce a siderophore under iron-limited growth conditions, while introduction of multicopy sbnE into sbnE mutants complemented the inability of the mutants to produce the siderophore . sbnE mutants, in both the RN6390 and Newman backgrounds, displayed a drastic growth deficiency, compared to the wild type, in iron-restricted growth medium, whereas no such deficiency was observed during growth in iron-replete medium . Complemented mutants showed a restored ability to grow under iron restriction . We further showed that an sbnE mutant was compromised in a murine kidney abscess model of S . aureus infection, illustrating the importance of siderophore production to the pathogenicity of S . aureus . sbn genes were present in all S . aureus strains tested (and all S . aureus genome sequences) but were undetectable in any of the 13 coagulase-negative staphylococci tested, including Staphylococcus epidermidis.

Bioorg Med Chem Lett, 2004 Jan 5, 14(1), 279 - 82
Mannopeptimycin esters and carbonates, potent antibiotic agents against drug-resistant bacteria; He H et al.; A series of ester and carbonate derivatives of the glycopeptide mannopeptimycin alpha (1) with potent activity against G+ bacteria, including the methicillin-resistant staphylococci and vancomycin-resistant enterococci, was synthesized . The SAR data obtained from natural and semisynthetic compounds demonstrated the importance of a hydrophobic group in the terminal mannosyl moiety for antibacterial activity.

Acta Vet Hung, 2003, 51(4), 451 - 64
Antibiotic resistance of staphylococci from humans, food and different animal species according to data of the Hungarian resistance monitoring system in 2001; Kaszanyitzky EJ et al.; Based on data of the Hungarian resistance monitoring system the antibiotic resistance of Staphylococcus strains of human and animal origin was studied . No methicillin-resistant staphylococci harbouring mecA gene were isolated from animals in 2001 . Penicillin resistance, mediated by penicillinase production, was the most frequent among Staphylococcus aureus strains isolated from humans (96%), from bovine mastitis (55%), from foods (45%) and from dogs . In staphylococci isolated from animals low resistance percentages to aminoglycosides (0-2%), fluoroquinolones (0.5-3%) and sulphonamides (0.5-4%) were found but in strains isolated humans these figures were higher (1-14%, 5-18% and 3-31%, respectively) . The most frequent antibiotic resistance profiles of strains isolated from animals and food were penicillin/tetracycline, penicillin/lincomycin and penicillin/lincomycin/tetracycline . Penicillin/tetracycline resistance was exhibited by strains from mastitis (3), samples from the meat industry (31), poultry flocks (1), poultry industry (1), noodle (1) and horses (2) . Penicillin/lincomycin resistance was found in 10 Staphylococcus strains from mastitis, 1 from the dairy industry, 1 from the meat industry and 6 from dogs . Isolates from mastitis (2), from the dairy industry (2), from pigs (1), from the meat industry (1) and from poultry (1) harboured penicillin/lincomycin/tetracycline resistance pattern . Multiresistant strains were usually isolated only from one and sometimes from two animal species; therefore, the spread of defined resistant strains (clones) among different animal species could not be demonstrated . These results also suggest that the transfer of antibiotic resistance of S . aureus from animals to humans probably occurs less frequently than is generally assumed.

Clin Infect Dis, 2004 Jan 1, 38(1), 92 - 8 Epub 2003 Dec 05.
Quinupristin-dalfopristin resistance in gram-positive bacteria: mechanism of resistance and epidemiology; Hershberger E et al.; Antimicrobial resistance in gram-positive bacteria is a continuing problem resulting in significant morbidity, mortality, and cost . Because of this resistance, new antimicrobial agents have been needed . Quinupristin-dalfopristin is a recently approved agent for treatment of these infections . Shortly after its introduction into clinical medicine, resistance was reported . Resistance can occur by one or more of several mechanisms, including enzymatic modification, active transport of efflux mediated by an adenosine triphosphate-binding protein, and alteration of the target site . Resistance is rare in isolates of staphylococci and Enterococcus faecium from humans . Resistance is common in isolates recovered from food animals and is related to the use of virginiamicin as a feed additive . Considering the effect antimicrobial resistance has on human health, as well as its economic impact, measures to preserve the usefulness of these agents and delay the development of resistance are urgently needed.

Thorac Cardiovasc Surg, 2003 Dec, 51(6), 338 - 41
Treatment of post-pneumonic empyema thoracis; Athanassiadi K et al.; OBJECTIVE: The present study evaluates the management of 65 consecutive patients with post-pneumonic empyema thoracis (PET) treated in our department during the last ten years . MATERIALS: There were 51 male (78.5 %) and 14 female (21.5 %) aged 23 - 82 years . The initial cause of PET was pneumonia (postoperative and posttraumatic empyemas were excluded) . In 2 cases, a bronchopleural fistula coexisted . Diagnosis was based on clinical, radiological and pleural fluid culture findings . Pneumonococci and staphylococci were the predominant bacterial isolates in our series . RESULTS: Tube thoracostomy drainage (TS) was performed in all our patients . Forty-nine patients (75.4 %) were successfully treated with TS alone . The other 16 patients were submitted to thoracotomy: lung decortication (n = 14) along with segmentectomy in two cases and the Eloesser procedure, also in two cases . The mortality rate reached 9.2 % (n = 6) . Septic shock, multiple organ failure, cardiac insufficiency, and end-stage renal failure were the causes . CONCLUSIONS: 1 . Complete drainage and full lung expansion by tube thoracostomy with suction are essential in the management of post-pneumonic empyema thoracis . Surgery should only be carried out right away if these conditions are not achieved . 2 . Despite clinical experience and the major strategies and procedures available, the mortality remains high.

J Med Microbiol, 2004 Jan, 53(Pt 1), 67 - 72
Coagulase-negative staphylococci: clinical, microbiological and molecular features to predict true bacteraemia; Garcia P et al.; Coagulase-negative staphylococci (CNS) are frequently isolated from blood cultures, where they may be only a contaminant or the cause of bacteraemia . Determining whether an isolate of CNS represents a true CNS bacteraemia is difficult, and there is no single criterion with sufficient specificity . The aim of this study was to assess those clinical, microbiological, pathogenic and genotypic features that characterize true CNS bacteraemia . Twenty patients having two or more blood cultures positive for CNS and 20 patients with only one positive blood culture were studied . Significant bacteraemia was defined according to clinical and laboratory criteria . Incubation time for blood cultures to become positive, macroscopic appearance of colonies, species determination, biotype, susceptibility to antimicrobials, PFGE pattern and adherence capacity were all studied . Clinical bacteraemia was present in 16/20 patients with two or more positive blood cultures and in 2/20 patients with only one positive blood culture . A significant difference was seen in the median time to positivity between the 18 clinical bacteraemias and 22 contaminations (23.6 versus 29.2 h; P = 0.04, Wilcoxon) . There was also a significant difference between the two groups in the median absorbance of the slime test (1.36 versus 0.58; P = 0.005) . All significant bacteraemias with two or more positive blood cultures had the same species identified, the same antimicrobial susceptibility pattern and the same PFGE pattern . In two patients with true bacteraemia with only one positive blood culture, the incubation time for the culture to turn positive was <24 h and the slime production absorbance was >2.5 . The most useful parameters for the diagnosis of true CNS bacteraemia for patients with two positive blood cultures were incubation time until positive, species identification, antimicrobial susceptibility pattern, slime production and PFGE pattern . For patients with only one blood culture positive for CNS, the useful parameters for prediction of true bacteraemia were incubation time until positive and slime production, both of which are simple, low-cost tests.

J Med Microbiol, 2004 Jan, 53(Pt 1), 51 - 5
Isolation and molecular characterization of multiresistant Staphylococcus sciuri and Staphylococcus haemolyticus associated with skin and soft-tissue infections; Shittu A et al.; The isolation, molecular identification and genotyping of multiresistant Staphylococcus sciuri and Staphylococcus haemolyticus from skin and soft-tissue infections are reported . Accurate and full identification of three coagulase-negative staphylococcal isolates was achieved using PCR, while the API STAPH method failed to identify an isolate of S . haemolyticus fully . The PCR assay, which detects polymorphism in the 16S-23S rRNA spacer region, is shown to be potentially useful for rapid and accurate identification of coagulase-negative staphylococci . Identical PFGE type and antibiotic-resistance profiles of two methicillin-resistant S . haemolyticus isolates in this study suggest the existence of a multiresistant community clone.

J Clin Microbiol, 2003 Dec, 41(12), 5695 - 8
Evaluation of S . aureus ID, a new chromogenic agar medium for detection of Staphylococcus aureus; Perry JD et al.; S . aureus ID (bioMerieux, La Balme Les Grottes, France) is a new chromogenic agar medium designed to enable the isolation of staphylococci and the specific identification of Staphylococcus aureus . S . aureus produces green colonies on this medium due to production of alpha-glucosidase . To evaluate this medium, a total of 350 wound swabs were cultured onto S . aureus ID, CHROMagar Staph . aureus, and conventional media routinely used in our laboratory . After 18 to 20 h of incubation, 96.8% of strains formed green colonies on S . aureus ID compared with 91.1% of strains forming mauve colonies on CHROMagar Staph . aureus . A total of 94.3% of strains were recovered within 18 to 20 h with conventional media . The sensitivity was increased after 48 h of incubation to 98.7, 96.2, and 95.6% with S . aureus ID, CHROMagar Staph . aureus, and conventional media, respectively . A total of 97.4% of green colonies on S . aureus ID were confirmed as S . aureus compared with 94.4% of mauve colonies on CHROMagar Staph . aureus . We conclude that S . aureus ID is a highly sensitive and specific medium for the isolation and identification of S . aureus from wound swabs.

J Antimicrob Chemother, 2004 Jan, 53(1), 105 - 8 Epub 2003 Dec 04.
Clonal dissemination of mupirocin-resistant staphylococci in Greek hospitals; Petinaki E et al.; OBJECTIVES: To determine the rates of mupirocin resistance in staphylococci during a 4 year period (1999-2002) in Greece . MATERIALS: A total of 1200 Staphylococcus aureus and 2760 coagulase-negative staphylococci (CoNS), consecutively collected from four Greek hospitals located in different geographical areas, were tested for susceptibility to mupirocin using the Etest and a reference agar dilution method . RESULTS: Twenty-four S . aureus (2%) and 532 CoNS (19.2%) were found to be mupirocin-resistant during the study period . High-level mupirocin resistance was detected in 20 S . aureus (1.6%) and in 440 CoNS (15.9%), respectively . No variations in the rates of mupirocin-resistant S . aureus in relation to the year of collection were observed . In contrast, the rate of mupirocin-resistant CoNS increased dramatically from 9% in 1999, to 14% in 2000, 20% in 2001 and reached 33% in 2002 . PFGE analysis revealed the presence of one main clone (A) among mupirocin-resistant S . aureus and two main clones (i and a) among Staphylococcus epidermidis isolates . CONCLUSIONS: In Greece, the rate of mupirocin-resistant S . aureus has remained low and steady since 1999 . The high rate of mupirocin-resistant CoNS (33%) in 2002 was due mainly to clonal dissemination of epidemic hospital clones.

J Pediatr (Rio J), 2002 Jul-Aug, 78(4), 279 - 88
{Clinical significance of coagulase-negative staphylococci isolated from neonates}; Cunha Mde L et al.; OBJECTIVE: To evaluate the clinical significance of coagulase-negative staphylococci (CNS) isolated from newborns' infections at Neonatal Unit of Hospital das Clinicas da Faculdade de Medicina de Botucatu . METHODS: The CNS strains isolated were identified and classified as clinically significant and contaminant, based on a series of clinical and laboratory data obtained from patients who stayed in the Neonatal Unit . The following data were analyzed: risk factors for infections, clinical evolution, abnormal blood cell counts and/or C-reactive protein and antibiotic therapy . RESULTS: Among the 117 CNS strains isolated, 60 (51.3%) were classified as significant and 57 (48.7%) as contaminant . Among the 54 infants infected by CNS, 43 (79.6%) presented very low birthweight (<1,500 g) . Most of the infants infected by CNS were submitted to two or more invasive procedures (77.8%), including use of catheter (88.9%), parenteral nutrition (64.8%) and mechanical ventilation (61.1%) . Staphylococcus epidermidis was the most frequently isolated species (77.8%) and more often associated with infection (86.7%) than with contamination (68.4%) . Other species of CNS, including two strains of S . haemolyticus, three strains of S . lugdunensis, one strain of S . simulans, one strain of S . warneri and one strain of S . xylosus were also isolated from infants with clinical evidence of pneumonia, necrotizing enterocolitis and sepsis . CONCLUSIONS: Most newborns infected by CNS presented important risk factors for infection onset, including birthweight <1,500 g, foreign body presence and previous use of antibiotics . The identification of CNS species constitutes a useful marker of infection, since S . epidermidis was the species more frequently associated with infection.

Intensive Care Med, 2004 Jan, 30(1), 62 - 7 Epub 2003 Nov 26.
The pathogenesis of catheter-related bloodstream infection with noncuffed short-term central venous catheters; Safdar N et al.; OBJECTIVE: Short-term, noncuffed, percutaneously inserted central venous catheters (CVCs) are widely used and cause more than 250,000 bloodstream infections (BSIs) in hospitals each year in the United States . We report a prospective study undertaken to determine the pathogenesis of CVC-related BSI . DESIGN AND SETTING: Prospective cohort study in a university hospital 24-bed medical-surgical intensive care unit . PATIENTS AND PARTICIPANTS: Patients participating in two randomized trials during 1998-2000-one studying the efficacy of a 1% chlorhexidine-75% alcohol solution for cutaneous antisepsis and the other a novel chlorhexidine-impregnated sponge dressing-formed the study population; CVC-related BSIs were considered to be extraluminally acquired if concordance was identified solely between isolates from catheter segments, skin, and blood cultures and intraluminally acquired if concordance was demonstrated only between hub or infusate and blood culture isolates, as confirmed by DNA subtyping of isolates from blood and catheter sites or infusate . RESULTS: Of 1,263 catheters (6075 CVC days) prospectively studied, 35 (2.7%) caused BSI (5.9 per 1000 CVC days); 27 were caused by coagulase-negative staphylococci . Overall, 45% of infections were extraluminally acquired, 26% were intraluminally derived, and the mechanism of infection was indeterminate in 29% . In the pooled control groups of the two trials, 25 CVC-related BSIs occurred (7.0 per 1000 CVC days), of which 60% of infections were extraluminally acquired, 12% were intraluminally derived and 28% were indeterminate . In contrast, CVC-related BSIs in the treatment groups were most often intraluminally derived (60%, p=0.006) . CONCLUSIONS: Most catheter-related BSIs with short-term percutaneously inserted, noncuffed CVCs were extraluminally acquired and derived from the cutaneous microflora . Strategies achieving successful suppression of cutaneous colonization can substantially reduce the risk of catheter-related BSI with short-term CVCs.

Biol Neonate, 2004, 85(3), 151 - 4 Epub 2003 Nov 25.
Translocation of coagulase-negative bacterial staphylococci in rats following intestinal ischemia-reperfusion injury; Luo CC et al.; Many patients with sepsis have bacteremia for which no septic focus is identified either clinically or by autopsy . This study was designed to determine the relationship between the ischemia-reperfusion injury (IRI) and bacterial translocation that might be involved in the pathogenesis of necrotizing enterocolitis . In the first experiment, a total of 32 Sprague-Dawley rats weighing 150-200 g were divided into four groups . The mesentery to isolated loop was occluded for 30, 60, and 90 min following 30-min reperfusion in the three groups of experimental animals with a micro-bulldog clamp . A control group involved the same technique and exposure, without occlusion of the mesentery . Two sets of blood culture were taken through a catheter in the portal vein immediately and 15 min after the reperfusion, respectively . In another experiment, bacteria isolated were fed in different doses to control rats and those after 30- or 60-min ischemia and 30-min reperfusion . Two sets of blood culture were taken following the procedure . Invasion and transcytosis of the bacteria through epithelial cells were studied in vitro using a Madin-Derby canine kidney (MDCK) cell monolayer model . PCR for delta toxin gene was performed on all bacteria isolated, using Staphylococcus epidermidis as the control . Coagulase-negative staphylococci (CoNS) were invariably isolated from mice with prolonged ischemia (90 min) and reperfusion . When bacteria were fed into mice with only 30-min ischemia, an inoculum as low as 5 x 10(5) CFU/ml could induce bacteremia . No bacterial translocation was found in control mice even fed with a higher dose of bacteria (5 x 10(8) CFU/ml) . In vitro experiments showed that CoNS failed to transcytose MDCK monolayer . These isolates were not cytotoxic to MDCK cells and contained no delta toxin gene . Bacterial translocation of CoNS occurred following severe bowel ischemia and reperfusion injury . Intact mucosa integrity readily prevented bacterial translocation; however, bacterial translocation could occur in rats following mild IRI in the presence of a higher number of CoNS in the gut .

Antimicrob Agents Chemother, 2003 Dec, 47(12), 3964 - 6
Linezolid penetration into bone and joint tissues infected with methicillin-resistant staphylococci; Kutscha-Lissberg F et al.; Penetration of linezolid into bone and joint tissues was studied by high-performance liquid chromatography in 13 patients suffering from implant-associated infections with methicillin-resistant staphylococci . Mean concentrations of linezolid in infected tissues were greater than 10 mg/liter in a sampling time range of 35 to 124 min after administration of the preoperative dose, except in bone specimens, where they reached 3.9 +/- 2.0 mg/liter.

Microb Drug Resist, 2003, 9 Suppl 1, S9 - 16
Linkage of erm(B) and aadE-sat4-aphA-3 in multiple-resistant Enterococcus faecium isolates of different ecological origins; Werner G et al.; Enterococcus faecium shares its antibiotic resistance gene pool with various Gram-positive bacteria . A gene cluster aadE-sat4-aphA-3, which was first described in staphylococci, has been recently identified also in E . faecium . In staphylococci, this gene cluster was mostly integrated into the transposable element, Tn5405 . We identified five different cluster types of Tn5405-like elements that were linked to erm(B) in 47 of 67 aadE-sat4-aphA-3 and erm(B) positive isolates (70.1%) . Clusters differed by insertion of additional DNA between the IS1182 transposase gene and the left inverted repeat of IS1182, an integration of IS1216 between erm(B) and ORF X deleting IS1182 and the 5' end of ORF X, or a loss of the left end of Tn5405 including IS1182, ORF X, and the 5' end of ORF Y . Twenty isolates (29.8%) possessed neither a link between erm(B) and aadE-sat4-aphA-3 nor an arrangement of aadE-sat4-aphA-3 in a Tn5405-like element . A 17-kb composite cluster was identified in a single hospital isolate linking determinants for glycopeptide (vanA), macrolide-lincosamide-streptogramin B {erm(B)}, and aminoglycoside-streptothricin (aadE-sat4-aphA-3) resistances.

Microb Drug Resist, 2003, 9 Suppl 1, S1 - 7
Analysis of genomic diversity and evolution of the low-level antiseptic resistance gene smr in Staphylococcus aureus; Alam MM et al.; A multidrug efflux pump specified by the smr gene mediates low-level antiseptic resistance in staphylococci . We analyzed the genomic diversity of smr and its gene cassette, a structural unit containing smr and terminal direct repeats (DRs), in 22 clinical strains of Staphylococcus aureus isolated over 9 years in a Japanese hospital . Although open reading frames (ORFs) of all the smr genes examined were identical to those reported previously (e.g., qacD in pSK41), smr gene cassettes were classified into three groups (types 1, 2, and 3) . The type 1 cassette had an identical genetic organization to that found in the plasmid pSK41, a putative prototype of the smr gene cassette, which contains DRs flanking smr . In the type 2 cassette, the rep gene and a putative replication nick site were found upstream of smr, between a SSOA (single-strand origin) sequence and DR1c, which are components of the type 1 cassette DR . In the type 3 cassette detected in a single strain, IS431 was located between the 3' end of smr and DR . It was suggested by genomic comparison that type 2 and type 3 cassettes might have been derived from the type 1 cassette via insertion of foreign DNA sequence, and that the type 2 cassette might be a precursor form of some previously reported smr cassettes, such as those in pSK108 and pNVH99 . Although MICs of antiseptics and ethidium bromide were generally the same among strains having type 1, 2, or 3 smr gene cassette, the type 1 cassette was detected most frequently . Moreover, the copy number of the smr gene in the type 2 cassette was found to be much higher than that in the type 1 or type 3 cassette.

J Vet Med B Infect Dis Vet Public Health, 2003 Nov, 50(9), 443 - 6
Tetracycline resistance in staphylococci from free-living rodents and insectivores; Hauschild T et al.; One hundred and fifty-eight staphylococcal strains isolated from wild rodents and insectivores were analysed for plasmid-borne resistance to tetracycline (Tc) . Only 10 isolates, six Staphylococcus saprophyticus isolates and single isolates of S . xylosus, S . equorum, S . warneri and S . cohnii subsp . cohnii carried a Tc resistance plasmid of approximately 4.4 kb as confirmed by protoplast transformation . All 10 plasmids harboured a Tc resistance gene of hybridization class K {tet(K)} as confirmed by polymerase chain reaction (PCR) . The plasmid was assigned to the pT181 family as it revealed a high degree of restriction map homology to pT181 and other members of this family . Macrorestriction analysis with the enzyme SmaI showed that three of the six isolates identified as S . saprophyticus shared the same pulsed-field gel electrophoresis (PFGE) pattern.

J Appl Microbiol, 2003, 95(5), 974 - 81
Staphylococcal accessory gene regulator (sar) as a signature gene to detect enterotoxigenic staphylococci; Padmapriya BP et al.; AIMS: To evaluate the use of a staphylococcal accessory gene regulator (sar) as a means of detecting enterotoxigenic staphylococci . METHODS AND RESULTS: SarA gene-specific primers were designed and applied in PCR, which resulted in the detection of 49 sar-positive isolates from a total of 67 natural food isolates of staphylococci . Colony hybridization using PCR-generated Digoxigenin (DIG)-labelled sarA probe tested in spiked samples of khoa (a traditional heat-concentrated milk product) comprising a mixed microflora ensured the specificity of the probe . Validation experiments with the commercial samples of khoa also demonstrated the specificity of the probe . PCR characterization for enterotoxins A-D revealed the presence of at least one of the toxin-encoding genes in all the sarA-positive isolates tested . CONCLUSION: The study indicated that sarA gene could be an ideal marker gene either in colony hybridization or in PCR, for an effective detection of potentially enterotoxigenic strains of staphylococci in a food system . SIGNIFICANCE AND IMPACT OF THE STUDY: As an alternative to targeting the individual toxin genes, a regulatory gene responsible for controlling the synthesis of various virulence factors may be a suitable target gene for screening potentially toxigenic staphylococci in food system using nucleic acid-based methods.

Acta Paediatr, 2003 Oct, 92(10), 1180 - 2
Microbiological factors associated with neonatal necrotizing enterocolitis: protective effect of early antibiotic treatment; Krediet TG et al.; AIM: The incidence of necrotizing enterocolitis (NEC) strongly increased in an neonatal intensive care unit (NICU) in 1997 and 1998 compared with previous years, which coincided with increased incidence of nosocomial sepsis . Specific risk factors related to this NICU and a possible relationship between NEC and nosocomial sepsis were studied retrospectively, including all patients with NEC since 1990 and matched controls . METHODS: Clinical and bacteriological data from the period before the development of NEC and a similar period for the controls were collected retrospectively and corrected for birthweight and gestational age . Statistical analysis was performed by a stepwise regression model . RESULTS: Data of 104 neonates with NEC and matched controls were analysed . The median day of onset of NEC was 12 d (range 1-63 d) . Significant risk factors for NEC were: insertion of a peripheral artery catheter {odds ratio (OR) 2.3, 95% confidence interval (95% CI) 1.3-3.9} and a central venous catheter (OR 5.6, 95% CI 3.1-10.1), colonization with Klebsiella sp . (OR 3.4, 95% CI 1.5-7.5) and Escherichia coli (OR 2.1, 95% CI 1.0-4.5), and the occurrence of sepsis, in particular due to coagulase-negative staphylococci (OR 2.6, 95% CI 1.4-5.1) . The risk for NEC was decreased after the early use (< 48 h after birth) of amoxicillin-clavulanate and gentamicin (OR 0.3, 95% CI 0.2-0.6) . CONCLUSION: Insertion of central venous and peripheral arterial catheters is positively associated with NEC, as is colonization with the Gram-negative bacilli Klebsiella and E . coli and the occurrence of sepsis, particularly due to coagulase-negative staphylococci . Early treatment with amoxicillin-clavulanate and gentamicin is negatively associated with NEC and may be protective against NEC.

J Antibiot (Tokyo), 2003 Sep, 56(9), 773 - 82
Production and characterization of monochlorinated and dechlorinated A40926 derivatives; Beltrametti F et al.; Nonomuraea sp . ATCC 39727 is the producer of the A40926 complex of lipoglycopeptide antibiotics which contain chlorine atoms in amino acids 3 and 6 of the peptide backbone . Using a classical mutagenesis and selection approach we have isolated a Nonomuraea sp . ATCC 39727 mutant strain able to direct production towards new A40926 analogues dechloro-A40926 (DDC) lacking two chlorine atoms and the two monochloro-A40926 (MDC1 and MDC2) that are not produced fermenting the wild type strain . Dechlorinated A40926 derivatives were obtained in considerable amount in a standard fermentation process and were purified and chemically characterized . The dechlorinated A40926 derivatives DDC and MDC2 showed improved antimicrobial activity against coagulase negative staphylococci strains in respect to A40926 complex . Dechlorinated derivatives of the related antibiotic teicoplanin are also reported in the literature and are generally less active than the parental products.

J Food Prot, 2003 Nov, 66(11), 2151 - 5
Comparison of the Baird-Parker agar and 3M Petrifilm Staph Express Count plate methods for enumeration of Staphylococcus aureus in naturally and artificially contaminated foods; Ingham SC et al.; The recently developed 3M Petrifilm Staph Express Count plate (PFSE) method was compared with the U.S . Food and Drug Administration Bacteriological Analytical Manual's Baird-Parker agar spread plate (B-P) method for enumeration of Staphylococcus aureus in naturally contaminated, mechanically separated poultry (MSP; n = 92) and raw milk (n = 12) . In addition, mozzarella and Parmesan cheeses and hot-smoked rainbow trout and chub were surface inoculated with a three-strain mixture of S . aureus, stored at 5 degrees C, and periodically analyzed with both methods for numbers of S . aureus . For naturally contaminated raw milk and MSP samples, the PFSE method yielded counts that were not significantly different (P > 0.05) from counts obtained using the B-P method . From raw milk and MSP samples, 60% (21 of 35) and 55% (124 of 226), respectively, of confirmed (DNAse-positive) isolates from PFSE plates were identified by further testing as S . aureus . Corresponding S . aureus identification rates for isolates forming typical colonies on B-P plates were 53% (19 of 36) and 50% (125 of 248) . For both methods, other staphylococci composed the vast majority of tested isolates that were not identified as S . aureus . For inoculated hot-smoked fish, S . aureus counts from the PFSE method were not significantly different from counts from the B-P method . Compared to the B-P method, significantly lower numbers of inoculated S . aureus were recovered using the PFSE method in analyses of mozzarella cheese stored 28 and 42 days at 4 degrees C . The PFSE and B-P methods were not significantly different for inoculated cheeses at all other sampling times . DNAse-positive isolates from PFSE analyses of inoculated cheeses and smoked fish were identified as S . aureus 98% (51 of 52) and 86% (36 of 42) of the time, respectively, as compared with 100% (58 of 58) and 95% (40 of 42) of the time for typical B-P isolates . Overall, the PFSE and B-P methods appeared to perform similarly in enumeration of S . aureus in animal-derived foods.

Scand J Infect Dis, 2003, 35(9), 677 - 82
Impact of antibiotic resistance on the treatment of sepsis; Turnidge J; Antibiotics are essential to the treatment of bacterial sepsis as they reduce the bacterial burden . The impact of bacterial resistance has recently been studied and found to be important in a range of conditions . Resistance to antibiotics can be defined genotypically, phenotypically and clinically through pharmacokinetic/pharmacodynamic studies and their correlations with clinical outcomes . Although the kinetics of antibiotics has been shown to be favourably altered in sepsis, a range of studies in sepsis has revealed that for most pathogens resistance contributes to significant increases in mortality . This has been clearly demonstrated in bacteraemia, including community- and hospital-acquired infection, and with bacteraemia caused by vancomycin-resistant enterococci, methicillin-resistant staphylococci and extended-spectrum producing Gram-negative bacteria . Significant mortality increases have also been seen with ventilator-associated pneumonia and serious infections requiring admission to intensive care . Gentotypic and phenotypic resistance in coagulase-negative staphylococci causing bacteraemia, and in invasive pneumococcal disease has not shown differences in mortality . In the latter case, dosage regimens have to date been adequate to overcome laboratory-defined resistance . Early indications are that de-escalating therapy from broad-spectrum initial coverage after results of cultures and susceptibility tests become available does not jeopardize outcomes, and further prospective studies are warranted . There is now convincing evidence that broad-spectrum initial therapy to cover the likely pathogens and their resistances pending culture results is mandatory in sepsis to minimize adverse outcomes.

J Pept Sci, 2003 Oct, 9(10), 612 - 9
Turning virulence on and off in staphylococci; Muir TW; The progress made in a multidisciplinary research programme designed to elucidate the molecular basis of the interaction of Staphylococcus aureus secreted autoinducing peptides (AIPs) with their respective cell surface receptors is reviewed.

Sichuan Da Xue Xue Bao Yi Xue Ban, 2003 Oct, 34(4), 663 - 6
{Combination PCR of mecA, femA genes for detection of MRSA}; Chen Z et al.; OBJECTIVE: To make a comparison of PCR assay, Agar Dilution and Disk Diffusion as for detecting Staphylococcal mecA, femA genes . METHODS: A total of 178 strains of Staphylococci were isolated from three large scale hospitals in Chengdu . Disk Diffusion and staphylococcal mecA, femA gene PCR assay for detecting MRSA were compared with Agar Dilution . RESULTS: The sensitivity and specificity of Disk Diffusion for detecting MRSA were 94.4% and 92.4% respectively . The sensitivity and specificity of Disk Diffusion for detecting MRCNS were 89.5% and 73.7% respectively . Compared with Agar Dilution, Staphylococcus aureus mecA gene PCR assay's sensitivity and specificity were 91.7% and 95.5% respectively . In all the 178 strains of Staphylococci, mecA gene combining with femA gene PCR assay's specificity was up to 97.9% . CONCLUSION: The detection of femA gene together with mecA gene by PCR is not only an approach for differentiating MRSA from MRCNS, but also a rapid, highly specific method which can be used as an auxiliary method in clinical microbiological laboratory.

Clin Microbiol Infect, 2003 Nov, 9(11), 1139 - 41
Staphylococcus lugdunensis vertebral osteomyelitis; Greig JM et al.; We report a case of vertebral osteomyelitis due to the coagulase-negative staphylococcus, Staphylococcus lugdunensis . This is only the second such case reported in the literature in an immunocompetent host . When the patient's lumbar spine inflammatory mass was drained, the coagulase-negative staphylococcus obtained was discarded as a likely contaminant . We discuss the situation when coagulase-negative staphylococci require further identification and look at the unique features of S . lugdunensis . Isolation of S . lugdunensis is usually significant, and the organism should not be discarded as a contaminant without careful consideration.

Pediatr Infect Dis J, 2003 Nov, 22(11), 968 - 74
Use of incubation time to detection in BACTEC 9240 to distinguish coagulase-negative staphylococcal contamination from infection in pediatric blood cultures; Haimi-Cohen Y et al.; BACKGROUND: Growth of coagulase-negative staphylococci (CoNS) in a blood culture indicates infection or contamination . Differentiation may be difficult in pediatric patients from whom only a single blood culture is commonly obtained . METHODS: We evaluated the use of the incubation time to detection of growth {time to positive (TTP)} of CoNS in a continuously monitored blood culture system (BACTEC Peds/F bottles in BACTEC 9240) to differentiate infection from contamination . Three groups of febrile pediatric patients with blood cultures growing CoNS were identified: Group 1, children with vascular catheter-associated bloodstream infection; Group 2, previously healthy children with a contaminant; Group 3, chronically ill children with a contaminant . RESULTS: The median TTP for blood cultures from the 17 infection episodes, 11 h {mean, 13.2 h; 95% confidence interval (CI), 11.4 to 17.7}, was significantly shorter than either the 30 episodes in the previously healthy group with contaminant, median 19 h (mean, 22.7 h; 95% CI 19.5 to 26.2; P < 0.0001) or the 12 episodes in the chronically ill group with contaminant, median 24 h (mean, 35.2 h; 95% CI 17.2 to 53.1; P < 0.0001) . A TTP of < or =15 h had a positive predictive value of 84% for diagnosis of infection . A TTP of > or =22 h had a positive predictive value of 87% for diagnosis of contaminant . CONCLUSION: In our experience the TTP was a useful adjunctive test to determine the clinical significance of isolation of CoNS from a blood culture from a pediatric patient.

J Manag Care Pharm, 2003 Jul-Aug, 9(4), 317 - 26
Early switch and early discharge opportunities in intravenous vancomycin treatment of suspected methicillin-resistant staphylococcal species infections; Parodi S et al.; BACKGROUND: Patients with methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant coagulase negative staphylococci (MR-CoNS) infections are usually treated with intravenous (IV) vancomycin and remain hospitalized for the duration of IV therapy . Oral linezolid has excellent bioavailability and activity against MRSA and MR-CoNS and offers the potential for outpatient treatment of MRSA and MR-CoNS infections . OBJECTIVE: To determine the potential for early switch (ES) from IV vancomycin to oral linezolid and subsequent early discharge (ED) in hospitalized, adult patients treated for an MRSA or MR-CoNS infection . METHODS: We conducted a retrospective cohort study at the Veterans Administration Greater Los Angeles Healthcare System from January 1 through December 31, 2000 . Potential reductions in vancomycin use, hospital length of stay (LOS), and economic savings were determined . RESULTS: A total of 103 of 177 (58%) treatment courses for MRSA or MR-CoNS infections were potentially eligible for ES, with annual and mean decreases in vancomycin use of 535 defined daily doses and 5.2 days per event . Of the ES cohort, 55 of 103 (53%) courses were potentially eligible for ED, with an annual and mean reduction in LOS of 181 days and 3.3 days per event . The total potential savings was $220,181, at an average of $3,478 per event . CONCLUSION: Early switch to oral linezolid for treatment of MRSA or MR-CoNS infections could reduce vancomycin use, hospital length of stay, and economic costs . KEYWORDS: Oxazolidanone, Vancomycin, Length of stay, Methicillin resistance, Staphylococcal infections

Ann Fr Anesth Reanim, 2003 Nov, 22(9), 773 - 7
{Infectious complications related to non-tunneled central venous catheters in immunocompromised patients: prospective study about 210 cases}; Abdelkefi A et al.; OBJECTIVE: To evaluate infectious complications related to non-tunneled central venous catheter in immunocompromised patients, in a bone marrow unit . METHODS: From July to April 2002, we inserted 210 non-tunneled central venous catheters in 139 immunocompromised patients (52 F/87 M) . The mean age was 26 years (3-56 years) . Our study included 33 children aged from 3 to 15 years, on whom 46 catheters were placed . The catheters were placed for the following indications: 145 catheters were used in subjects who received a bone marrow transplantation, 58 catheters were placed in subjects who received chemotherapy for acute leukemia and seven catheters were used in patients who received immunosuppressive therapy . RESULTS: The mean duration of catheterization was 33 days (7-114 days) . There were 3.1 catheter-related infections per 1000 catheter-days . Coagulase-negative Staphylococci were implicated in 64% of cases . We observed two pneumothorax (0.9%), one arterial puncture (0.4%) and two catheter-related thrombosis (0.9%) . CONCLUSION: Non-tunneled catheters in immunocompromised patients (adults and children) is a safe technique, and is an alternative to the Hickman catheters which are most widely used today in patients undergoing bone marrow transplantation.

J Neurosurg, 2003 Nov, 99(5), 831 - 9
Evaluation of an antibiotic-impregnated shunt system for the treatment of hydrocephalus; Govender ST et al.; OBJECT: Staphylococcus species are the most common organisms responsible for infection following implantable cerebrospinal fluid (CSF) diversionary procedures . The role of an antibiotic-impregnated shunt (AIS) system in the prevention of shunt infection has remained unclear because no human clinical trial has been reported on thus far . In this study, the authors assess an AIS system with respect to its prevention of shunt infection . METHODS: Patients were prospectively randomized into groups to evaluate the efficacy of an AIS system against an identical control shunt system . The data accrued were subjected to a detailed statistical analysis . Logistic regression analysis was performed to determine the independent association between outcome and predictor variables . Shunt function analysis was also performed to compare the average time to infection between the two groups . One hundred ten patients were recruited; 60 received control shunt systems and 50 received AIS systems . Thirteen shunt infections were recorded (10 in the control group and three in the AIS group) . Nine (69%) of 13 infections occurred within 2 months after shunt implantation (eight of 10 in the control group and one of three in the AIS group) . Apart from one patient in whom no organism was identified, a total of 14 organisms (12 patients) were cultured from either the CSF (nine) or the shunt apparatus (three) . Staphylococcus species accounted for the majority of shunt infections (83%): all 10 control shunts were found to have a positive culture of staphylococci, whereas none of the AISs had any staphylococci (p = 0.038) . CONCLUSIONS: The AIS afforded antistaphylococcal protection, especially during the early postoperative period when most shunt infections are known to occur and throughout the follow-up period (median 9 months) . The AIS system represents another important tool to enable the neurosurgeon to prevent shunt infections.

Eur J Clin Microbiol Infect Dis, 2003 Dec, 22(12), 746 - 8 Epub 2003 Nov 06.
Emergence of a teicoplanin-resistant small colony variant of Staphylococcus epidermidis during vancomycin therapy; Adler H et al.; Small colony variants of Staphylococcus aureus can cause persistent and recurrent infections . There are only a few reports of small colony variants of coagulase-negative staphylococci . Herein a case of infection with a teicoplanin-resistant small colony variant of Staphylococcus epidermidis is presented . The small colony variant was isolated from blood cultures of a patient with acute leukaemia and therapy-induced neutropenia who was treated with vancomycin for catheter-associated bloodstream infection . Despite removal of the catheter and adequate antibiotic therapy, the infection did not clear and the patient died 20 days after continuous antibiotic therapy.

Eur J Clin Microbiol Infect Dis, 2003 Dec, 22(12), 760 - 3 Epub 2003 Nov 07.
Molecular typing of coagulase-negative staphylococcal blood and skin culture isolates to differentiate between bacteremia and contamination; Krause R et al.; In order to determine whether a blood culture positive for coagulase-negative staphylococci (CNS) represents bacteremia or contamination, a prospective study was conducted using molecular typing to analyze CNS blood culture isolates and corresponding CNS skin isolates collected after skin disinfection from 431 subjects . CNS bacteremia was not found in any of the 301 subjects not suspected of having bacteremia . In 130 patients suspected of having bacteremia, the rate of actual CNS bacteremia was 6% . The overall rate of CNS blood culture contamination was 1% . Chart analysis showed good agreement between our microbiological definitions of bacteremia and the clinical definitions previously published . Bacteremia and contamination can be differentiated using pulsed-field gel electrophoresis and molecular typing of CNS isolates obtained from cultures of blood and corresponding skin samples.

J Cataract Refract Surg, 2003 Oct, 29(10), 2001 - 6
Infectious keratitis after laser in situ keratomileusis: results of an ASCRS survey; Solomon R et al.; To investigate the incidence, culture results, treatment, and visual outcomes of infectious keratitis after laser in situ keratomileusis (LASIK) worldwide, the Cornea Clinical Committee of the American Society of Cataract and Refractive Surgery (ASCRS) contacted 8600 United States and international ASCRS members by e-mail and asked them to respond to a questionnaire about post-LASIK infectious keratitis . One hundred sixteen infections were reported by 56 LASIK surgeons who had performed an estimated 338 550 procedures . Seventy-six cases presented in the first week after surgery, 7 during the second week, 17 between the second and fourth weeks, and 16 after 1 month . Forty-seven cases were not diagnosed on initial presentation . The most common organisms cultured were atypical mycobacteria and staphylococci . Empiric therapy is not recommended as most of the organisms are opportunistic and not responsive to conventional therapy . Flap elevation and culturing should be performed when post-LASIK infectious keratitis is suspected.

Perit Dial Int, 2003 Sep-Oct, 23(5), 465 - 8
A 12-month review of peritoneal dialysis-related peritonitis in Western Australia: is empiric vancomycin still indicated for some patients?
Kan GW, Thomas MA, Heath CH.
BACKGROUND: The International Society for Peritoneal Dialysis (ISPD) guidelines recommend empiric therapy with cefazolin and ceftazidime for peritoneal dialysis (PD)-related peritonitis . Empiric cefazolin therapy may have diminishing efficacy because of emerging methicillin resistance in gram-positive bacteria (GPB) . Western Australia also has large numbers of Aboriginal and isolated regional patients, where giving these antimicrobials can be impractical . OBJECTIVES: To evaluate, based on local antimicrobial resistance patterns, the feasibility of following ISPD guidelines in Western Australia and to identify any subgroups of PD peritonitis patients that may benefit from alternative empiric intraperitoneal antibiotics (e.g., vancomycin) . STUDY DESIGN: Retrospective study of all PD peritonitis episodes in Western Australia from 1 February 2000 to 31 January 2001 . SETTING: Three adult tertiary referral university hospitals and their PD patients in metropolitan Perth and regional Western Australia . PATIENTS: All adults on PD in Western Australia . MAIN OUTCOME MEASURE: Isolates and antibiograms were analyzed versus patient characteristics, including race and patient demographics . RESULTS: 293 patients (28% Aborigines, 32% regional patients) received PD . 145 episodes of PD peritonitis occurred during the study . The overall PD peritonitis rate was 1 episode/16 patient months, with Aborigines having 1 episode/10.5 patient months versus non-Aborigines having 1 episode/17 patient months (p < 0.001) . 36% of isolates from PD peritonitis episodes were resistant to cefazolin or ceftazidime . 22% were methicillin-resistant GPB (MR-GPB) {18% coagulase-negative staphylococci (CoNS), 1.6% MR Staphylococcus aureus}; 2.5% were multidrug-resistant gram-negative bacteria (MDR-GNB); 5.7% were polymicrobial (MR-GPB and/or MDR-GNB); and 5.7% were fungal . 63% of CoNS were methicillin resistant . Non-Aboriginal patients yielded MR-GPB in 22% of isolates versus 23% in Aborigines (p = 0.9) . Six of seven cases of fungal peritonitis occurred in Aboriginal patients (p < 0.001) . CONCLUSIONS: In our study population the ISPD guidelines were appropriate for 64% of patients with PD peritonitis . We could not identify specific patient subgroups where empiric cefazolin use could be more effective . High proportions of MR-GPB PD peritonitis episodes, along with local factors, make empiric cefazolin unsuitable for many regional PD patients in Western Australia.

Int J Antimicrob Agents, 2003 Nov, 22(5), 502 - 7
Tentative interpretative zone diameters for fusidic acid Neosensitabs on Mueller Hinton agar and three blood containing media; Skov R et al.; Two hundred and ninety-two staphylococci were tested using fusidic acid Neosensitabs, a semiconfluent inoculum on Mueller Hinton agar and three blood containing agar media in order to investigate the interpretative zone diameters published by the manufacturer (Rosco) . Zone diameters were, as expected, smaller on blood containing agar compared with Mueller Hinton agar . Many susceptible strains were intermediate on Danish Blood agar using the current breakpoints . We suggest that the interpretative zone diameters be changed to S>or=32, R<or=30 for Mueller Hinton agar and S>or=24, R<or=22 on blood containing media.

Biochemistry, 2003 Nov 11, 42(44), 12835 - 43
Crystal structure of the sensor domain of the BlaR penicillin receptor from Bacillus licheniformis; Kerff F et al.; As in several staphylococci, the synthesis of the Bacillus licheniformis 749/I beta-lactamase is an inducible phenomenon regulated by a signal-transducing membrane protein BlaR . The C-terminal domain of this multimodular protein is an extracellular domain which specifically recognizes beta-lactam antibiotics . When it binds a beta-lactam, a signal is transmitted by the transmembrane region to the intracellular loops . In response, the hydrolytic activity of the BlaR large cytoplasmic L3 loop is induced, and a cascade of reactions is generated, leading to the transcription of the beta-lactamase gene . Here, we describe the crystal structure of the extracellular penicillin-receptor domain of BlaR (residues 346-601) at 2.5 A resolution in order to understand why this domain, whose folding is very similar to that of class D beta-lactamases, behaves as a highly sensitive penicillin-binding protein rather than a beta-lactamase . Two residues of the BlaR C-terminal domain, Thr452 and Thr542, modify the hydrophobic characteristic of the class D beta-lactamase active site . Both residues seem to be in part responsible for the lack of beta-lactamase activity of the BlaR protein due to the stability of the acyl-enzyme . Although further experimental data are needed to fully understand the transmembrane induction process, the comparison of the BlaR sensor domain structure with those of class D beta-lactamase complexes and penicillin-binding proteins provides interesting elements to hypothesize on possible signal transmission mechanisms.

Am J Vet Res, 2003 Oct, 64(10), 1213 - 20
Anti-inflammatory effects of intramammary infusions of glycyrrhizin in lactating cows with mastitis caused by coagulase-negative staphylococci; Kai K et al.; OBJECTIVE: To determine the anti-inflammatory effects of glycyrrhizin (GL) in lactating cows with mastitis attributable to naturally occurring infection with coagulase-negative staphylococci (CNS) . ANIMALS: 12 lactating Holstein cows with mastitis attributable to infection with CNS and 2 healthy cows without mastitis . PROCEDURE: Clinical signs, number of bacteria in milk, somatic cell count (SCC) in milk, concentrations of alpha-lactalbumin and lactoferrin in milk, and concentration of histamine in milk were investigated before and after intramammary infusion of GL (6 cows) or antimicrobials (6 cows) . Glands of 2 healthy cows were infused with staphylococcal enterotoxin; milk leukocytes were then harvested and incubated with various doses of GL . RESULTS: In cows infected with CNS that had a low bacterial concentration in milk, infusion of GL alone resulted in significant improvements in swelling, firmness of glands, and number of clots in milk, and it decreased the SCC, but not significantly . Percentage of neutrophils decreased significantly (to < 30%) by 2 days after infusion . Use of lactoferrin as a marker of inflammation in mammary glands revealed a decrease in concentrations, whereas use of alpha-lactalbumin as a marker of recovery for mammary glands revealed significant increases in concentrations in the GL-infused group . Accompanying these anti-inflammatory effects, a decrease in the concentration of histamine in milk was observed in the GL-infused group . Glycyrrhizin decreased histamine production by milk leukocytes in a concentration-dependent manner . CONCLUSIONS AND CLINICAL RELEVANCE: Infusion of GL may regulate intramammary inflammation through modulation of inflammatory mediators such as histamine.

Mikrobiyol Bul, 2003 Apr-Jun, 37(2-3), 109 - 15
{Comparison of the value of disk diffusion methods and polymerase chain reaction for fixation of methicillin resistant staphylococcus}; Sancak B et al.; The detection of methicillin resistance with an appropriate method has a great importance in the treatment of infectious diseases caused by staphylococci . This study was set out to compare disk diffusion method as a phenotypic method, with polymerase chain reaction (PCR), as a genotypic method, for the detection of methicillin resistance in staphylococci . A total of 406 staphylococci strains that were isolated from clinical specimens in microbiology laboratories of adult hospital of Hacettepe University Medical Faculty were included into the study . Of 406 strains, 248 were identified as Staphylococcus aureus, and 158 were coagulase-negative staphylococci (CNS) . When the disk diffusion test was compared to PCR for the detection of methicillin resistance, sensitivity and specificity were found as 100% for S . aureus (respectively, 106/106 and 142/142), whereas for CNS sensitivity was 100% (86/86) and specificity was 79% (57/72) . For CNS, if zone diameter for resistance was accepted as < or = 14 mm instead of < or = 17 mm, all of the mecA positive strains were found as resistant, whereas three mecA negative strains appeared to be resistant by disk diffusion method {sensitivity: 100% (86/86), specificity: 95.8% (69/72)} . Although disk diffusion was found as a reliable method for the detection of methicillin resistance in S.aureus isolates, it couldn't show the same success in CNS . For that reason in order to obtain the zone diameter for CNS, further studies are needed.

J Antimicrob Chemother, 2003 Dec, 52(6), 993 - 1000 Epub 2003 Oct 29.
Piperacillin-tazobactam versus ciprofloxacin plus amoxicillin in the treatment of infective episodes after liver transplantation; Philpott-Howard J et al.; An optimum antimicrobial regimen for bacterial infection after orthotopic liver transplantation has not been identified . In this prospective 4 year study of patients undergoing liver transplantation, patients were randomized to receive either piperacillin-tazobactam (112 patient episodes) or ciprofloxacin plus amoxicillin (105 patient episodes) for empirical treatment of infective episodes in the first 3 months after transplant . Metronidazole was added to the ciprofloxacin-amoxicillin regimen where anaerobic infection was suspected . Patient groups were comparable with respect to clinical, biochemical and haematological parameters . At the 72 h primary efficacy end-point, the overall response rate for the intention-to-treat group was 74/112 (66.1%) for piperacillin-tazobactam and 63/105 (60.0%) for ciprofloxacin plus amoxicillin (P=0.399); the corresponding figures for the per-protocol (PP) group were 73/82 (89.0%) (piperacillin-tazobactam) and 61/80 (76.3%) (ciprofloxacin plus amoxicillin) (P=0.038) . At the end-of-study assessment, 58.9% of episodes in the piperacillin-tazobactam group had a successful clinical outcome, compared with 50.5% in the ciprofloxacin plus amoxicillin group (P=0.222); the corresponding figures for the PP group were 83.5% (piperacillin-tazobactam) and 68.8% (ciprofloxacin plus amoxicillin) (P=0.038) . Staphylococci and aerobic Gram-negative bacilli were the predominant pathogens in both groups . Bacteria resistant to the study drugs were encountered, including methicillin-resistant Staphylococcus aureus, vancomycin-resistant Enterococcus faecium and multiply-resistant Klebsiella spp . Empirical monotherapy with piperacillin-tazobactam is an effective treatment for infective episodes in liver transplant patients.

Clin Infect Dis, 2003 Nov 15, 37(10), 1392 - 5 Epub 2003 Oct 23.
Serum bactericidal activity of the methoxyfluoroquinolones gatifloxacin and moxifloxacin against clinical isolates of Staphylococcus species: are the susceptibility breakpoints too high?
Stein GE, Schooley S, Kaatz GW.
Healthy volunteers received a single dose of gatifloxacin and moxifloxacin (400 mg each), and serum samples were obtained from these volunteers over a 24-h period . Prolonged (> or =12 h) serum bactericidal activity (SBA) was observed for both agents against staphylococcal isolates with minimum inhibitory concentrations (MICs) of gatifloxacin of < or =0.5 mug/mL . In strains with gatifloxacin MICs of 1.0 mug/mL, SBA was observed for < or =6 h, and, for isolates with gatifloxacin MICs of 2.0 mug/mL, little or no SBA was observed for either drug . The relative lack of SBA against less susceptible strains of staphylococci suggests that the current susceptibility breakpoint concentration (MIC, 2.0 mug/mL) for these methoxyfluoroquinolones against Staphylococcus is too high.

Med Dosw Mikrobiol, 2003, 55(2), 109 - 15
{Phenotypic characteristics of coagulase-negative Staphylococci colonizing pleural drains in patients with lung cancer after thoracic surgery}; Korona-Glowniak I et al.; Coagulase-negative staphylococci (CNS) represent an important group of etiologic agents of infections associated with plastic biomaterials, e.g . drains . In the present paper 33 strains of CNS were characterized . All of them were isolated from fluid of pleural drains in patients with lung cancer after pulmonary resection under conditions of antimicrobial prophylaxis . The most frequently isolated species were Staphylococcus epidermidis and S . warneri . The majority of CNS strains showed ability to produce slime and possessed hydrophobic properties of cell surface . Strains of CNS resistant to penicillin and oxacillin, but sensitive to amoxicillin/clavulanate were isolated most frequently . Only two methicillin-resistant strains, belonging to S . haemolyticus, were found . The obtained data indicate that CNS strains colonizing pleural drains had potential ability to adhere to smooth surfaces . Most of isolated strains were susceptible to antibiotics and chemotherapeutics routinely used in staphylococcal infections.

Antimicrob Agents Chemother, 2003 Nov, 47(11), 3574 - 9
Related clones containing SCCmec type IV predominate among clinically significant Staphylococcus epidermidis isolates; Wisplinghoff H et al.; SCCmec is a mobile genetic element that carries the gene (mecA) mediating methicillin resistance in staphylococci . For Staphylococcus aureus, four SCCmec types have been described, one (type IV) of which has been associated with newly identified community-acquired methicillin-resistant S . aureus . However, the distribution of SCCmec types among S . epidermidis is not known . SCCmec typing of a collection of 44 methicillin-resistant Staphylococcus epidermidis (MRSE) isolates recovered between 1973 and 1983 from the blood of patients with prosthetic valve endocarditis (PVE) was performed by PCR amplification of key genetic elements (mecA, mecI, IS1272, and ccrAB) . Of the 44 isolates, 1 (2%) harbored SCCmec type I, 15 (34%) harbored type II, 12 (28%) harbored type III, and 16 (36%) harbored type IV . The complete nucleotide sequence of SCCmec type IV was determined for 16 isolates and found to be identical in size (24 kb) and 98% homologous to DNA sequences published for S . aureus . Type IV SCCmec was also common (5 of 10 isolates) among a geographically dispersed collection of 10 recent (1998 to 2001) S . epidermidis bloodstream isolates . Multilocus sequence typing (MLST) (using the same seven genes presently employed for S . aureus MLST) of these MRSE isolates and of 10 additional recent geographically dispersed methicillin-susceptible isolates demonstrated that all 16 PVE isolates and 2 of 5 recent isolates harboring type IV SCCmec were in three related clonal groups . All three MSSE PVE isolates recovered from patients between 1976 and 1979 were in the same clonal groups as type IV SCCmec MRSE isolates . These data support the hypothesis of intra- and interspecies transfer of type IV SCCmec and suggest that there are clonal associations in S . epidermidis that correlate with SCCmec type.

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