Enterococci

Diagn Microbiol Infect Dis, 2003 Jan, 45(1), 81 - 4
Real-time PCR for the rapid detection of vanA and vanB genes; Palladino S et al.; A real-time PCR assay suitable for use on the Roche LightCycler platform was developed to replace an existing gel-based PCR assay for the simultaneous detection of the vanA & vanB genes in enterococcal isolates . Novel Fluorescence Resonance Energy Transfer (FRET) hybridization probes were designed . The multiplex real-time PCR assay and the existing gel-based assay were 100% concordant and both correctly detected the vanA or vanB genes in 4/4 VanA E . faecium and 25/25 VanB E . faecium . Additionally, 1/1 VanC1 E . gallinarum, 1/1 VanC2 E . casseliflavus and 47/47 vancomycin susceptible enterococci were negative for the vanA and vanB genes in both PCR assays . Results were available within 1.5 h for the real-time PCR assay compared to up to 5.5 h for the conventional PCR assay.

Biometals, 2003 Mar, 16(1), 137 - 43
The Enterococcus hirae paradigm of copper homeostasis: copper chaperone turnover, interactions, and transactions; Lu ZH et al.; The cop operon is a key element of copper homeostasis in Enterococcus hirae . It encodes two copper ATPases, CopA and CopB, the CopY repressor, and the CopZ metallochaperone . The cop operon is induced by copper, which allows uncompromised growth in up to 5 mM ambient copper . Copper uptake appears to be accomplished by the CopA ATPase, a member of the heavy metal CPx-type ATPases and closely related to the human Menkes and Wilson ATPases . The related CopB ATPase extrudes copper when it reaches toxic levels . Intracellular copper routing is accomplished by the CopZ copper chaperone . Using surface plasmon resonance analysis, it was demonstrated that CopZ interacts with the CopA ATPase where it probably becomes copper loaded . CopZ in turn can donate copper to the copper responsive repressor CopY, thereby releasing it from DNA . In high copper, CopZ is proteolyzed . Cell extracts were found to contain a copper activated proteolytic activity that degrades CopZ in vitro . This post-translational control of CopZ expression presumably serves to avoid the accumulation of detrimental Cu-CopZ levels.

Clin Infect Dis, 2003 Feb 15, 36(4), 440 - 6 Epub 2003 Jan 24.
Changes in the prevalence of vancomycin-resistant enterococci in response to antimicrobial formulary interventions: impact of progressive restrictions on use of vancomycin and third-generation cephalosporins; Lautenbach E et al.; This study sought to assess the impact of restricting use of vancomycin and third-generation cephalosporins on vancomycin-resistant enterococci (VRE) prevalence . All clinical enterococcal isolates identified at a large academic medical center during a 10-year period were analyzed . Changes in VRE prevalence after sequential restrictions on use of vancomycin and third-generation cephalosporins were evaluated . The correlation between antibiotic use and VRE prevalence was also investigated . Vancomycin use initially decreased by 23.9% but returned to preintervention levels by the end of the study . Third-generation cephalosporin use decreased by 85.8% . However, VRE prevalence increased steadily from 17.4% to 29.6% during the 10-year period (P<.001) . Clindamycin use was significantly correlated with VRE prevalence . Restricting the use of vancomycin and third-generations cephalosporins had little impact on VRE prevalence . The association between clindamycin use and the prevalence of VRE suggests that restriction of this and perhaps other antianaerobic agents might be an important component of future antimicrobial interventions.

J Infect Dis, 2003 Feb 1, 187(3), 508 - 12 Epub 2003 Jan 08.
A potential virulence gene, hylEfm, predominates in Enterococcus faecium of clinical origin; Rice LB et al.; An open reading frame (hyl(Efm)) with homologies to previously described hyaluronidase genes has been identified in nonstool isolates of Enterococcus faecium . E . faecium isolates (n=577) from diverse sources were screened for the presence of hyl(Efm) and esp(Efm), a putative virulence gene associated with epidemic E . faecium strains . The presence of esp(Efm) was roughly twice that of hyl(Efm), but both were found primarily in vancomycin-resistant E . faecium isolates in nonstool cultures obtained from patients hospitalized in the United States . These data suggest that specific E . faecium strains may be enriched in determinants that make them more likely to cause clinical infections . Differences in the prevalence of these strains may help explain variations in the clinical importance of multiresistant E . faecium across different continents.

Antimicrob Agents Chemother, 2003 Feb, 47(2), 786 - 9
Nonconjugative transposition of the vanB-containing Tn5382-like element in Enterococcus faecium; Dahl KH et al.; The vanB2 operon encoding glycopeptide resistance is an integral part of the putative conjugative transposon Tn5382 . Characterization of clinical glycopeptide resistant derivatives from an epidemic ampicillin-resistant Enterococcus faecium strain showed precise chromosomal or plasmid insertions of a vanB2-containing Tn5382-like element . Conjugative transposition of the Tn5382-like element was not demonstrated in retransfer studies.

J Microbiol Methods, 2003 Mar, 52(3), 341 - 51
Evaluation of a novel method based on amplification of DNA fragments surrounding rare restriction sites (ADSRRS fingerprinting) for typing strains of vancomycin-resistant Enterococcus faecium; Krawczyk B et al.; In the search for an effective DNA-typing technique for use in hospital epidemiology, the performance and convenience of a novel assay based on the fingerprinting of bacterial genomes by amplification of DNA fragments surrounding rare restriction sites (ADSRRS fingerprinting) was tested . A large number of vancomycin-resistant Enterococcus faecium (VREM) isolates from haematological ward patients of the Clinical Hospital in Gdansk were examined . We found that ADSRRS fingerprinting analysis is a rapid method that offers good discriminatory power . The method demonstrated also excellent reproducibility . The usefulness of the ADSRRS fingerprinting method for molecular typing was compared with pulsed field gel electrophoresis (PFGE) method, which is currently considered the gold standard for molecular typing of isolates recovered from patients and the environment in the course of investigation and control of nosocomial outbreaks . Clustering of ADSRRS fingerprinting data matched pulsed field gel electrophoresis data.The features of ADSRRS fingerprinting technique is discussed in comparison with conventional methods . Data presented here demonstrate the complexity of the epidemiological situation concerning VREM that may occur in a single medical ward.

Microb Drug Resist, 2002 Winter, 8(4), 369 - 74
Streptogramin resistance among Enterococcus faecium isolated from production animals in Denmark in 1997; Jensen LB et al.; The genetic background for streptogramin resistance was examined in Enterococcus faecium isolated from pigs (n = 55) and broilers (n = 207) in 1997 in Denmark . Fifty-one percent and 67%, respectively, of the isolates were resistant to streptogramins . Among streptogramin-resistant E . faecium (SREF), the genetic background for streptogramin A resistance could be determined in 96% of the isolates from broilers, compared with 14% among SREF from pigs . For broiler isolates 89% of SREF contained the vat(E) gene and 10% the vat(D) gene . Three of these isolates contained both resistance genes . Among SREF from pigs two isolates contained the vat(E) gene and two others the vat(D) gene . The genetic background for streptogramin B was most often identified as the erm(B) gene encoding macrolide, lincosamide, and streptogramin B (MLSB) resistance . Among SREF, 84% and 86% of isolates from broilers and pigs, respectively, contained the erm(B) . In SREF from broilers, the erm(B) gene was physically linked to the vat(E) gene in 62% of the vat(E)-positive isolates and 79% of the isolates containing vat(D) . erm(A) was detected in two SREF of broiler origin . Both isolates also contained the erm(B) gene . No SREF contained the vgb(A) gene encoding streptogramin B resistance . On the basis of genetic characterization, streptogramin-resistant isolates from broiler were divided into subgroups, according to the presence of the streptogramin A genes, to determine possible co-resistance to antimicrobials, especially glycopeptides . Twenty-five percent of the SREF from broilers were glycopeptide resistant (MIC > 16 microg/ml) . None of the isolates containing the streptogramin A gene vat(D) was resistant to glycopeptide, whereas isolates containing the vat(E) gene had a lower prevalence to glycopeptide resistance than the streptogramin-sensitive isolates.

Microb Drug Resist, 2002 Winter, 8(4), 355 - 61
Persistence of vancomycin-resistant enterococci (VRE) in broiler houses after the avoparcin ban; Heuer OE et al.; The glycopeptide growth promoter avoparcin was banned from animal production in the EU in 1997 due to concern for the spread of vancomycin-resistant enterococci (VRE) from food animals to humans . In recent Norwegian and Danish studies, extensive occurrence of VRE on broiler farms and in broiler flocks after the avoparcin ban has been reported . The present study was undertaken to investigate the epidemiology of VRE on broiler farms in the absence of the selective pressure exerted by avoparcin . Environmental samples were obtained from five broiler houses after depopulation, cleaning, and disinfection of the houses between rotations, and two consecutive broiler flocks from each house were sampled by taking cloacal swabs from the broilers at the time of slaughter . A total of 69 vancomycin-resistant Enterococcus faecium isolates obtained from broiler flocks and broiler houses were subjected to molecular typing by pulsed-field gel electrophoresis (PFGE) . Forty-one PFGE-profiles were observed . VRE with indistinguishable or highly similar PFGE profiles were isolated from consecutive broiler flocks and from environmental samples from the houses in which the flocks were reared, whereas VRE-isolates from different broiler houses and from flocks reared in different houses appeared to be genetically unrelated . These findings indicated that VRE was transmitted between consecutive broiler flocks by clones of resistant bacteria surviving in the broiler houses despite cleaning and disinfection between rotations . Thus, the extensive occurrence of VRE in broiler flocks after the avoparcin ban may be explained by persistence of VRE in the broiler house environment.

J Gastroenterol, 2002, 37(12), 1062 - 7
A pancreatic abscess 7 years after a pancreatojejunostomy for calcifying chronic pancreatitis; Suzuki A et al.; We present herein a case of a 75-year-old Japanese man who had developed a pancreatic abscess 7 years after a longitudinal pancreatojejunostomy for chronic pancreatitis . The patient, a heavy drinker of alcohol, underwent surgical decompression of a ductal obstruction to relieve persistent abdominal pain due to severely calcifying chronic pancreatitis . After the surgery, he stopped drinking alcohol and was treated with insulin to control secondary diabetes mellitus . Thereafter, his symptoms disappeared . Seven years after the surgery, however, he was hospitalized due to obstructive jaundice, high-grade fever, and right hypochondria pain . Ultrasound and computed tomographic scans of the abdomen both disclosed a cystic mass, approximately 6 cm in size, in the pancreatic head . Magnetic resonance imaging strongly suggested a pancreatic abscess with necrotic fluid and debris . First, percutaneous transhepatic cholangiodrainage (PTCD) was done to treat the progressively obstructive jaundice . Subsequently, fine-needle aspiration of the pancreatic abscess was performed under ultrasound guidance . Enterococcus avium and Klebsiella oxytoca were revealed by culture of abscess aspirates . He was successfully cured by treatment with both appropriate antibiotic and continuous PTCD for the obstructive jaundice.

Appl Environ Microbiol, 2003 Jan, 69(1), 92 - 6
Enterococci as indicators of Lake Michigan recreational water quality: comparison of two methodologies and their impacts on public health regulatory events; Kinzelman J et al.; The frequency of poor-water-quality advisories issued in Milwaukee and Racine, Wisconsin, in the absence of identifiable sources of contamination brought into question the reliability of the present indicator organism, Escherichia coli . Enteroccoci have been suggested as an alternative to E . coli for freshwater monitoring due to their direct correlation to swimmer-associated gastroenteritis . The purpose of this research was threefold: (i) to explore enterococci as an alternative to E . coli for monitoring freshwater Lake Michigan beaches, (ii) to evaluate the impact of the two indicators on regulatory decisions, and (iii) to compare membrane filtration m-enterococcus agar with indoxyl-beta-D-glucoside to a chemical substrate technique (Enterolert) for the recovery of enterococci . Recreational water samples from Milwaukee (n = 305) and Racine (n = 153) were analyzed for the enumeration of E . coli and enterococci using IDEXX Colilert-18 and Enterolert . Correlation between the indicators was low (R(2) = 0.60 and 0.69) . Based on U.S . Environmental Protection Agency bacterial indicator threshold levels of risk for full body immersion, using enterococci would have resulted in 56 additional unsafe-recreational-water-quality advisories compared to the total from using E . coli and the substrate-based methods . A comparison of the two enterococcal methods (n = 124) yielded similar results (R(2) = 0.62) . This was further confounded by the frequent inability to verify enterococci from those wells producing fluorescence by the defined substrate test using conventional microbiological methods . These results suggest that further research is necessary regarding the use of defined substrate technology interchangeably with the U.S . Environmental Protection Agency-approved membrane filtration test for the detection of enterococci from fresh surface water.

Folia Microbiol (Praha), 2002, 47(5), 573 - 8
Treatment of experimental adjuvant arthritis with the combination of methotrexate and lyophilized Enterococcus faecium enriched with organic selenium; Rovensky J et al.; The efficacy of combination therapy with methotrexate (MTX) and probiotic bacteria Enterococcus faecium enriched with organic selenium (EFSe) in rats with adjuvant arthritis was determined . Rats with adjuvant arthritis were given MTX (0.3 mg/kg 2-times weekly, orally); lyophilized E . faecium enriched with Se (15 mg/kg, 5 d per week, orally); and a combination of MTX plus EFSe for a period of 50 d from the immunization . Levels of serum albumin, serum nitrite/nitrate concentrations, changes in hind paw swelling, arthrogram score, bone erosions, whole body bone mineral density (BMD) and bone mineral content (BMC) were assayed in the rats as variables of inflammation and destructive arthritis-associated changes . Treatment with MTX and with the combination MTX + EFSe significantly inhibited markers of both inflammation and arthritis . Significant differences in favor of combination therapy with MTX + EFSe as compared to MTX alone were seen in serum albumin concentration, hind paw swelling and arthrogram score . Reductions in radiographic scores were also more pronounced in the combination therapy group . Combination therapy, but not MTX alone, inhibited the reduction of BMD and BMC; treatment with lyophilized EFSe alone had no significant effect on adjuvant arthritis in rats . The potent therapeutic effect of low dosage MTX therapy in combination with lyophilized EFSe on adjuvant arthritis in rats was shown.

Microbiol Res, 2002, 157(4), 293 - 303
Lectin-like binding and antibiotic sensitivity of enterococci from wild herbivores; Styriak I et al.; Fifty eight enterococcal isolates from wild herbivores were tested for their antibiotic sensitivity pattern and lectin-like binding of extracellular matrix (ECM) and serum proteins . Kanamycin resistance was very frequent; many multiresistant strains were also isolated . All isolates were sensitive to rifampicin . Resistance to gentamicin, novobiocin, and tetracycline was widely distributed in the microflora of wild herbivores breeded in zoological garden in Kosice . No autoaggregating strains were detected among these 58 enterococcal isolates . Various degrees of binding of mucins, fetuin, heparin, fibrinogen, and fibronectin were observed in individual strains . However, bovine lactoferrin binding by enterococci from deers and chamoises was either negative (0) or strongly positive (3) . With regard to influence of growth media, TH agar was found to be better for the expression of lectin-like binding than blood agar, TH broth and Nutrient broth . A significant effect (P < 0.001 or P < 0.05) of proteolytic treatment was observed in six selected strains . However, there is a difference between the effect of trypsin and pronase P . Pronase treatment more effectively decreased binding of some strains (1H, 6A, EF 1111, EC 1292), while trypsin treatment decreased more binding of other enterococcal strains (EF 953 and 1E) . Significant (P < 0.001) influence of metaperiodate, which cleaves the C-C bond between vicinal groups of sugars, on collagen I binding by three selected strains (1E, 1H, 6A) and bovine lactoferrin binding (by EF 1111, EC 1292, EF 953) was also observed . However, its influence was very different . In two strains (1H and EC 1292), ECM binding was decreased, while in four other strains (1E, 6A, EF 1111, EF 953) it was increased.

Antimicrob Agents Chemother, 2003 Jan, 47(1), 7 - 18
VanD-type vancomycin-resistant Enterococcus faecium 10/96A; Depardieu F et al.; VanD type Enterococcus faecium 10/96A is constitutively resistant to vancomycin and to low levels of teicoplanin by nearly exclusive synthesis of peptidoglycan precursors terminating in D-alanyl-D-lactate (L . M . Dalla Costa, P . E . Reynolds, H . A . Souza, D . C . Souza, M . F . Palepou, and N . Woodford, Antimicrob . Agents Chemother . 44:3444-3446, 2000) . A G(184)S mutation adjacent to the serine involved in the binding of D-Ala1 in the D-alanine:D-alanine ligase (Ddl) led to production of an impaired Ddl and accounts for the lack of D-alanyl-D-alanine-containing peptidoglycan precursors . The sequence of the vanD gene cluster revealed eight open reading frames . The organization of this operon, assigned to a chromosomal location, was similar to those in other VanD type strains . The distal part encoded the VanH(D) dehydrogenase, the VanD ligase, and the VanX(D) dipeptidase, which were homologous to the corresponding proteins in VanD-type strains . Upstream from the structural genes for these proteins was the vanY(D) gene; a frameshift mutation in this gene resulted in premature termination of the encoded protein and accounted for the lack of penicillin-susceptible D,D-carboxypeptidase activity . Analysis of the translated sequence downstream from the stop codon, but in a different reading frame because of the frameshift mutation, indicated homology with penicillin binding proteins (PBPs) with a high degree of identity with VanY(D) from VanD-type strains . The 5' end of the gene cluster contained the vanR(D)-vanS(D) genes for a putative two-component regulatory system . Insertion of ISEfa4 in the vanS(D) gene led to constitutive expression of vancomycin resistance . This new insertion belonged to the IS605 family and was composed of two open reading frames encoding putative transposases of two unrelated insertion sequence elements, IS200 and IS1341.

J Am Coll Surg, 2002 Dec, 195(6), 804 - 13
Portal versus systemic drainage of small bowel allografts: comparative assessment of survival, function, rejection, and bacterial translocation; Berney T et al.; BACKGROUND: Portal venous drainage of small bowel grafts is theoretically more physiologic than systemic drainage, but is technically more demanding . Comparisons in animal models have not demonstrated a clear advantage of one technique over the other, but clinical data are lacking . STUDY DESIGN: Clinical records of 36 patients who underwent 37 small bowel transplantation procedures from January 1995 to August 2001 were reviewed . Portal drainage was performed in 19 patients (PD group) . Systemic drainage was performed in 18 patients (SD group) . Median followup was 531 days . RESULTS: PD and SD patients had similar ICU stays (median 7 versus 9 days) and endotracheal intubation durations (median 3 versus 5 days) . All current survivors, with the exception of one patient in each group, are independent from parenteral nutrition . Liver function tests were similar in both groups . There was a twofold increase in tacrolimus dosage in the PD group to achieve similar trough levels indicating a "first-pass" hepatic clearance effect . Cumulative incidence of acute rejection episodes and OKT3-requiring rejection episodes were similar in both groups . To the contrary, a lower incidence of gram-negative rods of Enterococcus sp . in blood or bronchoalveolar lavage suggested that the clearance of translocated intestinal bacteria was more efficient in the PD group . Graft and patient survival rates were similar in both groups . CONCLUSIONS: Systemic venous drainage of small bowel transplants is a dependable technique, associated with similar results as portal venous drainage, in terms of overall mortality, morbidity, rejection, function, and patient and graft survival . But attention should be paid to an impaired clearance of intestinal bacterial translocation after systemic drainage.

Chest, 2002 Dec, 122(6), 2259 - 62
Bacterial endocarditis and functional mitral stenosis: a report of two cases and brief literature review; Tiong IY et al.; Mitral valve endocarditis typically results in mitral regurgitation . However, endocarditis leading to functional mitral stenosis is uncommon and, when present, fungal organisms are typically implicated . Thus, obstructive-type bacterial endocarditis due to large vegetations blocking the mitral valve orifice is a rare occurrence, with approximately 20 reported cases in the literature . We report on two patients with bacterial endocarditis and severe functional mitral stenosis requiring emergent surgery . Additionally, this is the first report of vancomycin-resistant enterococcus causing endocarditis and functional mitral stenosis . The discussion emphasizes the hemodynamic instability of these patients and need for early surgical intervention.

J Hosp Infect, 2002 Dec, 52(4), 292 - 6
Emergence of vancomycin-resistant Enterococcus faecium at a tertiary care hospital in Karachi, Pakistan; Khan E et al.; Vancomycin-resistant enterococcus (VRE) has not been reported previously in Pakistan . This is the first report where in vancomycin-resistant Enterococcus faecium was isolated from the clinical specimens of six patients admitted to the intensive care unit (ICU) and neonatal intensive care unit (NICU) of the Aga Khan University Hospital, Karachi . To identify the extent of the outbreak, rectal swabs were obtained from all the patients admitted to the ICU and NICU at that time . A total of 10 strains of vancomycin-resistant Enterococcus faecium were isolated . All the strains showed high-level resistance to both glycopeptides (vancomycin and teicoplanin) with a vancomycin minimum inhibitory concentration greater than 256 mg/L . All isolates had the vanA gene detected by polymerase chain reaction . The contour-clamped homogeneous electric field (CHEF) pattern demonstrated that all but one of the isolates were of a single clone, suggesting that they were derived from common source . Use of vancomycin and prolonged hospitalization were common features in all cases investigated .

Biochem J, 2003 Apr 1, 371(Pt 1), 191 - 7
Biochemical and genetic characterization of a novel enzyme of pentitol metabolism: D-arabitol-phosphate dehydrogenase; Povelainen M et al.; An enzyme with a specificity that has not been described previously, D-arabitol-phosphate dehydrogenase (APDH), has been purified from cell lysate of Enterococcus avium . SDS/PAGE indicated that the enzyme had a molecular mass of 41+/-2 kDa, whereas a molecular mass of 160+/-5 kDa was observed under non-denaturing conditions, implying that the APDH may exist as a tetramer with identical subunits . Purified APDH was found to have a narrow substrate specificity, converting only D-arabitol 1-phosphate and D-arabitol 5-phosphate into xylulose 5-phosphate and ribulose 5-phosphate, respectively, in the oxidative reaction . Both NAD(+) and NADP(+) were accepted as cofactors . Based on the partial protein sequences, the APDH gene was cloned . Homology comparisons place APDH within the medium-range dehydrogenase family . Unlike most members of this family, APDH requires Mn(2+) but no Zn(2+) for enzymic activity . The DNA sequence surrounding the gene suggests that it belongs to an operon that also contains several components of phosphotransferase system . Both biochemical evidence and protein sequence homology comparisons indicate that similar enzymes are widespread among the Gram-positive bacteria . Their apparent biological role is to participate in arabitol catabolism via the 'arabitol phosphate route', similar to the ribitol and xylitol catabolic routes described previously.

Fish Shellfish Immunol, 2002 Nov, 13(5), 351 - 65
Effect of hypoxia on the immune response of giant freshwater prawn Macrobrachium rosenbergii and its susceptibility to pathogen Enterococcus; Cheng W et al.; Giant freshwater prawns Macrobrachium rosenbergii (14-19 g) were challenged with Enterococcus (3 x 10(5) cfu prawn(-1)) previously incubated in TSB medium for 24 h, then placed in water having concentrations of dissolved oxygen (DO) at 7.75, 4.75, 2.75 and 1.75 mg l(-1) . Onset of mortality occurred after 6 h exposure to 1.75 mg l(-1) DO, and after 12 h exposure to 2.75 mg 1(-1) DO . Cumulative mortality of prawns at 1.75 mg l(-1) DO was significantly higher than that at 4.75 and 2.75 mg l(-1) DO, and cumulative mortality of prawns at 4.75 and 2.75 mg l(-1) DO was significantly higher than that at 7.75 mg l(-1) DO after 96 h . The prawns (20-30 g) which had been placed in water for 0 to 120 h at 7.75, 4.75, 2.75 and 1.75 mg l(-1) DO were examined for the THC (total haemocyte counts), DHC (differential haemocyte counts), phenoloxidase activity, respiratory burst, percentage phagocytosis and clearance efficiency . No significant difference in semi-granular cells and granular cells of prawns was observed among four treatments . The prawns following 120 h exposure to 2.75 mg l(-1) DO decreased significantly the hyaline cells and THC by 39% and 36%, respectively . Phenoloxidase activity and respiratory burst decreased significantly by 33% and 11% when the prawns were exposed to 2.75 mg l(-1) DO after 24 h, respectively . Percentage phagocytosis and clearance efficiency to Enterococcus decreased significantly by 44% and 54% for the prawns following 12 h exposure to 2.75 mg l(-1) DO, respectively . It is concluded that DO as low as 2.75 mg l(-1) and 4.75 mg l(-1) causes depression in immune system of M . rosenbergii, and increases its susceptibility to Enterococcus infection.

Int J Antimicrob Agents, 2002 Dec, 20(6), 432 - 7
Epidemiology of multiresistant Enterococcus avium isolates in a Greek tertiary care hospital; Papaparaskevas J et al.; A retrospective survey of the isolation rate of Enterococcus avium during the period March 1994-February 2000 conducted in Laikon General Hospital using the WHONET software, revealed a peak in the isolation rates of this species during March 1995-February 1996 . The ten strains isolated during this time were studied further . No glycopeptide resistance was detected but resistance to ampicillin, ciprofloxacin, erythromycin, gentamicin (high-level) and streptomycin (high-level) was present in nine, ten, nine, three and seven of the isolates, respectively . The genes aac(6')-Ie+aph(2")-Ia and ant(6)-I, encoding for high-level gentamicin and streptomycin resistance, respectively, were detected only in the isolates with the corresponding phenotypes . Beta-lactamase production and haemolysis were not detected . There was evidence of ward-, floor- and building-specific distribution among the different aminoglycoside resistance phenotypes . DNA fingerprinting by PFGE grouped six of the ten isolates in a single cluster with 83% similarity, even though they expressed various resistance phenotypes . These results suggest dissemination of resistance genes among both genetically related and unrelated strains .

Appl Environ Microbiol, 2002 Dec, 68(12), 6457 - 61
Vancomycin-resistant enterococci in humans and imported chickens in Japan; Ozawa Y et al.; The phenotypes and genotypes of 22 VanA-type vancomycin-resistant enterococci that had been isolated in Japan were examined . The VanA resistance determinant was plasmid mediated in each of the 22 strains . Of the 22 strains, 8 were isolated from different patients and 11 and 3 were obtained from different samples of chickens imported from Thailand and France, respectively . Three of the strains that were isolated from patients and the 11 strains isolated from the Thai chickens showed high-level vancomycin resistance (MICs, 512 to 1,024 micro g/ml) and low-level teicoplanin resistance (MICs, 0.5 to 4 micro g/ml) . Each of these strains had three amino acid substitutions in the N-terminal region of the deduced VanS sequence . L50 was converted to V, E54 was converted to Q, and Q69 was converted to H compared to the vanS gene sequence of Tn1546.

J Int Med Res, 2002 Sep-Oct, 30(5), 529 - 34
A comparison of high-level aminoglycoside resistance in vancomycin-sensitive and vancomycin-resistant Enterococcus species; Yazgi H et al.; The aim of this study was to investigate whether there was a significant difference in high-level aminoglycoside resistance (HLAR) between vancomycin-sensitive enterococci (VSE) and vancomycin-resistant enterococci (VRE) . Vancomycin resistance was determined in 116 Enterococcus isolates using brain-heart infusion agar containing 6 micrograms/ml vancomycin . HLAR was determined by both standard agar screening and disk diffusion methods . Streptomycin and gentamicin were used as predictors of HLAR . Vancomycin resistance and HLAR were found in 17 (14.7%) and 41 (35.3%) of the Enterococcus strains, respectively . HLAR was found in 11 of 17 VRE and 30 of 98 VSE strains . HLAR in VRE strains was significantly higher than in VSE . More enterococcal strains were found to be resistant to both gentamicin and streptomycin (29) than to gentamicin (one) or streptomycin (11) alone . The HLAR rate in VRE was two-fold higher than in VSE . The synergistic bactericidal effect of aminoglycosides and beta-lactam or glycopeptide antibiotics is lost if there is high-level resistance to aminoglycosides.

Water Res, 2002 Dec, 36(20), 4963 - 74
Occurrence and levels of indicator bacteriophages in bathing waters throughout Europe; Contreras-Coll N et al.; Somatic coliphages, F-specific RNA bacteriophages, bacteriophages infecting Bacteroides fragilis, Escherichia coli and enterococci were counted in bathing waters in the late spring and summer . We tested fresh and marine bathing waters from North, South, East and West Europe expected to contain between 100 and 500 E . coli per 100 ml, although wider ranges were sometimes found . Bacteriophages were counted after concentration, since a preliminary study proved that this step was necessary to obtain positive counts . During monitoring, a first-line quality control with reference materials for bacteria and bacteriophages was performed by all the laboratories participating in the study . The same microbes were also counted in raw sewage samples from various areas in Europe, where the bacterial indicators and the three groups of bacteriophages were detected in roughly the same numbers . All groups of bacteriophages were detected in both fresh and marine bathing waters throughout Europe . Reliable and complete results from 147 samples showed that for log-transformed values, E . coli and bacteriophages were slightly correlated . However, the slope of the regression line changed according to E . coli concentration and the correlation diminished when this concentration was close to zero per 100 ml . The ratios between E . coli and phages in bathing waters differed significantly from those in sewage . The relative amounts of bacteriophages, mainly somatic coliphages and phages infecting Bact . fragilis RYC2056, increased in bathing waters with low E . coli concentration, especially in seawater samples containing < 100 E . coli per 100 ml . The relationship of bacteriophages with respect to enterococci paralleled that of bacteriophages with respect to E . coli . Somatic coliphages and bacteriophages infecting Bact . fragilis are useful to predict the presence of some pathogens with the same origin as present bacterial indicators but with higher survival rates.

Nippon Yakurigaku Zasshi, 2002 Oct, 120(4), 245 - 52
{Antimicrobial and clinical effect of linezolid (ZYVOX), new class of synthetic antibacterial drug}; Irinoda K et al.; Linezolid (ZYVOX), a novel synthesized antibacterial drug, was first approved in April 2001, as an antibacterial against vancomycin (VCM)--resistant enterococci in Japan . LZD has a wide spectrum of antibacterial activity against gram-positive bacteria with MIC90 of 0.5-4 mcg/mL . These antibacterial activities of LZD are similar to those of vancomycin (VCM) . LZD also has similar antibacterial activities against drug-resistant bacteria including VRE and MRSA . Protein-synthesis inhibitors, e.g., macrolides, tetracycline, aminoglycosides, and chloramphenicol, are known to bind the 30S and 50S subunits of ribosomes and inhibit the elongation cycle of protein synthesis . In contrast, LZD was found to inhibit the process of formation of the 50S, 30S-mRNA, and fMet-tRNA complex in the ribosome cycle, but not the elongation cycle . Due to this novel mechanism of action, LZD does not have a cross-resistance to drug-resistant bacteria and development of its resistance is quite slow . The antibacterial activity of LZD against VRE is bacteriostatic . In vivo antibacterial activity of orally administered LZD was demonstrated in a mouse model of systemic infection by VRE . When administered orally prior to the abscess formation in a mouse model of soft tissue infection by VRE, LZD showed similar antibacterial activity against VRE infection to that against VCM-susceptible enterococci . LZD is rapidly absorbed following oral administration and bioavailability when compared with intravenous administration is almost 100% . LZD administered orally twice-daily showed excellent efficacy in clinical trials with VRE-infected patients.

Int J Food Microbiol, 2003 Feb 25, 81(1), 1 - 10
Identification and antibiotic susceptibility of bacterial isolates from probiotic products; Temmerman R et al.; In the present study, a total of 55 European probiotic products were evaluated with regard to the identity and the antibiotic resistance of the bacterial isolates recovered from these products . Bacterial isolation from 30 dried food supplements and 25 dairy products, yielded a total of 268 bacterial isolates selected from several selective media . Counts of food supplements showed bacterial recovery in 19 (63%) of the dried food supplements ranging from 10(3) to 10(6) CFU/g, whereas all dairy products yielded growth in the range of 10(5)-10(9) CFU/ml . After identification of the isolates using whole-cell protein profiling, mislabeling was noted in 47% of the food supplements and 40% of the dairy products . In six food supplements, Enterococcus faecium was isolated whereas only two of those products claim this species on their label . Using the disc diffusion method, antibiotic resistance among 187 isolates was detected against kanamycin (79% of the isolates), vancomycin (65%), tetracycline (26%), penicillinG (23%), erythromycin (16%) and chloramphenicol (11%) . Overall, 68.4% of the isolates showed resistance against multiple antibiotics including intrinsic resistances . Initially, 38% of the isolated enterococci was classified as vancomycin resistant using the disc diffusion method, whereas additional broth dilution and PCR assays clearly showed that all E . faecium isolates were in fact vancomycin susceptible.

J Hosp Infect, 2002 Nov, 52(3), 206 - 11
Cleaning efficacy of nine different cleaners in a washer-disinfector designed for flexible endoscopes; Zuhlsdorf B et al.; Studies on processing endoscopes usually involve the combined cleaning and disinfecting activity . We compared nine cleaning agents designed for automatic processing for cleaning efficacy alone using soft and hard water as controls in 12 different processes in a washer-disinfector . Experiments were performed according to the German Endoscopy Working Group recommendations using transparent Teflon tubes (internal diameter 2mm, length 2m) as test pieces . For each test three pieces contaminated with a blood/test soil containing Enterococcus faecium were used; two for the test and one as a control; each test was repeated three times . Tests were run according to the manufacturer's instructions . Test pieces were assessed visually and microbiologically {log(10) reduction factors (RF) vs . untreated controls} . Soft water alone gave poor visible cleanliness and an RF of 0.3 (SD 0.2), while hard water produced adequate visible cleanliness and an RF of 1.2 (SD 1.0) . Five processes gave better visible cleanliness than soft water, but only three were better than hard water . Six processes were worse than soft water and five worse than hard water . Nine processes gave a better microbiological reduction factor than soft water, but the difference was only statistically significant in three . Only one process yielded a significantly higher RF than hard water; three were significantly worse . None of the cleaning processes reached the RF of 4 specified in the US regulations . This study confirms the variability of cleaning processes to dissolve blood residues and reduce the bioburden . We do not recommend abandoning cleaning agents, but suggest that further research is needed to clarify the relationships between washer-disinfectors, cleaning agents, and cleaning performance .

J Biochem (Tokyo), 2002 Nov, 132(5), 789 - 94
Nucleotide-binding sites in V-type Na+-ATPase from Enterococcus hirae; Murata T et al.; Enterococcus hirae V-ATPase, in contrast to most V-type ATPases, is resistant to N-ethylmaleimide (NEM) . Alignment of the amino acid sequences of NtpA suggests that the NEM-sensitive Cys of V-type ATPases is replaced by Ala in E . hirae V-ATPase . Consistent with this prediction, the V-ATPase became sensitive upon substitution of the Ala with Cys . The three-dimensional structure of the NtpB subunit of V-ATPase was modeled based on the structure of the corresponding subunit (alpha subunit) of bovine F(1)-ATPase by homology modeling . Overall, the 3D structure of the subunit resembled that of alpha subunit of bovine F(1)-ATPase . The NtpB subunit, which lacks the P-loop consensus sequence for nucleotide binding, was predicted to bind a nucleotide at the modeled nucleotide-binding site . Experimental data supported the prediction that the E . hirae V-ATPase had about six nucleotide-binding sites.

Rev Port Cardiol, 2002 Sep, 21(9), 989 - 99
Perioperative mortality and long-term outcome of infective endocarditis; Moura L et al.; INTRODUCTION AND OBJECTIVES: Infective endocarditis (IE) is a disease with a high morbidity and mortality during the active phase and a considerable risk of complications during follow-up . The aim of this study is to describe the clinical features of IE associated with perioperative mortality in patients undergoing surgery and the short- and long-term prognosis of this disease after surgical treatment . PATIENTS AND METHODS: The clinical files of 150 patients (pts) admitted to our institution between 1989 and 2001 and whose final diagnosis was IE (Duke criteria) were retrospectively reviewed . Thus all patients included underwent at least 1 transthoracic examination, and a transesophageal examination if indicated . The study population was 69 patients with IE, 62 of whom (90%) underwent prosthetic valve replacement and 7 (10%) underwent explanation of pacemaker electrocatheter . In the statistical analysis, quantitative variables are expressed as means +/- SD and qualitative variables as proportions (percentages) . Differences in survival were determined using the Kaplan-Meier log rank method . Associations were considered statistically significant when the p value was < 0.05 . RESULTS: The mean age was 56 +/- 15 years . Thirty-five cases (51%) had prosthetic valve endocarditis, 30 (39%) had native valve IE and 7 (10%) pacemaker electrocatheter IE . Fifty-two patients (75%) had positive blood cultures . The most frequent agents were S . epidermidis (14.5%), S . aureus (14.5%), Enterococci (13%) and S . viridans (10%) . Total perioperative mortality was 17.4% (n = 12), and surgical mortality was 19.4% . Our study shows a statistical tendency for higher mortality in diabetic patients (50% vs . 14%, p = 0.052) and in women (29% vs . 11%, p = 0.065) . In multivariate analysis, the presence of heart failure was an independent predictor of perioperative mortality (OR = 11.4; 95% CI: 2.0-215.2; p = 0.024) . Accumulated mortality in the first year was 28% and 5-year mortality was 48% . CONCLUSIONS: Prosthetic valve replacement in patients with IE is associated with high perioperative mortality (17.4%) . Despite good early postoperative results, the mortality rate increases during the first year as well as the need for reoperation.

Clin Infect Dis, 2002 Nov 15, 35(10), 1269 - 72 Epub 2002 Oct 28.
Risk factors associated with the development of infection with linezolid- and vancomycin-resistant Enterococcus faecium; Pai MP et al.; This retrospective cohort study revealed that linezolid resistance in vancomycin-resistant Enterococcus faecium was dependent on prior linezolid exposure and duration of linezolid therapy . These strains of E . faecium were resistant to the entire class of oxazolidinones.

Clin Infect Dis, 2002 Nov 15, 35(10), 1139 - 46 Epub 2002 Oct 17.
Risk factors for development of vancomycin-resistant enterococcal bloodstream infection in patients with cancer who are colonized with vancomycin-resistant enterococci; Zaas AK et al.; Vancomycin-resistant Enterococcus faecium (VRE) is a common nosocomial isolate, especially among patients with cancer . VRE infections have substantial attributable mortality among patients with cancer . The purpose of this study was to identify risk factors for developing bloodstream infection with VRE in patients with cancer who are colonized with VRE . VRE colonization was prospectively identified in 197 patients with cancer during 4-year period, of whom 179 (91%) had complete records for evaluation . Of these 179 patients, 24 (13.4%) developed hospital-acquired VRE bloodstream infections . Risk factors for VRE bloodstream infection included vancomycin use (relative risk {RR}, 1.98; 95% confidence interval {CI}, 1.25-3.14), diabetes mellitus (RR, 3.91; 95% CI, 1.20-12.77), gastrointestinal procedures (RR, 4.56; 95% CI, 1.05-19.7), and acute renal failure (RR, 3.10; 95% CI, 1.07-8.93) . Strategies for preventing VRE bloodstream infection in VRE-colonized patients with cancer should include limiting vancomycin use and, perhaps, gastrointestinal procedures.

Epidemiol Infect, 2002 Oct, 129(2), 421 - 4
Nucleotide substitutions in vanC-2 gene of Enterococcus casseliflavus isolates obtained from chickens; Murase T et al.; DNA sequencing of the vanC-2 gene was partially carried out on 10 isolates of Enterococcus casseliflavus obtained from 8 samples of imported chickens in Japan between July 1999 and June 2001 to evaluate the variation in the gene . Forty nucleotide substitutions in 36 codons were identified within 345 base pairs when compared with the vanC-2 sequence of the reference strain E . casseliflavus ATCC25788 . Identical nucleotide substitutions were commonly found in the isolates recovered from chickens imported from both Brazil and China . Pulsed-field gel electrophoresis (PFGE) patterns of NotI-digested chromosomal DNA of these strains were distinguished by two, or more than six, band differences . These observations suggest that sequencing of the vanC-2 gene may be helpful for epidemiological investigation in combination with the PFGE analyses of the isolates, although particular genotypes are unlikely to be restricted to each of the countries that exported chickens.

J Microbiol Methods, 2003 Jan, 52(1), 123 - 31
Application of the fluorogenic probe technique (TaqMan PCR) to the detection of Enterococcus spp . and Escherichia coli in water samples; Frahm E et al.; A recent PCR detection technique (TaqMan) based on the 5'-3'-exonuclease activity of the Taq DNA polymerase was applied to the detection of indicator organisms in water samples . In this technique, an increasing fluorescence signal is measured online which enables direct assessment of results after PCR without additional detection steps . The test is completed within about 5 h . Two sets of primers and probes were designed and tested: a genus-specific assay for the detection of Enterococcus spp . based on 23S rRNA sequence and an Escherichia coli-specific assay based on the uidA gene sequence . Specificity of the assays was confirmed by testing strains of target bacteria and potential interfering microorganisms . Application of the tests to 55 natural water samples showed the need of an overnight enrichment step to achieve compliance with detection limits of existing regulations . Compared with a parallel microbiological examination of the samples, agreement was 96% with the Enterococcus assay and 98% with the E . coli assay . The rapidity and feasibility of the method point to benefits in drinking water analysis, particularly in emergency situations and, thus, to improved public health management.

Fitoterapia, 2002 Oct, 73(6), 532 - 5
Antibacterial and antioxidant activities of Artemisia annua essential oil; Juteau F et al.; The essential oil of Artemisia annua aerial parts, consisting of camphor (44%), germacrene D (16%), trans-pinocarveol (11%), beta-selinene (9%), beta-caryophyllene (9%) and artemisia ketone (3%), was screened for its antimicrobial activity . The essential oil remarkably inhibited the growth of tested Gram-positive bacteria Enterococcus hirae and both tested fungi . This oil has shown an antioxidant activity equivalent to 18% of the reference compound (alpha-tocopherol) .

Antimicrob Agents Chemother, 2002 Nov, 46(11), 3676 - 8
Sequential emergence of antibiotic resistance in enterococcal bloodstream isolates over 25 years; Murdoch DR et al.; We determined the antibiotic susceptibilities of 1,785 enterococcal bloodstream isolates collected over 25 years . Antibiotic resistance emerged at a greater rate in Enterococcus faecium than in other enterococcal species, and E . faecium isolates became proportionally more common over time . Our findings confirm the pattern of emerging antibiotic resistance among enterococci and highlight the increasing importance of E . faecium as a cause of bloodstream infection.

Antimicrob Agents Chemother, 2002 Nov, 46(11), 3657 - 9
Mutations in ribosomal protein L16 and in 23S rRNA in Enterococcus strains for which evernimicin MICs differ; Zarazaga M et al.; Mutations in ribosomal protein L16 and in 23S rRNA were investigated in 22 Enterococcus strains of different species and for which the MICs of evernimicin differ (MICs, 0.023 to 16 micro g/ml) . Amino acid changes (Arg56His, Ile52Thr, or Arg51His) in protein L16 were found in seven strains, and a nucleotide G2535A mutation in 23S rRNA was found in 1 strain among 13 for which the MICs are > or =1 micro g/ml.

Infection, 2002 Oct, 30(5), 262 - 6
Glycopeptide use at four university hospitals in southern Germany; Kern WV et al.; BACKGROUND: Excessive use of glycopeptide antibiotics may enhance the risk of glycopeptide resistance among enterococci and staphylococi, but there is little data on the use of these antibiotics in German hospitals . METHODS: Hospital pharmacy records for the years 1992 to 1994 were evaluated . The number of defined daily doses (DDD) per 100 patient days was calculated to compare glycopeptide use between four state university hospitals . At one of the hospitals with comparatively low glycopeptide usage but an active antimicrobial management program, data were prospectively evaluated for 1995 to 2000 to assess the variation of glycopeptide use over time . RESULTS: The 3-year averages in glycopeptide use for the four hospitals ranged between 1.03 and 3.14 DDD/100 patient days . In all four hospitals, glycopeptide use was higher in the medical service (range, 1.59-7.26) than in the surgical service (range, 0.66-4.39) . Active antimicrobial management in one of the hospitals was associated with containment of glycopeptide consumption in the medical and surgical service at < 1.5 DDD/100 patient days in the last 3 years . CONCLUSION: Glycopeptide use differs considerably at tertiary care hospitals in southern Germany, but use of < 1.5 DDD/100 patient days in both surgical as well as medical tertiary care hospital departments appears achievable.

Int J Food Microbiol, 2003 Jan 25, 80(2), 145 - 52
Effect of enterococcin A 2000 on biological and synthetic phospholipid membranes; Pantev A et al.; Lactic acid bacterium isolated from Bulgarian cheese and identified as Enterococcus faecium produces a small hydrophobic peptide substance (enterococcin A 2000) with broad spectrum of antimicrobial activity . The wide range of enterococcin antibacterial activity of this compound against Gram-positive, as well as against some Gram-negative bacteria, suggests a single mechanism of action . The mode of action of enterococcin A 2000 was studied in intact liver mitochondria and synthetic phospholipid liposomes used as model systems . Enterococcin A 2000 stimulated the ATPase activity in intact mitochondria . The kinetic curve of ATP hydrolysis differed from that obtained in presence of dinitrophenol (DNP) and showed a character similar to the ATP hydrolysis in the presence of classic ionophores . Enterococcin A 2000, when bound to synthetic phospholipid liposomes, permeabilized liposomes liberating the marker carboxyfluorescein (CF).

Int J Food Microbiol, 2002 Dec 15, 79(3), 143 - 51
Vancomycin-resistant enterococci in shellfish, unchlorinated waters, and chicken; Wilson IG et al.; Vancomycin-resistant enterococci (VRE) have been a cause of increasing concern chiefly regarding the infection of hospital patients . There is suspicion, but limited evidence, that food and environmental spread may be important . Biomonitoring by examination of bivalve shellfish was used to assess the occurrence of VRE entering the environment . Using pre-enrichment and Lewisham and Slanetz and Bartley agars, 2/125 (1.6%) of shellfish were found to contain enterococci resistant to high levels of vancomycin . Lewisham agar allows relatively rapid identification of VRE . In a second phase of the work using pre-enrichment and Slanetz and Bartley agar, 4/151 (2.7%) shellfish and 5/27 (18.5%) raw chickens contained VRE . Using filtration and pre-enrichment, no VRE were found in 54 unchlorinated water samples . The study shows that environmental prevalence of VRE is low, and that raw chickens are frequently contaminated.

Acta Anaesthesiol Scand, 2002 Oct, 46(9), 1075 - 81
Antibiotic prescription practices, consumption and bacterial resistance in a cross section of Swedish intensive care units; Walther SM et al.; BACKGROUND: The purpose of this work was to study usage of antibiotics, its possible determinants, and patterns of bacterial resistance in Swedish intensive care units (ICUs) . METHODS: Prospectively collected data on species and antibiotic resistance of clinical isolates and antibiotic consumption specific to each ICU in 1999 were analyzed together with answers to a questionnaire . Antibiotic usage was measured as defined daily doses per 1000 occupied bed days (DDD1000) . RESULTS: Data were obtained for 38 ICUs providing services to a population of approximately 6 million . The median antibiotic consumption was 1257 DDD1000 (range 584-2415) and correlated with the length of stay but not with the illness severity score or the ICU category . Antibiotic consumption was higher in the ICUs lacking bedside devices for hand disinfection (2193 vs . 1214 DDD1000, p=0.05) . In the ICUs with a specialist in infectious diseases responsible for antibiotic treatment the consumption pattern was different only for use of glycopeptides (58% lower usage than in other ICUs: 26 vs . 11 DDD1000,P=0.02) . Only 21% of the ICUs had a written guideline on the use of antibiotics, 57% received information on antibiotic usage at least every 3 months and 22% received aggregated resistance data annually . Clinically significant antimicrobial resistance was found among Enterbacter spp . to cephalosporins and among Enterococcus spp . to ampicillin . CONCLUSIONS: Availability of hand disinfection equipment at each bed and a specialist in infectious diseases responsible for antibiotic treatment were factors that correlated with lower antibiotic consumption in Swedish ICUs, whereas patient-related factors were not associated with antibiotic usage.

Microb Drug Resist, 2002 Fall, 8(3), 161 - 70
Stability, persistence, and evolution of plasmid-encoded VanA glycopeptide resistance in enterococci in the absence of antibiotic selection in vitro and in gnotobiotic mice; Johnsen PJ et al.; Long-term persistence of VanA glycopeptide-resistant enterococci (GRE) has been observed in the absence of antibiotic selection . In the present study, we examined fitness parameters of a glycopeptide-susceptible Enterococcus faecium parent strain and its plasmid-mediated, VanA-resistant derivative before and after 1,000 generations in serial transfer broth cultures with or without antibiotic selection . With the exception of the vanA-containing plasmid, the strains were otherwise isogenic . The stability of the plasmid-encoded vanA resistance determinant was also investigated in vitro and in gnotobiotic mice . Competition experiments revealed that GRE with newly acquired VanA resistance had a 4% reduction in fitness relative to their susceptible parental counterpart . The relative difference in competitive fitness between resistant and susceptible strains was not significantly changed after 1,000 generations . Environmental adaptation was observed in all strains and exceeded the biological cost of resistance . Thus, the evolved VanA-resistant E . faecium populations out-numbered their unevolved ancestral susceptible E . faecium strain in mixed cultures, but remained less competitive than the evolved parent . The glycopeptide resistance determinant was similarly stably maintained during long-term colonization in gnotobiotic mice without antibiotic selection . In vivo vanA plasmid transfer was observed . The results suggest that environmental adaptation, in vivo gene transfer, and plasmid maintenance system(s) favor long-term VanA GRE persistence without antibiotic selection and compensate for the biological costs of possessing the resistance genes.

Clin Orthop, 2002 Oct, (403), 38 - 44
Osteomyelitis attributable to vancomycin-resistant enterococci; Holtom PD et al.; Vancomycin-resistant enterococcus first was described in 1988, and has become a major problem in nosocomial infections . This is a retrospective review of 10 patients, seen at the authors' hospital during a 2-year period, with confirmed vancomycin-resistant enterococcal osteomyelitis: four patients had total joint arthroplasty infections, one patient had an infected tibial nail, three patients had infections associated with external fixators, and two patients had osteomyelitis of the femur . Four of the 10 patients had underlying medical illnesses (diabetes mellitus, systemic lupus erythematosus, human immunodeficiency virus infection); four of the 10 patients were intravenous drug users . Two patients had vancomycin-resistant enterococci on admission, and the other eight patients were admitted to the hospital for a mean of 21.3 days (range, 3-73 days) before vancomycin-resistant enterococci were identified in the bone . Eight of the 10 patients had monomicrobial infections with vancomycin-resistant enterococci . Patients were treated by surgical debridement, removal of hardware, and antibiotics (chloramphenicol in eight patients, quinupristin and dalfopristin (Synercid) in two patients) . All patients initially improved with therapy, but one patient had a recurrence of vancomycin-resistant enterococcal osteomyelitis and died of bacteremia . Bone infections with vancomycin-resistant enterococcus still may be uncommon, but with time and selective antibiotic pressures, vancomycin-resistant enterococci may become a more prominent entity in orthopaedic infections.

J Antimicrob Chemother, 2002 Oct, 50(4), 569 - 76
Evaluation of antimicrobial therapy management of 120 consecutive patients with secondary peritonitis; Sotto A et al.; OBJECTIVES: To evaluate antimicrobial therapy management of secondary peritonitis in a University Hospital . PATIENTS AND METHODS: All patients admitted to the intensive care unit of the University Hospital of Nimes from 1 January 1997 to 31 July 1999 with a diagnosis of secondary peritonitis were retrospectively included . Patients' medical records were collected from the data recordings of the Department of Critical Care and Emergency and the Departments of Surgery . Acute Physiology and Chronic Health Evaluation II (APACHE II) was calculated for each patient at the time of admission . Antimicrobial treatment management before and after the diagnosis of peritonitis was studied . RESULTS: One hundred and twenty patients were included . Results concerning mortality, aetiology of peritonitis and microbiological data were in accordance with previous studies . APACHE II score (P = 0.005), age (P = 0.002), presence of Enterococcus in the peri-operative samples (P = 0.02) and period between diagnosis and surgery (P = 0.04) were predictive of death within 30 days after diagnosis of peritonitis . No significant difference was shown in the mortality rate in patients whose post-operative antibiotic treatment was changed following results of intra-operative peritoneal cultures versus patients having inappropriate treatment (P = 0.96) . The same observations were noted for anti-enterococcal treatment . CONCLUSION: This study emphasizes the importance of prompt surgical treatment and shows the modest impact of adapting antibiotic treatment . The morbidity and mortality associated with the presence of Enterococcus, which was not influenced by antibiotic treatment, would seem to suggest the pro-inflammatory role of Enterococcus . However, prospective randomized studies are needed to evaluate the real contribution of enterococcal antibiotic coverage in this context.

Clin Infect Dis, 2002 Oct 15, 35(8), 935 - 42 Epub 2002 Sep 19.
Effect of gastrointestinal bleeding and oral medications on acquisition of vancomycin-resistant Enterococcus faecium in hospitalized patients; Cetinkaya Y et al.; There has been minimal investigation of medications that affect gastrointestinal function as potential risk factors for the acquisition of vancomycin-resistant enterococci (VRE) . We performed a retrospective case-control study, with control subjects matched to case patients by time and location of hospitalization . Strict exclusion criteria were applied to ensure that only case patients with a known time of acquisition of VRE were included . Control patients were patients with > or =1 culture negative for VRE . The risk factors identified were use of vancomycin (odds ratio {OR}, 3.2; 95% confidence interval {CI}, 1.7-6.0; P=.0003), presence of central venous lines (OR, 2.2; 95% CI, 1.04-4.6; P=.04), and use of antacids (OR, 2.9; 95% CI, 1.5-5.6; P=.002) . Two protective factors included gastrointestinal bleeding (OR, 0.26; 95% CI, 0.08-0.79; P=.02) and use of Vicodin (Knoll Labs; hydrocodone and acetaminophen; OR, 0.93; 95% CI, 0.90-0.97; P=.0003) . Changes in gastrointestinal function, whether due to bleeding or to the effects of oral medications, may affect whether patients become colonized with VRE.

FEMS Microbiol Lett, 2002 Sep 10, 214(2), 159 - 63
Influence of growth media on vancomycin resistance of Enterococcus isolates and correlation with resistance gene determinants; Nayak R et al.; The effect of Mueller-Hinton (MH), MH+blood or brain heart infusion medium (agar or broth) on 13 Enterococcus isolates was determined, when testing their antibiotic susceptibility . Disk diffusion and Vitek methods were used to determine vancomycin resistance, while broth dilution and E-test methods were used to measure the minimum inhibitory concentration . The data were correlated with the presence of vancomycin resistance genes . A definite correlation pattern could not be established between the presence of van genes and vancomycin resistance in any plating medium, when tested by the disk diffusion assay . The broth dilution, irrespective of the plating medium, and Vitek methods were more reliable than the E-test method in testing isolates with vanA or vanB genes . However, for vanC2/C3 genotypes, the E-test method, irrespective of the plating medium, tested better than the broth dilution assay.

J Biol Chem, 2002 Nov 29, 277(48), 46779 - 84 Epub 2002 Sep 18.
RNase 7, a novel innate immune defense antimicrobial protein of healthy human skin; Harder J et al.; We analyzed healthy human skin for the presence of endogenous antimicrobial proteins that might explain the unusually high resistance of human skin against infections . A novel 14.5-kDa antimicrobial ribonuclease, termed RNase 7, was isolated from skin-derived stratum corneum . RNase 7 exhibited potent ribonuclease activity and thus may contribute to the well known ribonuclease activity of human skin . RNase 7 revealed broad spectrum antimicrobial activity against many pathogenic microorganisms and remarkably potent activity (lethal dose of 90% < 30 nm) against a vancomycin-resistant Enterococcus faecium . Molecular cloning from skin-derived primary keratinocytes and purification of RNase 7 from supernatants of cultured primary keratinocytes indicate that keratinocytes represent the major cellular source in skin and that RNase 7 is secreted . RNase 7 mRNA expression was detected in various epithelial tissues including skin, respiratory tract, genitourinary tract, and at a low level, in the gut . In addition to a constitutive expression, RNase 7 mRNA was induced in cultured primary keratinocytes by interleukin-1beta, interferon-gamma, and bacterial challenge . This is the first report demonstrating RNases as a novel class of epithelial inducible antimicrobial proteins, which may play an important role in the innate immune defense system of human epithelia.

Antimicrob Agents Chemother, 2002 Oct, 46(10), 3273 - 5
In vitro activity of the new oxazolidinone AZD2563 against Enterococci; Eliopoulos GM et al.; The activity of a new oxazolidinone antimicrobial, AZD2563, was assessed against >500 clinical isolates of enterococci representing six species . All isolates, including those resistant to other antibiotic classes, were inhibited by AZD2563 at concentrations </=2 micro g/ml, except for four strains resistant to linezolid . In most cases, AZD2563 was twofold more active than linezolid against enterococci.

Antimicrob Agents Chemother, 2002 Oct, 46(10), 3253 - 6
Mutations in the aph(2")-Ic gene are responsible for increased levels of aminoglycoside resistance; Lee HK et al.; Random PCR mutagenesis of the enterococcal aph(2")-Ic gene followed by selection for mutant enzymes that confer enhanced levels of aminoglycoside resistance resulted in mutants of APH(2")-Ic with His-258-Leu and Phe-108-Leu substitutions, all of which conferred rises in the MICs of several aminoglycosides . The mutated residues are located outside conserved regions of aminoglycoside phosphotransferases.

Antimicrob Agents Chemother, 2002 Oct, 46(10), 3125 - 32
Biochemical and genetic characterization of the vanC-2 vancomycin resistance gene cluster of Enterococcus casseliflavus ATCC 25788; Dutta I et al.; The vanC-2 cluster of Enterococcus casseliflavus ATCC 25788 consisted of five genes (vanC-2, vanXY(C-2), vanT(C-2), vanR(C-2), and vanS(C-2)) and shared the same organization as the vanC cluster of E . gallinarum BM4174 . The proteins encoded by these genes displayed a high degree of amino acid identity to the proteins encoded within the vanC gene cluster . The putative D,D-dipeptidase-D,D-carboxypeptidase, VanXY(C-2), exhibited 81% amino acid identity to VanXY(C), and VanT(C-2) displayed 65% amino acid identity to the serine racemase, VanT . VanR(C-2) and VanS(C-2) displayed high degrees of identity to VanR(C) and VanS(C), respectively, and contained the conserved residues identified as important to their function as a response regulator and histidine kinase, respectively . Resistance to vancomycin was expressed inducibly in E . casseliflavus ATCC 25788 and required an extended period of induction . Analysis of peptidoglycan precursors revealed that UDP-N-acetylmuramyl-L-Ala-delta-D-Glu-L-Lys-D-Ala-D-Ser could not be detected until several hours after the addition of vancomycin, and its appearance coincided with the resumption of growth . The introduction of additional copies of the vanT(C-2) gene, encoding a putative serine racemase, and the presence of supplementary D-serine in the growth medium both significantly reduced the period before growth resumed after addition of vancomycin . This suggested that the availability of D-serine plays an important role in the induction process.

Pediatr Infect Dis J, 2002 Aug, 21(8), 798 - 800
Linezolid treatment of vancomycin-resistant Enterococcus faecium ventriculitis; Graham PL et al.; The successful treatment of a 7-month-old infant with shunt-associated ventriculitis caused by vancomycin-resistant Enterococcus faecium is presented . Linezolid was administered intravenously every 8 h; children have a greater volume of distribution and total body clearance than adults and therefore require more frequent dosing . The patient tolerated the therapy without adverse effects.

Perit Dial Int, 2002 May-Jun, 22(3), 339 - 44
Comparison of vancomycin versus cefazolin as initial therapy for peritonitis in peritoneal dialysis patients; Khairullah Q et al.; The incidence of peritonitis ranges from 1 episode every 24 patient treatment months to 1 episode every 60 patient treatment months {Keane WF, et al . ISPD Guidelines/Recommendations . Adult peritoneal dialysis-related peritonitis treatment recommendations: 2000 update . Perit Dial Int 2000; 20:396-411.} . Gram-positive organisms account for over 80% of continuous ambulatory peritoneal dialysis (PD)-associated peritonitis . Recent fear of vancomycin-resistant enterococci (VRE) has prompted suggestions of limiting vancomycin use . Fifty-one episodes of peritonitis in 30 patients studied over 2 years were evaluated . Cloudiness of the PD fluid and/or abdominal pain were considered suggestive of peritonitis and were confirmed by cell count and culture . Baseline cell count, Gram stain, and cultures were obtained, with periodic follow-up . Patients were randomized to receive either vancomycin 1 g/L intraperitoneally (IP) as loading dose, repeated on day 5 or day 8, depending on residual renal function, for 2 weeks, or cefazolin 1 g in the first PD bag and continued with 125 mg/L every exchange for 2 or 3 weeks, depending on culture results . All patients also received gentamicin 40 mg IP every day until the culture results were available . A similar randomized trial comparing vancomycin and cefazolin in the past used a lower concentration of cefazolin 50 mg/L {Flanigan MJ, Lim VS . Initial treatment of dialysis associated peritonitis: a controlled trial of vancomycin versus cefazolin . Perit Dial /nt 1991; 11:31-7.} . Peritoneal dialysate fluid cultures revealed 31(60.7%) gram-positive organisms, 7(13.7%) gram-negative organisms, and 2 (3.9%) cultured yeast; 11 (21.5%) cultures yielded no growth . The incidence of peritonitis at our center was 1 episode every 42 patient treatment months . No case of VRE was noted . There was no statistical difference in clinical response or relapse rate for the two protocols . It was the authors' and nurses' observation that patient compliance and satisfaction was better with vancomycin, and the cost per treatment was 23% less than cefazolin . Based on these data we believe vancomycin should still be considered for first-line treatment of PD-associated peritonitis.

Biosci Biotechnol Biochem, 2002 Jul, 66(7), 1597 - 600
Isolation of Enterococcus hirae mutant deficient in low-affinity potassium uptake at alkaline pH; Kawano M et al.; We here isolated an Enterococcus hirae mutant unable to grow well at pH 10 . The influx rate calculated from steady-state 42K+/K+ exchange and the intracellular K+ concentration of the mutant were reduced to 53 and 55% of those of the wild-type, respectively . The activities of two high-affinity K+ uptake systems, KtrI and KtrII, were normal in the mutant, but the kinetics of net K+ uptake at pH 10 indicated that a low-affinity K+ uptake with a Km of about 20 mM (Kawano, M, Abuki, R, Igarashi, K, Kakinuma, Y . (2001) Arch . Microbiol . 175: 41-45), which were seen in the wild-type, was deficient in this mutant.

Epidemiol Infect, 2002 Aug, 129(1), 57 - 64
The epidemiology of glycopeptide-resistant enterococci on a haematology unit--analysis by pulsed-field gel electrophoresis; Bradley SJ et al.; As part of an interventional study to determine glycopeptide-resistant enterococci (GRE) acquisition on a three-ward haematology unit, rectal swabs were taken weekly from 293 patients recruited to the study between June 1995 and December 1996 . The GRE isolates obtained from the first positive rectal swab from 120 colonized patients, the isolates from 7 patients with clinical infection and 43 isolates obtained from the ward environment were compared by pulsed-field gel electrophoresis (PFGE) . Sixty-three of 120 patients were colonized by one of strains A-H, while 49 were colonized by unique strains . The first 18 weeks were associated with the highest prevalence of GRE by rectal swab, with a single strain A responsible for 52% of acquisitions on ward 2, 22% on ward 3 and 36% on ward 4 . Other smaller ward associated clusters were evident . Environmental sampling of ward 2 during this time showed that all but 2 of 30 isolates were indistinguishable from strain A . As the GRE prevalence fell, rectal swab and environmental isolates became more heterogeneous, and strain A disappeared after week 55 . GRE prevalence rose again in the final 15 weeks of the study, and a new predominant strain B emerged on ward 2 responsible for 50% of new acquisitions . In the seven patients with clinical infection with GRE, the clinical isolates were compared with the contemporaneous rectal swab isolate, and were found to be the same in only two cases . An analysis of five long-term carriers colonized for a median of 19 weeks (range 11-34) showed colonization with at least two and in one case six distinct strains, raising the question of how many strains may be colonizing a patient at any one time, and suggesting that multiple colonies should be analysed . These data suggest that cross-infection was an important factor in the spread of GRE when the colonization rate was high.

J Antimicrob Chemother, 2002 Sep, 50(3), 397 - 401
First outbreak of vancomycin-resistant enterococci in a tertiary hospital in Turkey; Colak D et al.; Twenty multidrug-resistant vancomycin-resistant Enterococcus faecium strains of the VanA phenotype were isolated over a 1 year period from five patients in the intensive care unit at the University Hospital of Antalya, Turkey . Molecular investigation showed that these strains belonged to five different pulsotypes and that the vanA gene was carried by a Tn1546-like transposon inserted onto a self-transferable plasmid of approximately 200 kb . One patient was infected by two different strains, suggesting horizontal gene transfer within that patient . This is the first documented outbreak of VRE in Turkey with concomitant spread of plasmid and strains.

Biochem Soc Trans, 2002 Aug, 30(4), 688 - 91
Role of proteolysis in copper homoeostasis; Solioz M; The cop operon of Enterococcus hirae controls cytoplasmic copper levels . It encodes two copper ATPases, a repressor, and the CopZ metallochaperone . Transcription of these genes is induced by copper . However, at higher copper concentrations, CopZ is degraded by a copper-activated proteolytic activity . This specific proteolysis of CopZ can also be demonstrated in vitro with E . hirae extracts . Growth of the cells in copper increases the copper-inducible proteolytic activity in extracts . Zymography reveals the presence of a copper-dependent protease in crude cell lysates . Copper-stimulated proteolysis of CopZ appears to play an important role in copper homoeostasis by E . hirae.

Emerg Infect Dis, 2002 Sep, 8(9), 961 - 5
First characterization of a cluster of VanA-type glycopeptide-resistant Enterococcus faecium, Colombia; Panesso D et al.; From August 1998 to October 1999, glycopeptide-resistant enterococci (GRE) were isolated from 23 infected patients at a teaching hospital in Medellin, Colombia . Identification at the species level and by multiplex polymerase chain reaction assay indicated that all isolates were Enterococcus faecium . The isolates were highly resistant to ampicillin, ciprofloxacin, gentamicin, penicillin, streptomycin, teicoplanin, and vancomycin; they were susceptible only to chloramphenicol, linezolid, and nitrofurantoin . Determination of glycopeptide genotype indicated the presence of the vanA gene in all isolates . Molecular typing by pulsed field gel electrophoresis showed that all isolates were closely related . This study is the first molecular characterization of GRE in Colombia.

Arch Microbiol, 2002 Sep, 178(3), 172 - 9 Epub 2002 Jun 20.
Promoter analysis of the sodium-responsive V-ATPase (ntp) operon in Enterococcus hirae; Yasumura K et al.; The Enterococcus hirae ntp operon encodes all subunits of the vacuolar-type ATPase (V-ATPase), which transports Na(+) or Li(+) . This operon is expressed preferentially in response to Na(+), but not to Li(+) . Deletion analysis of the ntp promoter region in plasmids indicated that the AT-tract between -198 and -132 is required for Na(+)-specific transcriptional regulation . In addition, lithium-tolerant (LTR) mutants were isolated in which functional V-ATPase levels were high even in Na(+)-depleted medium . Western blot and Northern blot experiments revealed an increase in basal Na(+)-independent transcription in one of the mutants (LTR1) . The nucleotide sequences of the ntp promoter region of the LTR mutants showed mutational conversion of single base-pairs between positions -23 and +1 . Na(+)-independent expression of a reporter gene linked to the ntp promoter in plasmids was elevated by base substitutions at -23 to +1, and promoter activity induced by these base substitutions was lost by deletion of the region between -198 and -132 . These results suggest that the AT-tract between -198 and -132 is indispensable for transcription of the ntp operon.

Infect Control Hosp Epidemiol, 2002 Aug, 23(8), 471 - 4
Impact of infection by vancomycin-resistant Enterococcus on survival and resource utilization for patients with leukemia; Bach PB et al.; We estimated the impact of vancomycin-resistant Enterococcus (VRE) infection on the outcomes of patients with leukemia in a case-control study . Compared with their matched controls (n = 45), cases (n = 23) had 22% greater total charges and shorter survival (P = .04) . These findings substantiate the need for aggressive interventions to prevent VRE transmission.

Infect Control Hosp Epidemiol, 2002 Aug, 23(8), 468 - 70
An outbreak of vancomycin-resistant enterococci in a hematology-oncology unit: control by patient cohorting and terminal cleaning of the environment; Sample ML et al.; We describe the impact of enhanced infection control interventions on controlling the spread of vancomycin-resistant enterococci (VRE) in our hematology-oncology unit . Between April and September 1998, 13 patients on this unit were identified as having VRE . In addition to contact precautions, other measures that were needed to control the outbreak included closure of the unit to new admissions, creation of a cohort of VRE-positive patients and staff, and thorough cleaning of patients' rooms with 0.5% sodium hypochlorite.

Infect Control Hosp Epidemiol, 2002 Aug, 23(8), 436 - 40
Recurrence of vancomycin-resistant Enterococcus stool colonization during antibiotic therapy; Donskey CJ et al.; OBJECTIVE: To test the hypothesis that antibiotic therapy may promote recurrence of vancomycin-resistant Enterococcus (VRE) stool colonization in patients who have previously had three consecutive negative stool cultures obtained at least 1 week apart . DESIGN: One-year prospective cohort study examining the effect of antibiotic therapy on recurrence and density of VRE stool colonization in patients who have cleared colonization . Pulsed-field gel electrophoresis (PFGE) was performed to determine whether recurrent VRE strains were the same clone as the previous colonizing strain . SETTING: A Department of Veterans Affairs medical center including an acute care hospital and nursing home . PATIENTS: All patients with at least one stool culture positive for VRE who subsequently had three consecutive negative stool cultures obtained at least 1 week apart . RESULTS: Of the 16 patients who cleared VRE colonization, 13 received antibiotic therapy during the study period . Eight (62%) of the 13 patients who received antibiotics developed recurrent high-density VRE stool colonization (range, 4.9 to 9.1 log10 colony-forming units per gram) during a course of therapy . Five patients had VRE strains available for PFGE analysis; recurrent strains were unrelated to the prior strain in 3 patients, closely related in 1 patient, and indistinguishable in 1 patient . CONCLUSIONS: Antibiotic therapy may be associated with recurrent high-density VRE stool colonization in many patients who have previously had three consecutive negative stool cultures . These patients should be screened for recurrent stool colonization when antibiotic therapy is administered.

Infect Control Hosp Epidemiol, 2002 Aug, 23(8), 429 - 35
Cost-effectiveness of perirectal surveillance cultures for controlling vancomycin-resistant Enterococcus; Muto CA et al.; BACKGROUND: Several hospitals opting not to use active surveillance cultures to identify carriers of vancomycin-resistant Enterococcus (VRE) have reported that adoption of other parts of the Centers for Disease Control and Prevention guideline for controlling VRE has had little to no impact . Because use of surveillance cultures and contact isolation controlled a large outbreak at this hospital, their costs were estimated for comparison with the excess costs of VRE bacteremias occurring at a higher rate at a hospital not employing these measures . SETTING: Two university hospitals . METHODS: Inpatients deemed high risk for VRE acquisition at this hospital underwent weekly perirectal surveillance cultures . Estimated costs of cultures and resulting isolation during a 2-year period were compared with the estimated excess costs of more frequent VRE bacteremias at another hospital of similar size and complexity not using surveillance cultures to control spread throughout the hospital . RESULTS: Of 54,052 patients admitted, 10,400 had perirectal swabs taken . Cultures and isolation cost an estimated $253,099 . VRE culture positivity was limited to 193 (0.38%) and VRE bacteremia to 1 (0.002%) as compared with 29 bacteremias at the comparison hospital . The estimated attributable cost of VRE bacteremia at the comparison hospital of $761,320 exceeded the cost of the control program at this hospital by threefold . CONCLUSIONS: The excess costs of VRE bacteremia may justify the costs of preventive measures . The costs of VRE infections at other body sites, of deaths from untreatable infections, and of dissemination of genes for vancomycin resistance also help to justify the costs of implementing an effective control program.

Infect Control Hosp Epidemiol, 2002 Aug, 23(8), 424 - 8
A prospective study to determine whether cover gowns in addition to gloves decrease nosocomial transmission of vancomycin-resistant enterococci in an intensive care unit; Srinivasan A et al.; BACKGROUND: Vancomycin-resistant enterococci (VRE) remain a significant nosocomial pathogen . Current guidelines of the Hospital Infection Control Practices Advisory Committee (HICPAC) of the Centers for Disease Control and Prevention (CDC) recommend the use of gowns and gloves for some interactions with VRE-infected or -colonized patients to prevent nosocomial transmission of VRE . OBJECTIVE: To assess the effect of disposable cover gowns on preventing nosocomial transmission of VRE . DESIGN AND SETTING: Prospective study in a 16-bed medical intensive care unit of a university teaching hospital . PATIENTS: All patients who were at risk to acquire VRE, were admitted to the intensive care unit from August 1998 to January 1999, and had at least two perirectal cultures were included in the analysis of VRE acquisition . INTERVENTION: VRE isolation precautions were changed from gowns and gloves to gloves alone . MAIN OUTCOME risk factors for VRE acquisition . RESULTS: The VRE acquisition rate was 1.80 cases per 100 days at risk in the gown and gloves period compared with 3.78 in the gloves only period (P = .04) . In a proportional hazards model adjusted for length of stay, gloves only precautions with a hazard ratio of 2.5 (P = .02; 95% confidence interval, 1.2 to 5.3) were the only independent risk factor for VRE acquisition . CONCLUSION: Our data lend support to current HICPAC recommendations for the use of cover gowns to decrease nosocomial transmission of VRE.

Antimicrob Agents Chemother, 2002 Sep, 46(9), 3088 - 90
Incidence of high-level evernimicin resistance in Enterococcus faecium among food animals and humans; Aarestrup FM et al.; Six high-level evernimicin-resistant Enterococcus faecium isolates were identified among 304 avilamycin-resistant E . faecium isolates from animals and 404 stool samples from humans with diarrhea . All four animal isolates, and one of the human isolates, were able to transfer resistance to a susceptible E . faecium strain . The resulting transconjugants all tested positive for the presence of emtA, a gene encoding a methyltransferase previously linked with high-level evernimicin resistance . The four transconjugants derived from animal isolates all carried the same plasmid, while a differently sized plasmid was found in the isolate from humans . This study demonstrated a low incidence of high-level evernimicin resistance mediated by the emtA gene in different E . faecium isolates of animal and human origin.

J Antimicrob Chemother, 2002 Aug, 50(2), 253 - 6
Association between the vanB2 glycopeptide resistance operon and Tn1549 in enterococci from France; Umeda A et al.; Linkage between the vanB2 gene cluster and transposon Tn1549 was found in clonally unrelated VanB-type vancomycin-resistant Enterococcus spp . strains isolated in France . The transposon was chromosomally located or plasmid borne.

Scand J Infect Dis, 2002, 34(6), 471 - 2
Enterococcus casseliflavus septicaemia in a preterm neonate; Ruess M et al.; Enterococcus casseliflavus is a yellow-pigmented, motile, Gram-positive coccus that is only rarely isolated from clinical specimens . We report the first case of neonatal sepsis due to E . casseliflavus in a premature neonate . Precise identification of Enterococcus species is difficult but is of significant clinical interest because of the intrinsic low-level resistance to vancomycin of species such as E . casseliflavus and E . gallinarum.

Presse Med, 2002 Jun 8, 31(20), 933 - 4
{Enterococcal meningitis revealing endocarditis}; Tonnellier M et al.; INTRODUCTION: Enterococci are frequently responsible for endocarditis, but a rare cause of meningitis . OBSERVATION: A 55 years-old man presented with Enterococcus faecium meningitis . Systematic transoesophageal echocardiography (TOE), despite the absence of organic murmur and the negativity of the hemocultures, revealed a concomitant aortic endocarditis . CONCLUSION: Review of the literature suggests that the association of endocarditis with enterococcal meningitis is far from accidental . We suggest that a TOS be conducted systematically when faced with this disease . The therapeutic implications are important, notably regarding the duration of antibiotherapy.

Appl Environ Microbiol, 2002 Aug, 68(8), 4127 - 9
Antimicrobial resistance among enterococci from pigs in three European countries; Aarestrup FM et al.; Enterococci from pigs in Denmark, Spain, and Sweden were examined for susceptibility to antimicrobial agents and copper and the presence of selected resistance genes . The greatest levels of resistance were found among isolates from Spain and Denmark compared to those from Sweden, which corresponds to the amounts of antimicrobial agents used in food animal production in those countries . Similar genes were found to encode resistance in the different countries, but the tet(L) and tet(S) genes were more frequently found among isolates from Spain . A recently identified transferable copper resistance gene was found in all copper-resistant isolates from the different countries.

Zh Mikrobiol Epidemiol Immunobiol, 2002 May-Jun, (3), 100 - 6
{Mechanisms of enterococcal survival in the host}; Bukharin OV et al.; Information on virulence and persistence factors of enterococci as important nosocomial pathogens with ever increasing multiple drug resistance is updated . The importance of the virulent and persistent properties of enterococci in the processes of adhesion to host tissues, invasion, modulation of inflammatory responses, as well as their toxic action on the host body is considered . The pathogenicity factors of enterococci are relevant to the mechanisms of the bacterial survival in the host.

J Mol Microbiol Biotechnol, 2002 Jul, 4(4), 357 - 65
Bacterial bioinformatics: pathogenesis and the genome; Paine K et al.; As the number of completed microbial genome sequences continues to grow, there is a pressing need for the exploitation of this wealth of data through a synergistic interaction between the well-established science of bacteriology and the emergent discipline of bioinformatics . Antibiotic resistance and pathogenicity in virulent bacteria has become an increasing problem, with even the strongest drugs useless against some species, such as multi-drug resistant Enterococcus faecium and Mycobacterium tuberculosis . The global spread of Human Immunodeficiency Virus (HIV) and Acquired Immune Deficiency Syndrome (AIDS) has contributed to the re-emergence of tuberculosis and the threat from new and emergent diseases . To address these problems, bacterial pathogenicity requires redefinition as Koch's postulates become obsolete . This review discusses how the use of bacterial genomic information, and the in silico tools available at present, may aid in determining the definition of a current pathogen . The combination of both fields should provide a rapid and efficient way of assisting in the future development of antimicrobial therapies.

Microb Drug Resist, 2002 Summer, 8(2), 133 - 8
Vancomycin-resistant enterococci (VRE) in broiler flocks 5 years after the avoparcin ban; Heuer OE et al.; The glycopeptide growth promoter avoparcin was banned from animal production in Denmark in 1995 . In this study, we investigated the occurrence of vancomycin-resistant enterococci (VRE) in broiler flocks in the absence of the selective pressure exerted by the use of avoparcin . One hundred sixty-two broiler flocks from rearing systems with different histories of avoparcin exposure were investigated for the presence of VRE . Using a direct selective plating procedure, VRE were isolated from 104 of 140 (74.3%) broiler flocks reared in broiler houses previously exposed to avoparcin on conventional and extensive indoor broiler farms . In contrast, only 2 of 22 (9.1%) organic broiler flocks reared on free-range farms with no history of previous exposure to avoparcin were VRE-positive . Furthermore, the occurrence of VRE over time in flocks reared in broiler houses previously exposed to avoparcin was investigated . Results obtained by direct selective plating showed no significant decrease in the proportion of VRE-positive flocks during the study period (1998-2001) . This study demonstrated the extensive occurrence of VRE in broiler flocks more than 5 years after the avoparcin ban in Denmark, and indicates that VRE may persist in the absence of the selective pressure exerted by avoparcin . The results differ markedly from previously published Danish surveillance data on VRE in broilers . This may reflect differences in isolation procedures.

Intensive Care Med, 2002 Jun, 28(6), 692 - 7 Epub 2002 Apr 12.
Vancomycin-sensitive and vancomycin-resistant enterococcal infections in the ICU: attributable costs and outcomes; Pelz RK et al.; OBJECTIVES: To determine the economic and clinical outcomes associated with infection with vancomycin-resistant Enterococcus (VRE) and to compare these outcomes to those associated with infection with vancomycin-sensitive Enterococcus (VSE) . METHODS: During a 3-month, prospective, cohort study of 117 high-risk, critically ill patients we collected complete clinical and demographic and ICU cost data from all patients during their ICU stays . RESULTS: After adjusting for variables in a stepwise multiple regression model VRE infections were associated with a median attributable increased ICU cost per patient of $33,251 (38,088 euros) and an increased length of hospital stay (LOS) of 22 days, while VSE infections were associated with an increased cost of $21,914 (25,102 euros) and an increased LOS of 27 days . The effect of VRE and VSE infections were not significantly different . Over the entire cohort the attributable cost per ICU patient day associated with VRE infection was $304 (348 euros) . CONCLUSIONS: The attributable cost of ICU care associated with VRE infection is $33,251 (38,088 euros) and per ICU patient day was $304 (348 euros) . VRE and VSE infections do not differ in associated cost of ICU care, LOS, or mortality . Any VRE control strategy is be cost-effective if the overall cost per ICU patient-day is less than $304 (348 euros).

Diagn Microbiol Infect Dis, 2002 Jul, 43(3), 183 - 8
Risk factors for acquisition of vancomycin-resistant enterococci among hematology-oncology patients; Suntharam N et al.; The incidence of VRE has increased dramatically and hematology-oncology patients are at high risk for acquisition of colonization and development of infection . Therefore, we performed a prospective cohort study to determine risk factors for VRE acquisition among hematology-oncology patients . Patients admitted to a single unit at Northwestern Memorial Hospital, which was predominantly comprised of patients with hematologic malignancies and recipients of hematopoietic stem cell transplants, were enrolled . Rectal or perianal swabs were obtained on hospital day 1, 4, 7 and then weekly thereafter . Data were collected by medical record review . We evaluated 155 study patients; 12 patients (7.7%) converted from VRE negative to positive . Among these 12 patients, 3 were positive on prior admissions, and 9 acquired VRE during the study . The median time to acquisition was 9 days . The median length of stay was significantly longer for patients with VRE compared to those who were VRE negative (31 vs . 6 days, P < 0.01) . Patients with VRE were significantly more likely than those without VRE to have had an ICU admission within 3 months (P = 0.003), been admitted from an acute care facility (P = 0.001), or to have received amikacin (P = 0.02) . Antimicrobials were commonly prescribed to all of the patients as 87% received an antimicrobial prior to their first swab . The crude mortality rate for patients with VRE was 67% . Prolonged length of stay, prior hospitalization, previous ICU admission and receipt of amikacin were risk factors associated with VRE acquisition among hematology-oncology patients . Mortality among these patients was high, due to serious underlying disease.

Semin Dial, 2002 May-Jun, 15(3), 162 - 71
National surveillance of dialysis-associated diseases in the United States, 2000; Tokars JI et al.; In December 2000, all U.S . dialysis centers were surveyed regarding selected patient care practices and dialysis-associated diseases . The results were compared with similar surveys conducted in previous years . During 1997-2000, the percentage of patients vaccinated against hepatitis B virus infection increased from 47% to 58% and the percentage of staff vaccinated increased from 87% to 88% . In 2000, an estimated 64% of patients were vaccinated for influenza and 27% for pneumococcal pneumonia . In 2000, routine testing for antibody to hepatitis C virus (anti-HCV) was performed on staff at 40% of centers and on patients at 58% of centers; anti-HCV was found in 1.7% of staff and 8.4% of patients . During 1995-2000, the percentage of patients who received dialysis through central catheters increased from 13% to 24%; this trend is worrisome because infections and antimicrobial use are higher in patients receiving dialysis through catheters . However, during the same period the percentage of patients receiving dialysis through fistulas increased from 22% to 28% . In 2000, 25% of catheters were used for new patients awaiting an implanted access, 28% for established patients with a failed access awaiting a new implanted access, 41% as an access of last resort, and 6% for other reasons, including patient preference . The percentage of centers reporting one or more patients infected or colonized with vancomycin-resistant enterococcus (VRE) increased from 11.5% in 1995 to 32.7% in 2000.

Arch Phys Med Rehabil, 2002 Jul, 83(7), 899 - 902
Patient colonization and environmental contamination by vancomycin-resistant enterococci in a rehabilitation facility; Trick WE et al.; OBJECTIVES: To determine the frequency of environmental contamination in patient and common-use rooms and patient colonization by vancomycin-resistant enterococci (VRE) . DESIGN: Cross-sectional study . SETTING: A 146-bed rehabilitation facility . PARTICIPANTS: Rectal cultures were collected from 74 (80%) of 93 patients . Environmental cultures were obtained from surfaces in 15 patient rooms (5 floors) and common-use areas on 8 floors . INTERVENTIONS: Not applicable . MAIN OUTCOME MEASURES: Gastrointestinal colonization of patients and environmental contamination of surfaces by VRE . RESULTS: VRE was detected from 13 (18%) of 74 patients and 32 (10%) of 319 surfaces . The frequency of positive environmental cultures varied by location; cultures were more likely to be positive in patient rooms (15%), followed by common areas on patient floors (9%) and common areas separate from patient floors (1.3%) . Surfaces were more likely to be positive in rooms with a VRE-colonized patient (24%), compared with rooms in which patient colonization status was unknown (13%, P=.13) or the patient was not colonized (0%, P=.002) . Surfaces were more likely to be contaminated in a room that housed an incontinent compared with continent patients (22% vs 7%, P=.01) . CONCLUSIONS: Although environmental contamination by VRE was common in patient rooms, contamination of common-use areas separate from patient floors was infrequent . Despite use of common-use areas by colonized patients, isolation practices at this facility appear to have minimized environmental surface contamination in these areas .

J Vasc Surg, 2002 Jul, 36(1), 180 - 3
Stent graft infection after abdominal aortic aneurysm repair: a case report; Baker M et al.; A 77-year-old man had clinical and radiologic signs of graft infection develop 1 year after stent grafting for abdominal aortic aneurysm . Blood cultures grew Bacteroides fragilis, and cultures of the aneurysm sac grew Enterococcus . The patient's condition was successfully managed with staged extraanatomic revascularization followed by graft excision . Although stent graft infection to date is extremely rare, some aspects peculiar to the placement of these devices potentially could increase their susceptibility to infection . Recognition and standard techniques in management can lead to successful outcome.

Planta Med, 2002 Jun, 68(6), 541 - 3
Antibacterial activity of calozeyloxanthone isolated from Calophyllum species against vancomycin-resistant Enterococci (VRE) and synergism with antibiotics; Sakagami Y et al.; Calozeyloxanthone ( 1) was re-isolated from the root bark of Calophyllum moonii, an endemic species of Sri Lanka, and found to be active against vancomycin-resistant Enterococci (VRE) and vancomycin-sensitive Enterococci (VSE) with MIC values of 6.25 microg/ml and 12.5 microg/ml, respectively . Further, a marked synergism between 1 and vancomycin hydrochloride (VCM) against VRE was also observed . These findings suggest that 1 in combination with VCM against VRE may be useful in controlling VRE infections.

J Am Soc Echocardiogr, 2002 Jul, 15(7), 702 - 7
Better prognosis of elderly patients with infectious endocarditis in the era of routine echocardiography and nonrestrictive indications for valve surgery; Zamorano J et al.; OBJECTIVE: It has been reported that endocarditis in the elderly may have a poor outcome . Our aim was to assess the different features and prognosis, if any, in the present time . METHODS: Of 103 patients with proven endocarditis, 31 were 65 years or older and 72 were younger than 65 years . Degenerative heart disease was seen more frequently in the elderly (22.5% vs 2.7%, P =.003) . Drug abuse and immunodeficiency virus infection were more common in the younger group, as was tricuspid endocarditis (26.3% vs 0%, P <.001) . At clinical presentation cardiac failure (41.9 vs 19.4%, P =.02) and leukocytosis (61.2% vs 40.2%, P =.049) were seen more frequently in the elderly . RESULTS: Despite other similar clinical features, it took longer to diagnose older patients (7.2 +/- 6.2 vs 3.2 +/- 3.5 days, P <.001) . Enterococcus infected the aged more often (32.2% vs 13.1%, P =.001) . During hospitalization, heart failure and embolization tended to be more common in the elderly and the younger group, respectively . There were no significant differences in the incidence of anatomic complications, the need for operation, and overall mortality . CONCLUSION: Although a worse prognosis has been reported in elderly patients with infective endocarditis, the early use of transesophageal echocardiographic examinations and equal therapeutic options provides a similar outcome when compared with younger subjects.

J Clin Microbiol, 2002 Jul, 40(7), 2689 - 90
Native valve endocarditis due to Enterococcus hirae; Poyart C et al.; Enterococcus hirae is a rare isolate in clinical specimens . We describe a case of native aortic-valve endocarditis that was caused by Enterococcus hirae in a 72-year-old man . This is the first reported case of endocarditis due to this organism.

Contemp Top Lab Anim Sci, 1999 Nov, 38(6), 39 - 41
Pyometra in a Siberian Polecat (Mustela eversmanni); Johnson JD et al.; A 2-year-old Siberian polecat (Mustela eversmanni) from a breeding colony presented for ultrasound evaluation for pregnancy . It was paired with a male for 2.75 months and had remained absent of pregnancy signs when it was anesthetized and clinically evaluated . Until this time, the animal had eaten well and shown no outward signs of debility . On palpation, the animal had a fluid-filled tubular structure in the caudal abdomen, consistent in location and size with the uterus . No sign of vaginal discharge was present . Ultrasonography revealed 10 fluid-filled evaginations (approximately 12 mm in diameter) of the uterine horns . A presumptive diagnosis of a fluid-filled reproductive tract and likely reproductive failure was made in light of the animal's history, its clinical signs, and the ultrasound findings . Euthanasia was performed because the animal was nonreproductive and might yield information relevant to the breeding colony as a whole . Necropsy of the polecat revealed a distended fluctuant uterus containing mildly odiferous, thick, yellow-green, purulent material . Histopathology confirmed the diagnosis of pyometra . A pure and heavy growth of Enterococcus fecalis was cultured from the uterine contents . In light of results from routine minimal inhibitory concentration antibiotic sensitivity screening, this isolate was resistant to all antibiotics tested in the standard teaching hospital screen.

Clin Nephrol, 2002 Jun, 57(6), 468 - 73
Cerebral, myocardial and cutaneous ischemic necrosis associated with calcific emboli from aortic and mitral valve calcification in a patient with end-stage renal disease; Li Y et al.; We report the case of a 57-year-old diabetic male with chronic renal failure who developed secondary hyperparathyroidism and calcification of mitral and aortic valves and interatrial septum . Multiple ischemic lesions developed in the skin of hands, feet and penis, and in the brain, and these were presumed to be due to septic emboli from cardiac valvular infective endocarditis . Multiple blood cultures were negative, however, and despite antibiotic therapy the patient expired . Autopsy (limited to trunk) demonstrated multiple calcific emboli in the heart and spleen, apparently derived from the prominent calcific deformities in the aortic and mitral valves . These were associated with acute and organizing myocardial infarcts and acute splenic infarcts, suggesting that the multiple ischemic lesions in the brain were also due to calcific emboli . A possible contributory component of infective endocarditis, however, was indicated by postmortem cultures of aortic and mitral valves positive for Enterococcus faecium . Calcific embolism is a rarely recognized but potentially lethal complication of end-stage renal disease, and the clinical diagnosis and the preventive therapeutic options for the control of the product of calcium and phosphate and/or parathyroidectomy should be considered.

J Biol Chem, 2002 Sep 27, 277(39), 35801 - 7 Epub 2002 Jun 19.
Balance between two transpeptidation mechanisms determines the expression of beta-lactam resistance in Enterococcus faecium; Mainardi JL et al.; The d,d-transpeptidase activity of high molecular weight penicillin-binding proteins (PBPs) is essential to maintain cell wall integrity as it catalyzes the final cross-linking step of bacterial peptidoglycan synthesis . We investigated a novel beta-lactam resistance mechanism involving by-pass of the essential PBPs by l,d-transpeptidation in Enterococcus faecium . Determination of the peptidoglycan structure by reverse phase high performance liquid chromatography coupled to mass spectrometry revealed that stepwise selection for ampicillin resistance led to the gradual replacement of the usual cross-links generated by the PBPs (d-Ala(4) --> d-Asx-Lys(3)) by cross-links resulting from l,d-transpeptidation (l-Lys(3) --> d-Asx-Lys(3)) . This was associated with no modification of the level of production of the PBPs or of their affinity for beta-lactams, indicating that altered PBP activity was not required for ampicillin resistance . A beta-lactam-insensitive l,d-transpeptidase was detected in membrane preparations of the parental susceptible strain . Acquisition of resistance was not because of variation of this activity . Instead, selection led to production of a beta-lactam-insensitive d,d-carboxypeptidase that cleaved the C-terminal d-Ala residue of pentapeptide stems in vitro and caused massive accumulation of cytoplasmic precursors containing a tetrapeptide stem in vivo . The parallel dramatic increase in the proportion of l-Lys(3) --> d-Asx-Lys(3) cross-links showed that the enzyme was activating the resistance pathway by generating the substrate for the l,d-transpeptidase.

Chem Biol Interact, 2002 May 20, 140(2), 185 - 98
The antimicrobial properties of milkfat after partial hydrolysis by calf pregastric lipase; Sun CQ et al.; Studies on the kinetic characteristics of calf pregastric lipase (EC 3.1.1.3) have shown that it preferentially releases short chain fatty acids (SCFAs) from bovine milkfat . The released fatty acids form mixed micelle structures . The aim of this investigation has been to test whether hydrolysed milkfat is antimicrobial, and how the state of the emulsion alters the bactericidal or bacteriostatic effects . Partial hydrolysis of milkfat by pregastric lipase was carried out in two types of emulsion systems, containing either Triton X-100 or casein/lecithin, plus milkfat in citrate/phosphate buffer (pH 5.0-6.0) . The concentrations and compositions of fatty acids were determined by gas chromatography . The minimum percentages of hydrolysed milkfat which affected growth and survival of selected Gram-positive and Gram-negative bacteria were measured . The bacterial experiments were repeated using pure fatty acids at similar concentrations . Lauric acid (C12:0) was found to be the most potent bactericidal fatty acid against Enterococcae (Gram-positive), and caprylic acid (C8:0) was the most potent against coliforms (Gram-negative) . Use of Triton X-100 for milkfat emulsification provided a more compatible medium for studying bacterial growth in the hydrolysed milkfat than did use of casein/lecithin . The results also show that the antimicrobial effects of individual fatty acids released from hydrolysed milkfat were at least additive and suggest that hydrolysis of milkfat may be a significant factor in controlling growth of organisms imbibed with food in pre-weaned animals . The amount of pregastric catalyzed triglyceride hydrolysis in the digestive tract is sufficient to produce an antibacterial concentration of fatty acids and monoglycerides.

Int J Food Microbiol, 2002 Jul 25, 77(1-2), 109 - 15
Gastrointestinal transit survival of an Enterococcus faecium probiotic strain administered with or without vancomycin; Lund B et al.; The primary aim of this study was to evaluate if an ingested probiotic, containing viable Enterococcus faecium could survive gastrointestinal transit and if so, correlate the amount of the recovered probiotic strain with the host's own enterococci . The second aim was to investigate if simultaneous vancomycin intake influenced the survival and persistence of the probiotic strain and the stability of endogenous enterococci strains . Twenty healthy volunteers were given the probiotic product once daily for 10 days . Half of the subjects were simultaneously given vancomycin . Isolates of E . faecium strains were genotypically or phenotypically analysed with pulsed-field gel electrophoresis (PFGE) and the PhenePlate system, respectively . In eight of the ten volunteers given only the probiotic, the ingested E . faecium could be detected on day 10, while in none on day 31 . From subjects given both probiotic and vancomycin no ingested E . faecium could be detected on day 10 or day 31 . The estimated amount of ingested E . faecium recovered from faeces on day 10 ranged from 1.2 x 10(3) to 4.2 x 10(6) colony forming units per gram faeces, which in several cases were a substantial part of the total amount of E . faecium . The E . faecium isolated before probiotic plus vancomycin administration showed no close relationship to the ones isolated 3 weeks after ceased intake in any subjects . In conclusion, the ingested E . faecium strain can survive gastrointestinal transit . After intake, the E . faecium probiotic strain might become a large part of the total E . faecium population . The occurrence of the probiotic strain in the human gut seems to be transient after intake stop . Re-colonization of E . faecium after simultaneous probiotic plus vancomycin intake occurs mainly with strains without close genetic relationship to the strains harboured before treatment or to the ingested E . faecium strain.

FEMS Microbiol Rev, 2002 Jun, 26(2), 163 - 71
Enterococci from foods; Giraffa G; Enterococci have recently emerged as nosocomial pathogens . Their ubiquitous nature determines their frequent finding in foods as contaminants . In addition, the notable resistance of enterococci to adverse environmental conditions explains their ability to colonise different ecological niches and their spreading within the food chain through contaminated animals and foods . Enterococci can also contaminate finished products, such as fermented foods and, for this reason, their presence in many foods (such as cheeses and fermented sausages) can only be limited but not completely eliminated using traditional processing technologies . Enterococci are low grade pathogens but their intrinsic resistance to many antibiotics and their acquisition of resistance to the few antibiotics available for treatment in clinical therapy, such as the glycopeptides, have led to difficulties and a search for new drugs and therapeutic options . Enterococci can cause food intoxication through production of biogenic amines and can be a reservoir for worrisome opportunistic infections and for virulence traits . Clearly, there is no consensus on the acceptance of their presence in foodstuffs and their role as primary pathogens is still a question mark . In this review, the following topics will be covered: (i) emergence of the enterococci as human pathogens due to the presence of virulence factors such as the production of adhesins and aggregation substances, or the production of biogenic amines in fermented foods; (ii) their presence in foods; (iii) their involvement in food-borne illnesses; (iv) the presence, selection and spreading of antibiotic-resistant enterococci as opportunistic pathogens in foods, with particular emphasis on vancomycin-resistant enterococci.

Clin Infect Dis, 2002 Jul 1, 35(1), 18 - 25 Epub 2002 Jun 07.
To gown or not to gown: the effect on acquisition of vancomycin-resistant enterococci; Puzniak LA et al.; Infection-control recommendations include the use of gowns and gloves to prevent horizontal transmission of vancomycin-resistant enterococci (VRE) . This study sought to determine whether the use of a gown and gloves gives greater protection than glove use alone against VRE transmission in a medical intensive care unit (MICU) . From 1 July 1997 through 30 June 1998 and from 1 July 1999 through 31 December 1999, health care personnel and visitors were required to don gloves and gowns upon entry into rooms where there were patients infected with nosocomial pathogens . From 1 July 1998 through 30 June 1999, only gloves were required under these same circumstances . During the gown period, 59 patients acquired VRE (9.1 cases per 1000 MICU-days), and 73 patients acquired VRE during the no-gown period (19.6 cases per 1000 MICU-days; P<.01) . The adjusted risk estimate indicated that gowns were protective in reducing VRE acquisition in an MICU with high VRE colonization pressure.

Eur J Biochem, 2002 Jun, 269(11), 2740 - 6
Purification and characterization of VanXY(C), a D,D-dipeptidase/D,D-carboxypeptidase in vancomycin-resistant Enterococcus gallinarum BM4174; Podmore AH et al.; VanXY(C), a bifunctional enzyme from VanC-phenotype Enterococcus gallinarum BM4174 that catalyses D,D-peptidase and D,D-carboxypeptidase activities, was purified as the native protein, as a maltose-binding protein fusion and with an N-terminal tag containing six histidine residues . The kinetic parameters of His(6)-VanXY(C) were measured for a variety of precursors of peptidoglycan synthesis involved in resistance: for D-Ala-D-Ala, the K(m) was 3.6 mm and k(cat), 2.5 s(-1); for UDP-MurNAc-L-Ala-D-Glu-L-Lys-DAla-D-Ala (UDP-MurNAc-pentapeptide{Ala}), K(m) was 18.8 mm and k(cat) 6.2 s(-1); for D-Ala-D-Ser, K(m) was 15.5 mm and k(cat) 0.35 s(-1) . His(6)-VanXYC was inactive against the peptidoglycan precursor UDP-MurNAc-L-Ala-D-Glu-L-Lys-D-Ala-D-Ser (UDP-MurNAc-pentapeptide{Ser}) . The rate of hydrolysis of the terminal D-Ala of UDP-MurNAc-pentapeptide{Ala} was inhibited 30% by 2 mm D-Ala-D-Ser or UDP-MurNAc-pentapeptide{Ser} . Therefore preferential hydrolysis of substrates terminating in D-Ala would occur during peptidoglycan synthesis in E . gallinarum BM4174, leaving precursors ending in D-Ser with a lower affinity for glycopeptides to be incorporated into peptidoglycan.Mutation of an aspartate residue (Asp59) of His-tagged VanXY(C) corresponding to Asp68 in VanX to Ser or Ala, resulted in a 50% increase and 73% decrease, respectively, of the specificity constant (k(cat)/K(m)) for D-Ala-D-Ala . This situation is in contrast to VanX in which mutation of Asp68-->Ala produced a greater than 200,000-fold decrease in the substrate specificity constant . This suggests that Asp59, unlike Asp68 in VanX, does not have a pivotal role in catalysis.

Appl Environ Microbiol, 2002 Jun, 68(6), 3133 - 7
Vancomycin-resistant Enterococcus faecium (VREF) from Norwegian poultry cluster with VREF from poultry from the United Kingdom and The Netherlands in an amplified fragment length polymorphism genogroup; Borgen K et al.; The genetic relationship between 197 vancomycin-resistant Enterococcus faecium (VREF) isolates and 21 vancomycin-susceptible E . faecium isolates from Norwegian poultry was analyzed by amplified fragment length polymorphism (AFLP) . The isolates were compared to 255 VREF isolates from various sources and countries . The Norwegian isolates constituted a relatively homogeneous population of E . faecium and clustered in a previously defined poultry AFLP genogroup.

J Clin Microbiol, 2002 Jun, 40(6), 2308 - 10
Enterococcus gallinarum endocarditis occurring on native heart valves; Dargere S et al.; We report the first case of Enterococcus gallinarum endocarditis developing on normal native heart valves . Using phenotypic and molecular methods, a precise identification of this naturally vancomycin-resistant species allowed an optimal antibiotic therapy and the patient's recovery.

J Clin Microbiol, 2002 Jun, 40(6), 2084 - 8
Frequent transmission of enterococcal strains between mechanically ventilated patients treated at an intensive care unit; Lund B et al.; The objectives of this investigation were to study the respiratory tract colonization and transmission of enterococci between 20 patients treated with mechanical ventilation at an intensive care unit (ICU), to compare genotyping with phenotyping, and to determine the antibiotic susceptibilities of the isolated enterococci . Samples were collected from the oropharynx, stomach, subglottic space, and trachea within 24 h of intubation, every third day until day 18, and thereafter every fifth day until day 33 . Enterococcal isolates (n = 170) were analyzed by pulsed-field gel electrophoresis and with the PhenePlate (PhP) system . The antimicrobial susceptibilities to five agents were determined . Seventeen of the 20 subjects were colonized with enterococci in the respiratory tract; 12 were colonized in the lower respiratory tract . Genotype analyses suggested that 13 patients were involved in a transmission event, including all patients intubated more than 12 days . In conclusion, colonization of resistant enterococci in the respiratory tract of intubated patients treated at an ICU was common . Transmission of enterococci between patients occurred frequently . Prolonged intubation period seems to be a risk factor for enterococcal cross-transmission.

J Clin Microbiol, 2002 Jun, 40(6), 1977 - 84
Automated ribotyping of vancomycin-resistant Enterococcus faecium isolates; Brisse S et al.; Vancomycin-resistant Enterococcus faecium (VREF) strains represent an important threat in hospital infections in the United States and are found at high frequencies in both the community and farm animals in Europe . We evaluated automated ribotyping for interlaboratory reproducibility by using the restriction enzymes EcoRI and BamHI and compared ribotyping to both amplification of fragment length polymorphism (AFLP) analysis and multilocus sequence typing (MLST) to assess its discriminatory power and capacity for the identification of epidemiologically important strains . Of 19 (EcoRI) and 16 (BamHI) isolates tested in duplicate in two laboratories, 18 (95%) and 16 (100%), respectively, showed reproducible ribotypes . These high reproducibility rates were obtained only after manual refinement of the automated fingerprint analysis . A group of 49 VREF strains initially selected to represent 32 distinct AFLP types were separated into 28 EcoRI ribotypes, 25 BamHI ribotypes, and 28 sequence types . Ribotyping with EcoRI and BamHI was able to discern the host-specific genogroups recently disclosed by AFLP typing and MLST and to distinguish most strains containing the esp gene, a marker specific for strains causing hospital outbreaks . An expandable ribotype identification library was created . We recommend EcoRI as the enzyme of choice for automated ribotyping of VREF strains . Given the high level of discrimination of VREF strains, the high rate of interlaboratory reproducibility, and the potential for the identification of epidemiologically important genotypes, automated ribotyping appears to be a very valuable approach for characterizing VREF strains.

J Clin Microbiol, 2002 Jun, 40(6), 1963 - 71
Multilocus sequence typing scheme for Enterococcus faecium; Homan WL et al.; A multilocus sequence typing (MLST) scheme has been developed for Enterococcus faecium . Internal fragments from seven housekeeping genes of 123 epidemiologically unlinked isolates from humans and livestock and 16 human-derived isolates from several outbreaks in the United States, the United Kingdom, Australia, and The Netherlands were analyzed . A total of 62 sequence types were detected in vancomycin-sensitive E . faecium (VSEF) and vancomycin-resistant E . faecium (VREF) isolates . VSEF isolates were genetically more diverse than VREF isolates . Both VSEF and VREF isolates clustered in host-specific lineages that were similar to the host-specific clustering obtained by amplified fragment length polymorphism analysis . Outbreak isolates from hospitalized humans clustered in a subgroup that was defined by the presence of a unique allele from the housekeeping gene purK and the surface protein gene esp . The MLST results suggest that epidemic lineages of E . faecium emerged recently worldwide, while genetic variation in both VREF and VSEF was created by longer-term recombination . The results show that MLST of E . faecium provides an excellent tool for isolate characterization and long-term epidemiologic analysis.

J Cataract Refract Surg, 2002 Jun, 28(6), 977 - 81
Prophylactic intracameral cefuroxime . Efficacy in preventing endophthalmitis after cataract surgery; Montan PG et al.; PURPOSE: To evaluate the efficacy of prophylactic intracameral cefuroxime in preventing endophthalmitis in cataract surgery . SETTING: Department of Ophthalmology, St . Eriks Hospital, Stockholm, Sweden . METHODS: In a noncontrolled retrospective observational study, all cases of recorded postoperative endophthalmitis were related to the total number of uncombined cataract procedures from January 1996 to December 2000 . RESULTS: Twenty cases of postoperative endophthalmitis occurred in 32180 procedures, yielding an overall rate of 0.06% . Cefuroxime-resistant organisms accounted for 12 of 13 culture-positive cases, and enterococci were the most common etiology . CONCLUSIONS: Intracameral cefuroxime 1 mg appeared to effectively inhibit sensitive bacterial strains and was associated with a low frequency of postoperative endophthalmitis . The causative organisms of future incidents of postoperative endophthalmitis will determine whether the present protocol must be reappraised.

Ugeskr Laeger, 2002 Apr 29, 164(18), 2386 - 90
{Enterococcal infections . Clinical findings and treatment considering antibiotic resistance in Denmark}; Olesen HV et al.; Enterococcus has become a more frequent cause of serious infections over the last 10-15 years . The infections are primarily nosocomial, owing to compromised immunity in the patients and excessive use of antibiotics in the hospitals . The rise is marked in the USA, where the enterococci furthermore tend to become multiresistant . Abroad, many enterococci have developed resistance to all available antibiotics, and their spread is now controllable only by strict hygienic precautions . No increase in enterococcal infections has been noted in Denmark, and very few clinical isolates of vancomycin-resistant enterococci have been found . Because of the worldwide relevance, we present a review of enterococcal infections with the focus on endocarditis and bacteraemia . However, we would emphasise that the classic combination of a penicillin and an aminoglycoside still provides adequate treatment of enterococcal infections in Denmark.

New Microbiol, 2002 Apr, 25(2), 205 - 12
The occurrence of vancomycin-resistant enterococci in hematological patients in relation to antibiotic use; Kolar M et al.; Very important bacterial pathogens found in hematological patients at present are vancomycin-resistant enterococci (VRE) . The main goal of this retrospective study was to assess their occurrence in relation to antibiotic use . We isolated 1918 Enterococcus strains, in toto, 138 (7.2%) of which proved to be VRE . The VRE most frequently identified were Enterococcus faecium VanA (77%) and Enterococcusfaecalis VanB (12%), mostly isolated from stools (57%) . Comparing the development of the selection pressure of antibiotics and percentage of VRE in each period of observation, an effect of the administration of each antibiotic group on the occurrence of VRE can be presumed . A reduction in the administration of third generation cephalosporins, glycopeptides and fluoroquinolones and its replacement by penicillin antibiotics combined with inhibitors of bacterial beta-lactamases, contributed to the cessation of VRE incidence and succeeding reduced occurrence from 15.1% in the second half of 1998 to 6.1% in the first half of 2000.

Clin Infect Dis, 2002 Jun 1, 34(11), E61 - 3 Epub 2002 May 09.
Prosthetic valve endocarditis due to vancomycin-resistant Enterococcus faecium: treatment with chloramphenicol plus minocycline; Safdar A et al.; We report a case of prosthetic valve endocarditis and persistent bacteremia due to vancomycin-resistant Enterococcus faecium . The combination of parenteral chloramphenicol plus minocycline therapy was administered for 8 weeks and resulted in cure after treatment with quinupristin-dalfopristin had failed.

J Hosp Infect, 2002 May, 51(1), 52 - 8
Effectiveness of a multifaceted infection control policy in reducing vancomycin usage and vancomycin-resistant enterococci at a tertiary care cancer centre; Shaikh ZH et al.; We undertook a prospective cohort study to evaluate the role of a multifaceted infection control policy including the use of a "vancomycin order form," in decreasing the transmission of vancomycin-resistant enterococci (VRE) . In January 1997, a multifaceted infection-control policy was implemented amongst patients admitted to the M . D . Anderson Cancer Center in whom neutropenic fever developed or who were found to be colonized or infected with VRE . As part of this programme, we initiated the use of a vancomycin order form to reduce the use of empirical vancomycin . The total incidence of VRE infections declined from 0.437/1000 patient days in 1996-97 to 0.229/1000 patient days in 1998-99 (P=0.008) . The VRE bloodstream infections declined from 0.338/1000 patient days in 1996-97 to 0.181/1000 patient days in 1998-99 (P=0.027) . Empiric vancomycin use decreased from 416 g/1000 patient days in 1996-97 to 208 g/1000 patient days in 1998-99 (P<0.001), resulting in a decreased vancomycin cost from $2561 US dollars/1000 patient days in 1996-97 to $1195 US dollars/1000 patient days in 1997-98 (P<0.001) . We conclude that a multifaceted infection control policy incorporating the use of a vancomycin order form can effectively decrease the use of empirical vancomycin and can play a role in limiting the spread of VRE in an endemic setting .

Diagn Microbiol Infect Dis, 2002 Apr, 42(4), 273 - 7
A PCR assay for rapid detection of vancomycin-resistant enterococci; Perez-Hernandez X et al.; Since the first report of a vancomycin-resistant enterococcal clinical isolate, these Gram-positive bacteria have emerged as important nosocomial pathogens . Several glycopeptide resistance phenotypes can be distinguished on the basis of the level and inducibility of resistance to vancomycin and teicoplanin . In the present study, we developed a multiplex PCR, which allows the simultaneous identification of enterococci at the genus level and detection of the most frequent glycopeptide resistance genotypes . Five primer sets targeting the genes vanA, vanB, vanC1, vanC2/C3 and tuf were used in one reaction tube with bacterial DNA extracted from three to five colonies . This PCR method is suitable for the rapid detection of vancomycin-resistant enterococci.

Infect Control Hosp Epidemiol, 2002 Apr, 23(4), 207 - 11
Duration of colonization with vancomycin-resistant Enterococcus; Byers KE et al.; OBJECTIVE: To determine the duration of colonization with vancomycin-resistant Enterococcus (VRE) and the adequacy of 3 consecutive negative cultures to determine clearance . DESIGN: Retrospective cohort study . SETTING: A university hospital . POPULATION: Patients identified by perirectal cultures as VRE carriers who had follow-up cultures . METHODS: Follow-up perirectal cultures were collected in inpatient and outpatient settings, at least 1 week apart, when patients were not receiving antibiotics with activity against VRE . The likelihood of culture positivity was analyzed given prior culture results and time from the initial positive culture . RESULTS: A total of 116 patients colonized with VRE had 423 follow-up cultures, a mean of 204 days (range, 4 to 709 days) after their initial isolate . The first follow-up culture, collected a mean of 125 days after the initial positive isolate, was negative in 64% . After 1 negative follow-up culture, the next one was negative in 92% of the patients . After 2 negative cultures, 95% remained culture-negative . After 3 sequential negative cultures, 35 (95%) of 37 patients remained culture-negative . As the interval between the initial and the follow-up isolates increased, the probability that a subsequent culture would be positive decreased (P < .001, chi square for trend) . Prolonged hospitalization, intensive care, and antibiotic use each decreased the likelihood of clearing VRE . CONCLUSION: These data support the Centers for Disease Control and Prevention criterion of 3 sequential negative cultures, at least 1 week apart, to remove patients from VRE isolation . Nevertheless, this may reflect a decrease in the quantity of VRE to an undetectable level and these patients should be observed for relapse, especially when re-treated with antibiotics.

J Microbiol Methods, 2002 Jul, 50(2), 115 - 21
Identification of Enterococcus spp . based on specific hybridisation with 16S rDNA probes; Manero A et al.; The conventional methods for routine enterococci species identification are usually based on phenotypic characteristics . However, in recent years, some studies have defined specific probes based on both 16S and 23S rRNA genes for the identification of some Enterococcus spp . A set of probes based on the 16S rRNA gene has been developed in order to evaluate the usefulness of a six-step biochemical key for species level identification of enterococci . Probe specificity has been evaluated with type collection and environmental strains by dot blot hybridisation . A high correlation was obtained between biochemical key and hybridisation identifications . This set of probes provides a confirmative method for phenotypic species identification.

J Biol Chem, 2002 Jul 5, 277(27), 24405 - 10 Epub 2002 Apr 30.
Arginine residue at position 573 in Enterococcus hirae vacuolar-type ATPase NtpI subunit plays a crucial role in Na+ translocation; Kawano M et al.; The 76-kDa NtpI subunit constitutes the membrane-embedded V(0) moiety of Enterococcus hirae vacuolar type Na+-ATPase with a 16-kDa NtpK hexamer containing Na+ binding sites . In this study, we investigated the role of an arginine residue, which is highly conserved among the corresponding subunits of bacterial vacuolar-type ATPases, at position 573 of NtpI . Substitution of Glu, Leu, or Gln for Arg-573 abolished sodium transport and sodium-stimulated ATP hydrolysis of the enzyme . The conservative replacement of Arg by Lys lowered both activities about one-fifth of those of the wild type enzyme . We have reported previously on ATP-dependent negative cooperativity for Na+ coupling of this enzyme (Murata, T., Kakinuma, Y., and Yamato, I . (2001) J . Biol . Chem . 276, 48337-48340) . The negative cooperativity for the Na+ dependence of ATPase activity was weakened by the mutation R573K; the Hill coefficients for the wild type and mutant enzymes at a saturated ATP concentration were 0.22 +/- 0.03 and 0.40 +/- 0.05, respectively . The Hill coefficients of both enzymes at limited ATP concentrations approached 1 . These results indicate that NtpI Arg-573 is indispensable for sodium translocation and for the cooperative features of E . hirae vacuolar-type ATPase.

Plasmid, 2002 Mar, 47(2), 138 - 47
Parameters associated with cloning in Actinobacillus actinomycetemcomitans; Galli DM et al.; Characterization of virulence traits in Actinobacillus actinomycetemcomitans requires the application of recombinant DNA techniques . To develop appropriate genetic tools it is necessary to identify suitable host-vector systems . The current study assessed cloning parameters in A . actinomycetemcomitans for two previously described vectors, pDMG4 and pMMB67 . It was determined that the maximum size of recombinant molecules that could be transferred to A . actinomycetemcomitans strain ATCC29522 via electroporation was 33 kb . The size limit for transformation of the same strain with ligation mixtures (direct cloning), however, was limited to 23-24 kb . Additional experiments included electroporation of various A . actinomycetemcomitans strains with plasmid DNA isolated from Escherichia coli and different A . actinomycetemcomitans sources . Differences in transformation efficiencies suggested the presence of a restriction modification system for pDMG4 in some strains of A . actinomycetemcomitans . Cloning of portions of the enterococcal plasmid pJH1 into A . actinomycetemcomitans resulted in the insertion of the intact vector into the chromosome .

Clin Infect Dis, 2002 May 15, 34(10), 1412 - 4 Epub 2002 Apr 23.
Linezolid treatment for osteomyelitis due to vancomycin-resistant Enterococcus faecium; Till M et al.; The incidence of nosocomial infections caused by vancomycin-resistant enterococci has risen substantially during the past 15 years . We report the use of linezolid for the successful treatment of hip prosthesis infection associated with osteomyelitis due to vancomycin-resistant Enterococcus faecium.

J Clin Microbiol, 2002 May, 40(5), 1858 - 61
Comparison of an automated ribotyping system to restriction endonuclease analysis and pulsed-field gel electrophoresis for differentiating vancomycin-resistant Enterococcus faecium isolates; Price CS et al.; The RiboPrinter Microbial Characterization System was compared with pulsed-field gel electrophoresis (PFGE), restriction endonuclease analysis (REA), and epidemiological data for typing 45 vancomycin-resistant Enterococcus faecium (VRE) isolates . In 21 clinically related isolates, 90 to 100% were similar by PFGE and REA, but only 57% were similar by the RiboPrinter . In another eight clinically related isolates, three isolates similar by PFGE and REA were all unique by the RiboPrinter . In contrast, in 16 clinically unrelated isolates, the predominant RiboPrinter ribotype represented 50% of the strains, while the largest PFGE and REA clones represented less than 19% of the strains . These data suggest that the RiboPrinter is not reliable for VRE investigation.

Biochemistry, 2002 May 7, 41(18), 5822 - 9
Copper transfer from the Cu(I) chaperone, CopZ, to the repressor, Zn(II)CopY: metal coordination environments and protein interactions; Cobine PA et al.; Extracellular copper regulates the DNA binding activity of the CopY repressor of Enterococcus hirae and thereby controls expression of the copper homeostatic genes encoded by the cop operon . CopY has a CxCxxxxCxC metal binding motif . CopZ, a copper chaperone belonging to a family of metallochaperones characterized by a MxCxxC metal binding motif, transfers copper to CopY . The copper binding stoichiometries of CopZ and CopY were determined by in vitro metal reconstitutions . The stoichiometries were found to be one copper(I) per CopZ and two copper(I) per CopY monomer . X-ray absorption studies suggested a mixture of two- and three-coordinate copper in Cu(I)CopZ, but a purely three-coordinate copper coordination with a Cu-Cu interaction for Cu(I)2CopY . The latter coordination is consistent with the formation of a compact binuclear Cu(I)-thiolate core in the CxCxxxxCxC binding motif of CopY . Displacement of zinc, by copper, from CopY was monitored with 2,4-pyridylazoresorcinol . Two copper(I) ions were required to release the single zinc(II) ion bound per CopY monomer . The specificity of copper transfer between CopZ and CopY was dependent on electrostatic interactions . Relative copper binding affinities of the proteins were investigated using the chelator, diethyldithiocarbamic acid (DDC) . These data suggest that CopY has a higher affinity for copper than CopZ . However, this affinity difference is not the sole factor in the copper exchange; a charge-based interaction between the two proteins is required for the transfer reaction to proceed . Gain-of-function mutation of a CopZ homologue demonstrated the necessity of four lysine residues on the chaperone for the interaction with CopY . Taken together, these results suggest a mechanism for copper exchange between CopZ and CopY.

J Appl Microbiol, 2002, 92(5), 951 - 7
Characterization of yellow-pigmented and motile enterococci isolated from intestines of the garden snail Helix aspersa; Svec P et al.; AIMS: Enterococci associated with garden snails (Helix aspersa) were studied in order to obtain reliable species identification and characterization . METHODS AND RESULTS: Twelve yellow-pigmented and motile enterococci, isolated from the intestines of garden snails, were phenotypically close to Enterococcus casseliflavus, but they showed certain unusual biochemical characteristics . tRNA intergenic length polymorphism analysis (tDNA-PCR) divided all strains studied into two groups, in full agreement with biochemical test results . 16S rDNA sequencing, DNA base composition analysis and DNA-DNA hybridization results showed unambiguously that the enterococci studied belonged to the species Ent . casseliflavus . The representative strains of described ecovars were deposited in the Czech Collection of Microorganisms (CCM) as Ent . casseliflavus CCM 4868, 4869, 4870 and 4871 . CONCLUSIONS: Enterococcus casseliflavus associated with garden snails can be subdivided into groups . SIGNIFICANCE AND IMPACT OF THE STUDY: Enterococcus casseliflavus differs from other enterococcal species in that it is typically associated with plants, soil, water and invertebrate animals . The different groups that can be found in these widely occurring bacteria are possibly source-specific ecovars, as exemplified by the Ent . casseliflavus inhabiting the intestines of snails.

J Appl Microbiol, 2002, 92(5), 821 - 7
Differentiation and identification of Enterococcus durans, E . hirae and E . villorum; Devriese LA et al.; AIMS: To compare different tests in the identification of Enterococcus durans, E . hirae and E . villorum strains . These bacteria belong to the E . faecium species group and are phylogenetically closely related, as evidenced by 16S rRNA sequence homologies of over 98.8% . METHODS AND RESULTS: Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis of whole-cell protein, tRNA interpacer polymerase chain reaction (PCR) and arbitrarily-primed (D11344-primed AP) -PCR analysis correctly identified all three species in a collection of strains from very diverse origins . In contrast, biochemical reactions only allowed the unequivocal differentiation of the three species as a group from the other enterococci . Within this group, D-xylose acidification can be used to differentiate E . villorum, but exceptions occur . Strains highly susceptible to clindamycin can be identified as E . durans, but many strains of this species cannot be differentiated from E . hirae and E . villorum due to acquired resistance . CONCLUSIONS: Despite their close relationship, E . durans, E . hirae and E . villorum can be differentiated by genomic methods and by whole-cell protein analysis . SIGNIFICANCE AND IMPACT OF THE STUDY: Only a minority of strains of these three enterococcal species can be identified reliably by the currently available and commonly applied phenotypic tests.

Proc Natl Acad Sci U S A, 2002 Apr 30, 99(9), 6434 - 9 Epub 2002 Apr 23.
Animal antibiotic use has an early but important impact on the emergence of antibiotic resistance in human commensal bacteria; Smith DL et al.; Antibiotic use is known to promote the development of antibiotic resistance, but substantial controversy exists about the impact of agricultural antibiotic use (AAU) on the subsequent emergence of antibiotic-resistant bacteria among humans . AAU for animal growth promotion or for treatment or control of animal diseases generates reservoirs of antibiotic-resistant (AR) bacteria that contaminate animal food products . Mathematical models are an important tool for understanding the potential medical consequences of this increased exposure . We have developed a mathematical model to evaluate factors affecting the prevalence of human commensal AR bacteria that cause opportunistic infections (e.g., enterococci) . Our analysis suggests that AAU hastens the appearance of AR bacteria in humans . Our model indicates that the greatest impact occurs very early in the emergence of resistance, when AR bacteria are rare, possibly below the detection limits of current surveillance methods.

Curr Opin Infect Dis, 2001 Aug, 14(4), 449 - 53
Infection control in pediatric hospitals; Neely M et al.; Important characteristics of hospital infection control are specific to pediatric facilities . For example, colonization and infection with vancomycin-resistant enterococci, which are widely spread in many units housing adult patients, are uncommon in children, especially in the neonatal intensive care unit where vancomycin use is heavy . Characteristics of the neonatal intensive care unit, such as the insulated environment and infrequent treatment with antibiotics with broad anaerobic activity, likely account for this finding . Artificial fingernails have been discovered to promote colonization with potential pathogens; their implication in recent nursery epidemics emphasizes the need to prohibit their use in this environment in particular . Finally, nosocomial viral infections occur with regularity in pediatric hospitals . Programs that successfully and cost-effectively control hospital spread of respiratory syncytial virus, however, demonstrate that rational, multifaceted interventions can nearly eliminate transmission of certain viral pathogens on the pediatric wards.

Rev Med Chil, 2002 Jan, 130(1), 45 - 9
{Classic and molecular methodologies for the identification of Enterococcus species}; Sepulveda M et al.; BACKGROUND: Enterococcus is a bacterial genus with low virulence . However, in the last years, the importance of some enterococcus species as nosocomial pathogens has increased, specially due to their resistance to some antimicrobial . AIM: To identify enterococcus strains using classical biochemical techniques and genomic amplification with Polymerase Chain Reaction (PCR) . MATERIAL AND METHODS: Three hundred and five enterococcus strains, isolated between 1996 and 1999, from different clinical specimens in hospitals and other centers of the VIIIth Region of Chile, were studied . The isolates were identified, to the species level, according to the scheme proposed by Carvalho et al . Identification of some strains was confirmed by PCR . RESULTS: Eighty nine percent of isolates were identified as E foecalis, 10.2% as E foecium and 3.3% as other species . CONCLUSIONS: PCR is a fast and promising technique, useful in the identification of Enterococcus species.

Antimicrob Agents Chemother, 2002 May, 46(5), 1410 - 6
tcrB, a gene conferring transferable copper resistance in Enterococcus faecium: occurrence, transferability, and linkage to macrolide and glycopeptide resistance; Hasman H et al.; A newly discovered gene, designated tcrB, which is located on a conjugative plasmid conferring acquired copper resistance in Enterococcus faecium, was identified in an isolate from a pig . The tcrB gene encodes a putative protein belonging to the CPx-type ATPase family with homology (46%) to the CopB protein from Enterococcus hirae . The tcrB gene was found in E . faecium isolated from pigs (75%), broilers (34%), calves (16%), and humans (10%) but not in isolates from sheep . Resistant isolates, containing the tcrB gene, grew on brain heart infusion agar plates containing up to 28 mM CuSO4 compared to only 4 mM for the susceptible isolates . Copper resistance, and therefore the presence of the tcrB gene, was strongly correlated to macrolide and glycopeptide resistance in isolates from pigs, and the tcrB gene was shown to be located on the same conjugative plasmid as the genes responsible for resistance to these two antimicrobial agents . The frequent occurrence of this new copper resistance gene in isolates from pigs, where copper sulfate is being used in large amounts as feed additive, suggests that the use of copper has selected for resistance.

J Clin Microbiol, 2002 Apr, 40(4), 1160 - 3
Molecular characterization of vancomycin-resistant Enterococci repopulating the gastrointestinal tract following treatment with a novel glycolipodepsipeptide, ramoplanin; Baden LR et al.; We characterized baseline and repopulating stool isolates recovered during a phase II trial of ramoplanin for the treatment of patients with stool carriage of vancomycin-resistant enterococci (VRE) . Repopulation with a strain with a related genotype was found in 74, 60, and 53% of individuals in groups treated with placebo, 100 mg of ramoplanin, and 400 mg of ramoplanin, respectively . All ramoplanin-treated patients with a culture positive for VRE at day 7 had a relapse caused by a genotypically related isolate . In ramoplanin-treated patients, antibiotics with activities against anaerobic organisms were associated with positive cultures on day 7 (relative risk {RR} = 8.8; P = 0.004), and the avoidance of such antibiotics was significantly associated with culture negativity through day 21 (RR = 0.16; P = 0.02).

J Clin Microbiol, 2002 Apr, 40(4), 1140 - 5
Enterococcus gilvus sp . nov . and Enterococcus pallens sp . nov . isolated from human clinical specimens; Tyrrell GJ et al.; Light yellow-pigmented (strain PQ1) and yellow-pigmented (strain PQ2), gram-positive, non-spore-forming, nonmotile bacteria consisting of pairs or chains of cocci were isolated from the bile of a patient with cholecystitis (PQ1) and the peritoneal dialysate of another patient with peritonitis (PQ2) . Morphologically and biochemically, the organisms phenotypically belonged to the genus Eterococcus . Whole-cell protein (WCP) analysis and sequence analysis of a segment of the 16S rRNA gene suggested that they are new species within the genus Enterococcus . PQ1 and PQ2 displayed less than 70% identities to other enterococcal species by WCP analysis . Sequence analysis showed that PQ1 shared the highest level of sequence similarity with Enterococcus raffinosus and E . malodoratus (sequence similarities of 99.8% to these two species) . Sequence analysis of PQ2 showed that it had the highest degrees of sequence identity with the group I enterococci E . malodoratus (98.7%), E . raffinosus (98.6%), E . avium (98.6%), and E . pseudoavium (98.6%) . PQ1 and PQ2 can be differentiated from the other Enterococcus spp . in groups II, III, IV, and V by their phenotypic characteristics: PQ1 and PQ2 produce acid from mannitol and sorbose and do not hydrolyze arginine, placing them in group I . The yellow pigmentation differentiates these strains from the other group I enterococci . PQ1 and PQ2 can be differentiated from each other since PQ1 does not produce acid from arabinose, whereas PQ2 does . Also, PQ1 is Enterococcus Accuprobe assay positive and pyrrolidonyl-beta-naphthylamide hydrolysis positive, whereas PQ2 is negative by these assays . The name Enterococcus gilvus sp . nov . is proposed for strain PQ1, and the name Enterococcus pallens sp . nov . is proposed for strain PQ2 . Type strains have been deposited in culture collections as E . gilvus ATCC BAA-350 (CCUG 45553) and E . pallens ATCC BAA-351 (CCUG 45554).

J Infect Dis, 2002 Mar 15, 185(6), 766 - 73 Epub 2002 Feb 28.
The impact of persistent gastrointestinal colonization on the transmission dynamics of vancomycin-resistant enterococci; D'Agata EM et al.; The transmission dynamics of vancomycin-resistant enterococci (VRE) and factors contributing to their dissemination are complex . Mathematical modeling was used to simulate patterns of dissemination among patients and health care workers (HCWs) and to quantify the contribution of specific factors and infection control interventions on the endemic prevalence (EP) of VRE in a long-term hemodialysis unit . The model predicted that (1) an EP of 12% would be reached over time, regardless of the number of patients initially colonized, (2) endemicity would be sustained by the constant influx of newly colonized patients discharged from the hospital, (3) duration of VRE gastrointestinal colonization would have the most impact on the number of secondary cases, increasing the EP to a maximum of 70%, and (4) decreasing the patient:HCW ratio or improving hand hygiene would decrease the EP to 3% . Decreasing the duration of colonization, limiting hospital acquisition of VRE, and improving compliance with hand hygiene in the hemodialysis unit may decrease the rapidly rising rates of VRE in the patient population.

Bone Marrow Transplant, 2002 Mar, 29(5), 367 - 71
Antibiotic prophylaxis in patients receiving hematopoietic stem cell transplant; Sepkowitz KA; Effective prophylaxis against specific infections has allowed increasingly potent conditioning regimens to be given, thereby prolonging survival in HSCT recipients . The Centers for Disease Control and Prevention, in collaboration with numerous professional societies, has recently published guidelines to codify and advance this approach . Controversy remains in several areas but, curiously, the most intense debate concerns prevention of bacterial infections, the most extensively studied of all of the approaches . Central to this debate are the competing priorities of a potentially ill patient on the one hand vs the long-term consequences of unchecked antibiotic use . The emergence in the 1990s of vancomycin-resistant Enterococcus demonstrated all too vividly how devastating such an end result could be . This article will review the arguments for and against the routine use of antibacterial prophylaxis in HSCT recipients.

Infect Control Hosp Epidemiol, 2002 Mar, 23(3), 151 - 3
Characteristics of a large cluster of vancomycin-resistant enterococci in an Australian hospital; Cooper E et al.; Investigation of a cluster of hospital inpatients colonized with vancomycin-resistant enterococci (VRE) revealed a point-prevalence of 19.1% . The outbreak was controlled using established guidelines and additional strategies, including minimizing patient transfers and enforcing appropriate antibiotic prescribing . The incidence of VRE has remained low during the ensuing 30 months.

Fish Shellfish Immunol, 2002 Feb, 12(2), 97 - 109
The virulence of Enterococcus to freshwater prawn Macrobrachium rosenbergii and its immune resistance under ammonia stress; Cheng W et al.; Growth of pathogen bacterium . Enterococcus was not affected in tryptic soy broth (TSB) medium containing ammonia-N concentration in the range of 0-5.14 mg l(-1) . Giant freshwater prawn Macrobrachium rosenbergii (8-12 g) were challenged with Enterococcus which had been incubated for 24 h in TSB medium containing different concentrations of ammonia-N at 0-5.14 mg l(-1) Cumulative mortality of M . rosenbergii was higher for the bacteria incubated in TSB medium having ammonia-N at 0 and 0.26 mg l(-1), than those incubated in TSB medium having 1.28, 2.57 and 5.14 mg l(-1) ammonia-N after 24 h of challenge . However, cumulative mortality of prawn was significantly higher for the bacteria incubated in TSB medium with no ammonia added after 120 h of challenge . The prawns (8-12 g) were challenged with Enterococcus previously incubated in TSB medium for 24 h, then placed in water having concentrations of ammonia-N at control (0.06 mg l(-1)), 0.55, 1.01, 1.68 and 3.18 mg l(-1) . Mortality of prawns increased directly with ammonia-N concentrations after 72 h challenge . The pranws (20-30 g) which had been exposed to control, 0.55, 1.68 and 3.18 mg (-1) ammonia-N for 7 days were examined for the total haemocyte count (THC), differential haemocyte count (DHC), phenoloxidase activity and respiratory burst of haemocytes . Phenoloxidase activity decreased when the prawns were exposed to ammonia-N greater than 0.55 mg l(-1) . The respiratory burst increased significantly at 0.55 mg l(-1) but decreased significantly at 1.68 and 3.18mg (-1) ammonia-N . No significant difference in haemocyte count was observed among the prawns at different ammonia-N concentrations . It is suggested that ammonia in water decreases the virulence of Enterococcus, and reduces the immune resistance of M . rosenbergii.

Mol Microbiol, 1997 Jul, 25(1), 93 - 105
Mutations leading to increased levels of resistance to glycopeptide antibiotics in VanB-type enterococci; Baptista M et al.; The vanB gene cluster mediates glycopeptide resistance by production of peptidoglycan precursors ending in the depsipeptide D-alanyl-D-lactate (D-Ala-D-Lac) instead of D-Ala-D-Ala found in susceptible enterococci . Synthesis of D-Ala-D-Lac and hydrolysis of D-Ala-D-Ala is controlled by the VanR(B)S(B) two-component regulatory system that activates transcription of the resistance genes in response to vancomycin but not to teicoplanin . Two substitutions (A3C-->G or D168-->Y) in the VanS(B) sensor kinase resulted in induction by teicoplanin, indicating that the N-terminal domain of the protein was involved in glycopeptide sensing . A substitution (T237-->K) located in the vicinity of the putative autophosphorylation site of VanS(B) (H233) was associated with a constitutive phenotype and affected a conserved residue known to be critical for the phosphatase activity of related kinases . A mutant producing an impaired host D-Ala:D-Ala ligase required vancomycin for growth, since D-Ala-D-Lac was only produced under inducing conditions . The ddl and vanS(B) mutations, alone or in combination, resulted in various resistance phenotypes that were determined by the amount of D-Ala-D-Ala and D-Ala-D-Lac incorporated into peptidoglycan precursors under different inducing conditions.

APMIS, 2001 Nov, 109(11), 791 - 6
Mechanisms of resistance to imipenem in imipenem-resistant, ampicillin-sensitive Enterococcus faecium; El Amin N et al.; Enterococcus faecium has six penicillin-binding proteins (PBP), where PBP5 seems to be the main target for beta-lactam antibiotics . The PBP profiles of three imipenem-resistant, ampicillin-sensitive E . faecium strains, isolated from the same patient, were studied using biotinylated ampicillin and chemiluminescence detection . Imipenem resistance in these strains was found to be associated with hyperproduction of PBP5 compared to the ampicillin- and imipenem-susceptible strain ATCC 19434 . PBP5 in the imipenem-resistant strains (S1, B2) exhibited a selectively decreased affinity for imipenem . An 854 bp DNA fragment, corresponding to the penicillin-binding domain of pbp5fm, was studied in the resistant strains and the reference strain . Four amino acid substitutions were observed in the resistant strains compared to the susceptible one . The contribution of these substitutions to the increased production of PBP5 in these strains is unclear since the substitution was observed also in a strain without increased production of PBP5 . Our results suggest that the moderate imipenem resistance observed in these strains is associated with increased production of PBP5 with relatively decreased affinity for imipenem, and that evolution of imipenem resistance in E . faecium is dinstinct from that of the other beta-lactams such as ampicillin.

Infect Control Hosp Epidemiol, 2002 Feb, 23(2), 102 - 3
Risk factors for vancomycin-resistant Enterococcus (VRE) infection in colonized patients with cancer; Husni R et al.; To determine the risk factors for vancomycin-resistant Enterococcus (VRE) infection in colonized patients with cancer, we conducted a case-control study . According to multivariate analysis, the only significant factors were neutropenia (< 500 cells/mm3) for more than 1 week and the use of oral vancomycin . Therefore, colonized neutropenic patients with cancer who have previously used oral vancomycin are most prone to VRE infection.

Curr Opin Investig Drugs, 2001 Aug, 2(8), 1039 - 44
Oritavancin . Eli Lilly & Co; Barrett JF; Oritavancin (LY-333328), a lead glycopeptide from a series targeted at vancomycin-resistant bacteria, especially enterococci, is under development by Eli Lilly for the potential treatment of bacterial infections . It entered phase III trials in the US in January 2001 {396223} and the company expects to submit an NDA by 2003 {396478} . Oritavancin has been reported to have activity comparable to that of vancomycin and teicoplanin (Aventis Pharma AG), but retains activity against glycopeptide-resistant bacterial strains {407519} . The bactericidal activity of oritavancin suggests that it may prove useful as a single agent therapy in the treatment of antibiotic-resistant enterococci . Although its mechanism of action is unclear, dimerization of the glycosyl portion stabilizing D-Ala-D-Ala binding has been suggested {337644}.

Br J Haematol, 2002 Mar, 116(4), 826 - 33
Outbreak of vancomycin-resistant Enterococcus faecium in a haematology unit: risk factor assessment and successful control of the epidemic; Timmers GJ et al.; We describe an outbreak of vancomycin-resistant Enterococcus faecium (VRE) on the haematology ward of a Dutch university hospital . After the occurrence of three consecutive cases of bacteraemia with VRE, strains were genotyped and found to be identical . During the next 4 months an intensive surveillance programme identified 21 additional patients to be colonized with VRE, while two more patients developed bacteraemia . A case-control study was carried out to identify risk factors for VRE acquisition . In comparison with VRE-negative control patients (n=49), cases (n=24) had a longer stay on the ward during the year preceding the outbreak (25.8 versus 10.1 d, P=0.02), more cases with acute myeloid leukaemia {11 versus 4, odds ratio (OR) 9.5, 95% confidence interval (CI95) 2.4-32.2} and higher grades of mucositis (P=0.03) . Logistic regression analysis identified antibiotic use within 1 month before admission (OR 13.0, CI95 2.1-80.5, P=0.006) and low albumin levels at baseline (OR 1.2, CI95 1.1-1.3, P=0.02) to be independent risk factors . Four patients with VRE-bacteraemia were successfully treated with quinupristin/dalfopristin (Synercid) . Control of the outbreak was achieved by step-wise implementation of intensive infection control measures, which included the cohorting of patients, allocation of nurses and reinforcement of hand hygiene.

Int J Hyg Environ Health, 2002 Feb, 204(5-6), 309 - 16
Microbicidal efficacy of superheated steam . II . Studies involving E . faecium and spores of B . xerothermodurans and B . coagulans; Spicher G et al.; The authors' studies on the heat resistance of microorganisms and the superheating of steam (Spicher et al., Zbl . Hyg . Umweltmed . 201, 541-553, 1999) have been continued, using the vegetative bacterium, Enterococcus faecium, and spores of B . xerothermodurans and B . coagulans . The temperature of the saturated steam was 68 degrees C (E . faecium), 105 degrees C (B . xerothermodurans) and 110 degrees C (B . coagulans), respectively . The steam was superheated by 30-40 K, as a maximum . The test organisms had been fixed to fibre glass fleece . The time of exposure to saturated or superheated steam after which 50% of the bioindicators yielded no viable germs was used as a measure of resistance of the organisms . In the discussion, reference has also been made to the findings for B . subtilis and B . stearothermophilus spores obtained in the preceding study . E . faecium exhibited a maximum resistance when superheating the steam by 5 K . The superheated steam required a 74-fold exposure time compared to saturated steam of 68 degrees C . Resistance became gradually reduced as superheating was further increased . Even superheating by 30 K required a 11-fold exposure time . The bacterial spores exhibited maxima of resistance on superheating by 23-30 K . In these cases necessary exposure times were 119 (B . subtilis), 30 (B . xerothermodurans), and 4 times (B . coagulans, B . stearothermophilus) longer than those required in saturated steam . In the superheating range below 10 K, behaviour patterns varied . Thus, heat resistance may initially become reduced with increasing superheating (B . coagulans), remain on almost the same level as under exposure to saturated steam (B . stearothermophilus), reach a stage of weakly enhanced resistance (B . xerothermodurans), or approach a maximum of resistance in an almost linear mode (B . subtilis) . It appears that there are differences between strains of one and the same bacterial species.

Res Microbiol, 2002 Jan-Feb, 153(1), 27 - 32
Molecular cloning and functional characterisation of VanX, a D-alanyl-D-alanine dipeptidase from Streptomyces coelicolor A3(2); Tan AL et al.; The vanX gene which encodes a D-alanyl-D-alanine dipeptidase is critical for vancomycin resistance in enterococci . A putative vanX gene from Streptomyces coelicolor A3(2), which is not known for vancomycin production, was identified by homology-based analysis and cloned by polymerase chain reaction . The S . coelicolor vanX gene was heterologously expressed in Escherichia coli BL21(DE3) and enzymatic assays of soluble protein fractions of VanX revealed a 93-fold increase in dipeptidase activity as compared to the nonrecombinant control, thus confirming its functionality . Interestingly, S . coelicolor was also found to be of intermediate resistance to vancomycin although it does not produce vancomycin, thus suggesting the role of VanX in defence or immunity . As such, the prevalence of vanX genes in the environment may be more common than previously thought.

Clin Infect Dis, 2002 Apr 1, 34(7), 922 - 9 Epub 2002 Mar 04.
Clinical outcomes for patients with bacteremia caused by vancomycin-resistant enterococcus in a level 1 trauma center; Lodise TP et al.; To assess the degree of morbidity and mortality attributable to vancomycin resistance in enterococcal bacteremia (EB), a matched case-control study was conducted . Patients with bacteremia due to vancomycin-resistant enterococcus (VRE) were matched to control patients with bacteremia due to vancomycin-susceptible enterococcus . During 1996--2000, 65 patients with cases of clinically significant VRE bacteremia were identified, and 53 of these patients were successfully matched . In this group of patients, VRE bacteremia was found to be an independent predictor of crude mortality (odds ratio {OR}, 4.0; 95% confidence interval {CI}, 1.2--13.3) and the infection-related mortality rate (OR, 5.2; 95% CI, 1.4--20.0) . It was also an independent predictor of the rate of clinical failure at day 7 after the onset of EB (OR, 4.6; 95% CI, 1.2--17.3) and overall clinical failure (OR, 4.3; 95% CI, 1.3--14.5) and was associated with a longer mean length of hospitalization after the onset of EB, compared with that for control patients (22.7plus minus1.88 vs . 15.9 +/- 1.7, P=.006) . These observations indicate that vancomycin resistance in EB independently affects outcomes.

J Clin Microbiol, 2002 Mar, 40(3), 913 - 7
Enterococcus faecium-related outbreak with molecular evidence of transmission from pigs to humans; Lu HZ et al.; Between 24 July and 31 August 1998, thousands of domestic pigs died of hemorrhagic shock in three adjunct counties along the YangZi River in Jiangshu Province, China . From 28 July to 6 September 1998, 40 local farmers (36 males and 4 females, ages 23 to 78 years) were hospitalized with severe illness characterized by high fever, erythematous rash or petechiae, and profound lethargy after contact with sick pigs . Twelve (30%) of these patients died of respiratory failure and shock . Eleven bacterial isolates recovered from 11 blood and cerebrospinal fluid specimens collected from seven patients and two pigs were identified as Enterococcus faecium based on biochemical reactions and 16S rRNA gene sequence analysis . Both pig and human E . faecium isolates displayed indistinguishable antibiotic susceptibility and pulsed-field gel electrophoresis patterns . These data strongly suggest the spread of an outbreak of E . faecium-related sepsis from pigs to humans.

Microbes Infect, 2002 Feb, 4(2), 215 - 24
Antibiotic-resistant enterococci: the mechanisms and dynamics of drug introduction and resistance; Shepard BD et al.; Enterococci possess a vast array of mechanisms to resist the lethal effects of most antimicrobial drugs currently approved for therapeutic use in humans, thus presenting a considerable therapeutic challenge . This review summarizes current concepts regarding the mechanisms of resistance, as well as the emergence, proliferation, and epidemiology of resistant enterococci.

Appl Environ Microbiol, 2002 Mar, 68(3), 1381 - 91
Intraspecies genomic groups in Enterococcus faecium and their correlation with origin and pathogenicity; Vancanneyt M et al.; Seventy-eight Enterococcus faecium strains from various sources were characterized by random amplified polymorphic DNA (RAPD)-PCR, amplified fragment length polymorphism (AFLP), and pulsed-field gel electrophoresis (PFGE) analysis of SmaI restriction patterns . Two main genomic groups (I and II) were obtained in both RAPD-PCR and AFLP analyses . DNA-DNA hybridization values between representative strains of both groups demonstrated a mean DNA-DNA reassociation level of 71% . PFGE analysis revealed high genetic strain diversity within the two genomic groups . Only group I contained strains originating from human clinical samples or strains that were vancomycin-resistant or beta-hemolytic . No differentiating phenotypic features between groups I and II were found using the rapid ID 32 STREP system . The two groups could be further subdivided into, respectively, four and three subclusters in both RAPD-PCR and AFLP analyses, and a high correlation was seen between the subclusters generated by these two methods . Subclusters of group I were to some extent correlated with origin, pathogenicity, and bacteriocinogeny of the strains . Host specificity of E . faecium strains was not confirmed.

Lancet Infect Dis, 2001 Dec, 1(5), 314 - 25
Vancomycin-resistant enterococci: why are they here, and where do they come from?
Bonten MJ, Willems R, Weinstein RA.
Vancomcyin-resistant enterococci (VRE) have emerged as nosocomial pathogens in the past 10 years, causing epidemiological controversy . In the USA, colonisation with VRE is endemic in many hospitals and increasingly causes infection, but colonisation is absent in healthy people . In Europe, outbreaks still happen sporadically, usually with few serious infections, but colonisation seems to be endemic in healthy people and farm animals . Vancomycin use has been much higher in the USA, where emergence of ampicillin-resistant enterococci preceded emergence of VRE, making them very susceptible to the selective effects of antibiotics . In Europe, avoparcin, a vancomycin-like glycopeptide, has been widely used in the agricultural industry, explaining the community reservoir in European animals . Avoparcin has not been used in the USA, which is consistent with the absence of colonisation in healthy people . From the European animal reservoir, VRE and resistance genes have spread to healthy human beings and hospitalised patients . However, certain genogroups of enterococci in both continents seem to be more capable of causing hospital outbreaks, perhaps because of the presence of a specific virulence factor, the variant esp gene . By contrast with the evidence of a direct link between European animal and human reservoirs, the origin of American resistance genes remains to be established . Considering the spread of antibiotic-resistant bacteria and resistance genes, the emergence of VRE has emphasised the non-existence of boundaries between hospitals, between people and animals, between countries, and probably between continents.

Infect Control Hosp Epidemiol, 2002 Jan, 23(1), 43 - 4
Failure of oral antimicrobial agents in eradicating gastrointestinal colonization with vancomycin-resistant enterococci; Hachem R et al.; Eradication of gastrointestinal colonization with vancomycin-resistant enterococci (VRE) using a combination of oral bacitracin and gentamicin was evaluated . Twenty-eight evaluable treated patients were matched with 28 control patients . After 3 months of follow-up, 5 patients (18%) in the treatment group versus 1 patient (4%) in the control group (P = .2) had negative results on stool cultures, with a similar frequency of VRE bacteremia (P = .8) . The use of oral bacitracin plus gentamicin did not reduce VRE colonization or bacteremia.

Infect Control Hosp Epidemiol, 2002 Jan, 23(1), 19 - 22
Molecular typing and antimicrobial susceptibility of vancomycin-resistant Enterococcus faecium in Brazil; Cereda RF et al.; OBJECTIVES: To characterize vancomycin-resistant enterococci (VRE) isolates and to evaluate the mode of dissemination of this pathogen in Brazil . DESIGN: We collected 22 vancomycin-resistant Enterococcus faecium isolates from 6 medical centers in Sao Paulo, Brazil, and 1 isolate from a medical center in Curitiba, Brazil . PARTICIPANTS: All Brazilian hospitals that had identified vancomycin-resistant E . faecium up to the beginning of this study (late 1999) contributed isolates to the study . METHODS: The isolates were susceptibility tested using the broth microdilution method and the E-test . The presence of vancomycin resistance genes (vanA, vanB, vanC1, vanC2-3, and vanD) was evaluated by polymerase chain reaction; molecular typing was performed by pulsed-field gel electrophoresis (PFGE) . RESULTS: The vanA gene was demonstrated in all vancomycin-resistant E . faecium, except for 1 isolate . None of the vancomycin resistance genes cited above was detected in the isolate from Curitiba, which was the first vancomycin-resistant E . faecium described in Brazil . All isolates were resistant to ampicillin and teicoplanin . The main clone remains susceptible to doxycycline and chloramphenicol, but intermediate to quinupristin-dalfopristin . PFGE analysis demonstrated 7 major PFGE patterns . A unique PFGE pattern with 4 subtypes was detected in 17 isolates from 4 different hospitals . CONCLUSION: The results of our study indicate the occurrence of intra- and interhospital dissemination of VRE in Sao Paulo, Brazil.

Intern Med, 2002 Feb, 41(2), 133 - 7
Rapidly expanding lung abscess caused by Legionella pneumophila in immunocompromised patients: a report of two cases; Miyara T et al.; We describe two cases of lung abscess caused by Legionella pneumophila in immunocompromised patients . The first case had been treated initially with 60 mg prednisolone for ulcerative colitis, and L . pneumophila serogroup 1 was isolated from sputum samples after cavitation of the lung lesion . The second case was diagnosed as plasma cell lymphoma at post-mortem examination . L . pneumophila serogroup 5 was isolated from the contents of lung abscess, together with Enterococcus faecium and Prevotella intermedia in the post-mortem examination . Lung abscess caused by Legionella is unusual . Here, we discuss the difficulty of diagnosis of legionellosis in patients with unusual chest radiographic findings.

Clin Microbiol Infect, 1996 Mar, 1(3), 190 - 194
Reevaluation of contemporary laboratory methods for detection of antimicrobial resistance among enterococci; Cormican MG et al.; OBJECTIVE: To evaluate broth microdilution, disk diffusion, Etest and Vitek Systems for susceptibility testing of enterococci . METHODS: Susceptibility testing of a panel of 149 enterococci (99 vancomycin-resistant) strains, using the study methods, was performed and the results compared . RESULTS: For vancomycin susceptibility testing, categorical agreement of disk diffusion, Etest and Vitek with the reference broth microdilution test was > 95% . For aminoglycoside and ampicillin testing, categorical agreement between Etest and Vitek was 98 to 100% . CONCLUSIONS: Disk diffusion, Etest and Vitek have acceptable performance for detection of vancomycin resistance of Van A and Van B phenotypes among enterococci.

Diagn Microbiol Infect Dis, 2002 Feb, 42(2), 137 - 9
Linezolid-resistant Enterococcus faecium isolated from a patient without prior exposure to an oxazolidinone: report from the SENTRY Antimicrobial Surveillance Program; Jones RN et al.; A patient case report describes an Enterococcus faecium strain isolated from a blood culture that was resistant to linezolid (MIC, 8 microg/mL; G2576U mutation of 23S rRNA) . Co-resistances were identified for vancomycin, ampicillin, macrolides, fluoroquinolones, chloramphenicol, rifampin, gentamicin (high-level), nitrofurantoin and trimethoprim/sulfamethoxazole . Etest (AB BIODISK, Solna, Sweden) and disk diffusion results also detected the oxazolidinone resistance pattern . Laboratories should be aware of the rare possibility of these strains occurring during linezolid therapy or spontaneously (this case) in contemporary practice, and have in vitro susceptibility methods available capable of detecting oxazolidinone resistance.

Diagn Microbiol Infect Dis, 2002 Feb, 42(2), 91 - 7
Training costs and investment payback of implementing molecular diagnostics for identification of vancomycin resistant enterococci in a clinical microbiology laboratory; Page B et al.; Molecular diagnostics may be a more efficient method to manage resources; but most Microbiology laboratories have not introduced them into routine use due to the specialized training required . Using vancomycin resistant enterococci (VRE) screening during a comparison of a multiplex PCR (MPCR) and conventional biochemical testing (CBT) we studied 3 objectives: 1) to develop a molecular diagnostics in-house training program, 2) to assess the training program outcomes for competency and confidence, and 3) to determine laboratory payback . A training program for 14 technologists using multiple adult learning methods was implemented . Methods to minimize technical errors were introduced and included: use of a calibrated loop to deliver sample; prealiquotting reagents; increasing volume of specimen; addition of gel loading dye directly into reaction tubes; and establishment of an equivocal zone . In our laboratory MPCR costs $7.06 less than CBT, therefore the payback period for training and implementation would be approximately 3 years.

Crit Care Nurs Q, 2001 Aug, 24(2), 20 - 9
Emerging multiresistant organisms in the ICU: epidemiology, risk factors, surveillance, and prevention; Broadhead JM et al.; Recent cases of vancomycin-resistant enterococcus (VRE) at our facility and the emergence of new vancomycin intermediate resistant strains of bacteria provided the impetus for this discussion on superbugs . Each year approximately two million patients develop an infection after receiving health care in a United States hospital . These infections are often difficult to treat because the microorganisms most frequently involved are resistant to current antibiotic therapy . The result is increased morbidity, mortality, and health care costs . The recent development of intermediate resistant strains of bacteria is indeed an ominous indicator of what the future might hold for the health care profession should our current practices go on unchecked . This article will present an overview of the epidemiology of these multiresistant organisms, risk factors inherent to the intensive care environment, nursing responsibilities, and the rationale for surveillance protocols.

Crit Care Nurs Q, 2001 Aug, 24(2), 13 - 9
Applying social and behavioral theory as a template in containing and confining VRE; Curry VJ et al.; Infection control professionals play several important roles--surveyors, educators, and ultimately change agents--in the identification and prevention of nosocomial infections in hospitals . The medical and surgical intensive care units (ICUs) in a large inner-city teaching hospital experienced an increased patient colonization rate with vancomycin-resistant enterococcus (VRE) . Intervening in this problem required a multifaceted approach to control the spread of VRE and to change behavior by shifting social norms at multiple levels throughout the ICU community . The success of the interventions could be best explained by applying the use of several behavioral science models . The Ecological Model of Behavior Change, the Health Belief Model, and Social Cognitive Theory can be applied and are consistent with the successful interventions . This multifaceted approach to intervening in this problem consists of five levels of influence: (1) intrapersonal or individual factors, (2) interpersonal factors, (3) institutional factors, (4) community factors, and (5) public factors . We implemented educational inservices and developed references, policies, and programs directed at each of the five levels of influence . The Health Belief Model and Social Cognitive Theory were employed for intervention, and behavior change was based on modeling, observational learning, and vicarious reinforcement . Within six months of initial implementation, the number of positive VRE surveillance cultures and positive clinical isolates decreased significantly in both the medical and surgical ICUs . Two years later, there continues to be a marked reduction of VRE.

Clin Microbiol Infect, 1999 Jul, 5(7), 424 - 430
An interprovincial external quality assessment of the ability of Canadian laboratories to detect the vancomycin and penicillin resistance of Enterococcus faecium D366; Richardson H et al.; OBJECTIVE: To evaluate the ability of Canadian laboratories to identify enterococci and detect low-level resistance to penicillin, ampicillin and vancomycin in five provinces and two territories by two external quality assessment schemes . METHODS: Enterococcus faecium, strain D366, with minimum inhibitory concentrations for vancomycin and penicillin of 32 and 16 mg/L respectively, was distributed during a routine proficiency survey . Laboratories were required to culture and identify the isolate and to test antimicrobial susceptibility . Participants were assessed against consensus reference values . RESULTS: Three hundred and sixty-four hospital, commercial and public-health laboratories participated, using their established procedures for patient samples . The isolate was identified to the species level by 222 (61%) laboratories and to the genus level by a further 98 participants . Forty-four failed to meet the expected standard . Vancomycin resistance was detected by 94% . Those reporting a falsely susceptible result used disk diffusion testing . Penicillin resistance was noted by 250 of 258 laboratories reporting on this agent . An incorrect ampicillin-susceptible finding was reported by 62 of 147 laboratories using automated microdilution or agar dilution methods . CONCLUSIONS: Most laboratories identified the isolate to an appropriate level . Detection of low-level vancomycin and penicillin resistance was achieved by the majority . Ampicillin resistance was less readily detected.

Am J Infect Control, 2002 Feb, 30(1), 40 - 3
The effect of active surveillance for vancomycin-resistant enterococci in high-risk units on vancomycin-resistant enterococci incidence hospital-wide; Siddiqui AH et al.; BACKGROUND: Vancomycin-resistant enterococci (VRE) have become a major cause of nosocomial infections and are now endemic in many geographic areas . The aim of this study was to describe the effect of active surveillance for patients with VRE in high-risk units on the VRE incidence rate hospital-wide . METHODS: We determined 4 time periods based on the intervention of active surveillance: preactive surveillance (period 1), active surveillance (period 2), no active surveillance (period 3), and reinstutition of active surveillance (period 4) . VRE incidence rates based on first clinical culture for VRE per 10,000 patient days for each of these periods and incidence rate ratios were then calculated . RESULTS: Active surveillance in high-risk units was associated with a significant reduction in VRE incidence hospital-wide in 2 of the 3 comparisons made . The incidence rate ratio when comparing the first period of active surveillance (period 2) to the preactive surveillance period (period 1) was 0.63 (95% CI, 0.38-1.1); it was 0.36 (95% CI, 0.23-0.55) when comparing the first period of active surveillance (period 2) to the subsequent period (period 3) and 0.68 (95% CI, 0.54-0.85) when comparing the second period of active surveillance (period 4) to the prior period without active surveillance periods . CONCLUSIONS: Active surveillance culturing for VRE in the high risk-units prevented further VRE transmission, as evidenced by a significant increase in hospital-wide incidence rates when active surveillance was discontinued and a significant decrease in incidence rates when it was restarted.

Clin Microbiol Infect, 1999 Sep, 5(9), 554 - 559
MIC distribution and inoculum effect of LY333328: a study of vancomycin-susceptible and VanA-type and VanC-type enterococci obtained from intensive care unit patient surveillance cultures; Canton R et al.; OBJECTIVE: To determine the in vitro activity and inoculum effect of LY333328, a semisynthetic glycopeptide, against vancomycin-susceptible and vancomycin-resistant enterococcal isolates . METHODS: One hundred and seventy-six enterococcal isolates (117 vancomycin-susceptible, 29 VanA-type and 30 VanC-type isolates) obtained from surveillance cultures of 139 intensive care unit patients were studied by the standard agar dilution method . Vancomycin resistance determinants were characterized by PCR . RESULTS: The activity of LY333328 was comparable (MIC range, 0.1-2 mg/L) to those of vancomycin (0.1-4 mg/L) and teicoplanin (0.06-1 mg/L) for vancomycin-susceptible isolates . LY333328 was more active (0.1-8 mg/L) than vancomycin (256 to >1024 mg/L) and teicoplanin (32-512 mg/L) against VanA-type isolates, and similar (0.2-1 mg/L) to teicoplanin (0.1-0.5 mg/L) against VanC-type isolates . The MIC distribution of LY333328 displayed a narrower range than that of vancomycin, with no clear distinction between susceptible and resistant populations . The increment in the inoculum size, from 104 to 106 CFU/spot, of susceptible isolates increased the MIC values of LY333328, vancomycin and teicoplanin by factors of 11.4, 1.6 and 3.8, respectively . The corresponding factors for LY333328 for VanA-type and VanC-type isolates were 3.5 and 6.4, respectively . CONCLUSIONS: LY333328 displays an excellent in vitro activity against vancomycin-susceptible and -resistant enterococci . Nevertheless, the inoculum size used in susceptibility tests should be carefully controlled.

J Hosp Infect, 2002 Feb, 50(2), 140 - 4
Bactericidal activities of disinfectants against vancomycin-resistant enterococci; Sakagami Y et al.; The bactericidal activities of 35 commercially available disinfectants against vancomycin-resistant enterococci (VRE) and vancomycin-sensitive enterococci (VSE) were investigated under both clean and dirty (albumin added) conditions using a microtitration plate method . No differences in bactericidal time were observed with any of the test disinfectants when comparing activity against VRE or VSE . Isopropyl alcohol (70 v/v%), alcohol-containing preparations such as Welpas, Wellup and Maskin W . ethanol solution, 0.2% of cation surfactant disinfectants such as Osvan solution 'daigo', Germitol 'Maruishi' 10% and Hyamine solution, and 0.5% of amphoteric compound disinfectants such as TEGO-51, Hygieel and Hypal No.3, were the most effective compounds when compared with other disinfectants.These results suggest that the use of a disinfectant with activity against VRE may be one appropriate method for preventing infections caused by this micro-organism .

J Clin Nurs, 2002 Jan, 11(1), 126 - 33
Nurses' experience with vancomycin-resistant enterococci (VRE); Mitchell A et al.; The emergence and spread of resistant organisms, in particular vancomycin-resistant enterococci (VRE), is an issue facing all staff in acute hospitals . This study explored how nurses coped with the responsibility of halting further spread of this organism during an outbreak . VRE-positive patients were cohorted with nurses who cared for them in an endeavour to contain the spread of VRE . The majority of nurses found the situation extremely stressful because of the need to act as 'gatekeepers' responsible for educating and monitoring the practices of staff and visitors . The nurses reported that they felt they were inadequately supported, were blamed for the outbreak, and that they had an increased workload as they took on duties of other staff . The results reinforce the need for a multidisciplinary team approach to education and control of VRE, more support for nursing staff cohorted with VRE-positive patients, and stringent adherence to infection control measures by all hospital staff.

Int J Food Microbiol, 2002 Jan 30, 72(1-2), 125 - 36
Bacteriocin production by Enterococcus faecium FAIR-E 198 in view of its application as adjunct starter in Greek Feta cheese making; Sarantinopoulos P et al.; Bacteriocin production by Enterococcus faecium FAIR-E 198, isolated from Greek Feta cheese, was studied in batch fermentations, under conditions simulating Feta cheese preparation . Maximum enterocin activity and growth rate was obtained in de Man-Rogosa-Sharpe (MRS) broth at 37 degrees C with controlled pH 6.5 . The enterocin was produced throughout the growth phase of the microorganism, showing primary metabolite kinetics with a peak activity during the mid-exponential phase . The use of skimmed milk as substrate revealed low enterocin activity . When fermentations were performed in skimmed milk in the presence of rennet, CaCl2, and a mixed starter culture, no enterocin activity was observed, although the examined strain grew well under the above conditions . Finally, when E . faecium FAIR-E 198 was applied as adjunct starter in Feta cheese making, no enterocin activity was detected throughout ripening . Results obtained underline the frequently underestimated finding that in vitro production by novel bacteriocinogenic starter or co-cultures is no guarantee for in situ efficiency . It was concluded that the complex food environment thoroughly interferes with bacteriocin production levels.

Water Sci Technol, 2002, 45(1), 67 - 74
The effect of pH on enterococci removal in Pistia-, duckweed- and algae-based stabilization ponds for domestic wastewater treatment; Awuah E et al.; A batch scale experiment was conducted to determine the effect of pH on enterococci die-off . A continuous flow system was also established to determine the environmental conditions and their effects on enterococci removal . The batch experiment was conducted for pHs: 4, 5, 7, 9, and 11 under light and dark conditions . Enterococci and DO were measured every day and every other day respectively for nine days . Pathogen removal rates at pH 4, 5, 7, 9 and 11 in the light/dark were (expressed as d(-1)) -2.1/-2.1, -2.1/-1.5, -2.1/-1.5, -2.1/-1.4 and -1.1/-1.0, respectively . DO levels were low, between 0.17 mg/L at pH 4 (light) to 0.56 mg/L at pH 7 (light) . The continuous flow system consisted of Pistia (water lettuce), duckweed and algal treatments in series of four ponds with a total retention period of 28 days after two days of anaerobic pre-treatment . After two months of operation, temperature, pH, DO, TDS, and enterococci populations were monitored . A low pH of 4.4 was obtained in the Pistia ponds . Neutral conditions were observed in the duckweed system, while pH values >9 were observed in the algal system . Enterococci decreased from 7.8 x 10(6) to <500/100 ml in all treatment systems after 28 days of treatment with no significant differences between treatments.

Nippon Geka Gakkai Zasshi, 2001 Dec, 102(12), 851 - 5
{Guidelines for adequate antibiotic prophylaxis after hepatic, biliary, and pancreatic surgery}; Kobayashi Y et al.; The recent spectrum of bacteria isolated from patients with hepatic, biliary, and pancreatic infections mostly consists of Gram negative rods translocated from their intestinal flora . Cephem or carbapenem antibiotics should be selected based on the severity of surgical infection and risk to each patient to prevent postoperative infections . Once postoperative infection occurs, surgical procedures such as ultrasonography-guided percutaneous biliary drainage should be performed to reduce inflammation and to obtain samples for bacterial culture . The most commonly identified bacteria after hepatic, biliary, and pancreatic surgery are Pseudomonas species, MRSA, and Enterococcus species . Previously administered antimicrobial agents should be immediately interrupted and empiric antibiotic therapy with carbapenem started . Vancomycin or teicoplanin is selected when MRSA or Enterococcus faecium infection is suspected . Infection control systems should be in place for prevention of postoperative MRSA infections.

Int J Antimicrob Agents, 2002 Jan, 19(1), 39 - 46
Differential antimicrobial susceptibility between human and chicken isolates of vancomycin-resistant and sensitive Enterococcus faecium; Chen HY et al.; To compare the differential antimicrobial susceptibilities of Enterococcus faecium from humans and whole chicken carcasses, MICs of 12 antimicrobial agents were determined for 54 clinical-isolates (31 vancomycin-resistant {VREF}) and 60 chicken-isolates (29 VREF) . Chicken VREF were slightly but consistently more resistant to vancomycin, teicoplanin and avoparcin, compared with human VREF (P<0.01) . MICs of LY333328 were <or = 2 mg/l . All human VREF were resistant to erythromycin and tylosin, compared with only 58.6% of chicken VREF (P<0.01) . Streptogramins were active against all isolates except four chicken strains . MIC(90s) of amoxycillin and gentamicin for human E . faecium were 8-16-fold higher than chicken isolates . Chicken VREF were significantly more resistant to tetracycline but more susceptible to chloramphenicol than human VREF (P<0.001).

J Inorg Biochem, 2002 Jan 15, 88(2), 192 - 6
Role for zinc(II) in the copper(I) regulated protein CopY; Cobine PA et al.; Despite the importance of copper-thiolate clusters in the regulation of copper metabolism the formation chemistry of these clusters in proteins is not well understood . The number of Cu(I) ions that can be incorporated within a given molecule and their coordination number varies . CopY is a repressor protein from Enterococcus hirae which utilises a copper-thiolate cluster in the regulation of the copper homeostasis genes . Physical, biological assays of purified native reconstituted apoCopY suggest that the formation of a Zn(II)-protein prior to Cu(I) incorporation is necessary to achieve the native Cu(I)-S cluster . In this protein the Zn(II) is readily displaced by the Cu(I) . CopY proteins with homologous metal binding motifs are being used to investigate cluster formation stabilisation.

Crit Care Med, 2001 Dec, 29(12), 2383 - 5
Successful treatment of vancomycin-resistant enterococcus meningitis with linezolid: case report and review of the literature; Steinmetz MP et al.; OBJECTIVE: To describe the successful treatment of a case of vancomycin-resistant enterococcus meningitis with linezolid . DESIGN: Case report and review of the literature . PATIENTS: The patient is a 35-yr-old man who suffered a cerebellar hemorrhage after embolization of a cerebellar arteriovenous malformation . The patient underwent ventriculostomy drainage and craniectomy . The patient was on broad-spectrum antibiotics for pneumonia including vancomycin . The patient remained febrile and grew vancomycin-resistant Enterococcus faecium from the cerebrospinal fluid . INTERVENTIONS: The patient was treated with intravenous chloramphenicol without success . On postoperative day 16, the patient was begun on intravenous linezolid . MAIN RESULTS: The patient received 4 wks of intravenous linezolid with complete eradication of the meningitis . CONCLUSIONS: Intravenous linezolid appears to be a safe and effective therapy for vancomycin-resistant enterococcus meningitis.

Clin Infect Dis, 2002 Feb 15, 34(4), 441 - 6 Epub 2002 Jan 07.
Patients in long-term care facilities: a reservoir for vancomycin-resistant enterococci; Elizaga ML et al.; A prospective cohort study with culture surveys and chart reviews was conducted to determine the prevalence of rectal colonization with vancomycin-resistant enterococci (VRE) and to identify risk factors for colonization among 100 residents of 20 different long-term care facilities (LTCFs) who were admitted to 2 medical wards of an academic acute care hospital . On admission to the hospital, 45 (45%) of these 100 patients were determined to be harboring VRE . Prior use of antibiotics and the presence of a decubitus ulcer were identified as risk factors . Fourteen other LTCF residents-33% of those at risk-acquired VRE in the hospital . Antecubital skin colonization with VRE was detected in 28% of patients . Hospital ward surveillance revealed a 60% mean point prevalence of VRE colonization among patients in LTCFs, compared with 21% for other patients (P<.001) . Patients in LTCFs in urban referral hospitals are a major reservoir for VRE, which can be transmitted to other inpatients in the hospital, in the LTCF, and in smaller community hospitals.

Antimicrob Agents Chemother, 2002 Feb, 46(2), 525 - 7
Vancomycin-resistant enterococci from humans and retail chickens in Taiwan with unique VanB phenotype-vanA genotype incongruence; Lauderdale TL et al.; Vancomycin resistant enterococci (VRE) with VanB phenotype-vanA genotype incongruence were found in all 39 VRE isolated from chicken carcasses and four human VRE isolates in Taiwan . Three identical mutations in the vanS gene were found in the VanB phenotype-vanA genotype VRE sequenced . This finding indicates possible transmission of glycopeptide resistance among different hosts.

Clin Neurol Neurosurg, 2002 Jan, 104(1), 54 - 6
Successful treatment of ventriculostomy-related meningitis caused by vancomycin-resistant Enterococcus with intravenous and intraventricular quinupristin/dalfopristin; Williamson JC et al.; We report a case of ventriculostomy-related meningitis caused by vancomycin-resistant Enterococcus faecium (VRE) . The patient was successfully treated with administration of quinupristin/dalfopristin by both intravenous and intraventricular routes . A brief review of the literature is provided, which indicates that optimal management with quinupristin/dalfopristin should include daily intraventricular doses of at least 2 mg.

Water Res, 2001 Dec, 35(17), 4243 - 6
Development of glucosidase agar for the confirmation of water-borne Enterococcus; Adcock PW et al.; Analysis of 56 river water samples by the Enterolert defined substrate technique, and standard m-Enterococcus agar isolation followed by confirmation, indicated that after 24 h incubation . Enterolert significantly underestimated the true numbers of enterococci . Extending Enterolert incubatioin to 36 h improved detection but also revealed false positives . These findings prompted the development of a novel confirmation medium we have termed glucosidase agar, which was prepared by dissolving Enterolert substrate in 2% (w/v) bacteriological agar . Analysis of 1,043 colonies arising on m-Enterococcus agar from 280 freshwater, marine and sewage effluent samples, demonstrated that 2-4 h incubation on glucosidase agar was a rapid and accurate means of confirming presumptive enterococci, when compared to standard confirmation procedures that take 48 h . The combination of primary isolation on m-Enterococcus agar followed by confirmation on glucosidase agar permits maximum recovery of Enteroccus whilst effectively eliminating false positives/negatives and provides a reliable alternative use of the Enterolert defined substrate technology.

Biochem Biophys Res Commun, 2002 Jan 11, 290(1), 558 - 62
Salt resistance and synergistic effect with vancomycin of alpha-helical antimicrobial peptide P18; Shin SY et al.; P18 (KWKLFKKIPKFLHLAKKF-NH(2)) is an alpha-helical antimicrobial peptide designed from a cecropin A-magainin 2 hybrid . In this study, P18 was found to show strong antimicrobial activity against several antibiotic-resistant bacterial and fungal strains . Both the salt resistance on antimicrobial activity and the synergistic effect with clinically used antibiotic agents are critical factors in developing effective peptide antibiotic drugs . For this reason, we investigated the salt resistance of P18 to antagonism by NaCl, CaCl(2), and MgCl(2) on antimicrobial activity and the synergistic effect of P18 with vancomycin against vancomycin-resistant Enterococcus faecium (VREF) . Compared to magainin 2, P18 showed strong resistance on antimicrobial activity against bacterial strains and C . albicans under high NaCl concentrations of 100-200 mM . In addition, P18 displayed much greater salt resistance on antibacterial activity against Gram-negative bacteria at the physiological or elevated concentrations of CaCl(2) and MgCl(2) than magainin 2 . Furthermore, the combination study revealed that P18 has a relatively effective synergistic effect with vancomycin against VREF . Thus, these results support that P18 may prove to be a salt-resistant antibiotic peptide potentially useful in the treatment of cystic fibrosis patients as well as a valuable adjuvant for antimicrobial chemotherapy . (c)2002 Elsevier Science.

Zhonghua Jie He He Hu Xi Za Zhi, 2000 Jul, 23(7), 413 - 6
{High risk factors lead to noscomial pulmonary infections caused by MRSA}; Wu B et al.; OBJECTIVE: To investigate major risk factors leading to death by noscomial MRSA pulmonary infections . METHOD: The data of hospitalized patients diagnosed as noscomial MRSA pulmonary infections were sorted out and analyzed for recent three years . RESULTS: Case mortality of 64 patients with noscomial MRSA pulmonary infections were 44% . Of these, 18 cases complicated fungi, 11 Klebsiella pneumoniae, 9 Pseudomonas maltophilia and 7 Enterococcus . Case mortality of fungi and Pseudomonas maltophilia were 67% and 61%, respectively . 23 cases had fever, 18 died (case mortality 78%) and 41 had no fever, 10 died (case mortality 24%) (chi 2 = 15.253, P < 0.005) . The case mortality with reduction, normal and increase of leukocyte were 80%, 24% and 45%, respectively . The comparison between three groups had obvious significance (chi 2 = 12.554, P < 0.005) and the case mortality of leukocytopenia was higher than that of other two groups (chi 2 = 8.626, P < 0.005) . The case mortality of hypoproteinemia was higher than that of the control group (chi 2 = 6.914, P < 0.01) . The patients who developed fulminant lesions in liver, kidneys and lungs showed higher mortality rate . CONCLUSIONS: Case mortality of noscomial pneumonia caused by MRSA is very high . In addition to common causes, underling diseases, leukocytopenia, malnutrition and complex infections are also risk factors of MRSA infection.

Diagn Microbiol Infect Dis, 2001 Dec, 41(4), 215 - 20
Effect of routine use of a multiplex PCR for detection of vanA- and vanB- mediated enterococcal resistance on accuracy, costs and earlier reporting; Petrich A et al.; A multiplex PCR (MPCR) for detection of vanA-and vanB-mediated resistance to vancomycin was optimized and adapted for use in the routine microbiology laboratory . Consecutive specimens (1196) submitted for vancomycin resistant Enterococci (VRE) surveillance were processed by clinical technologists on Bile Esculin Azide Agar containing 6 mg/L vancomycin (BEAA/Vanco6) plates and 466 showing black colony growth were processed by conventional biochemical testing (CBT) and by MPCR . CBT identified 208 VRE positives . MPCR detected 205 of the CBT- positives plus an additional 10 . Analysis of the discordant specimens determined that 5 CBT- negative/MPCR-positive specimens also contained Enterococci with vanC resistance, 3 CBT-positive/MPCR-negative specimens were true positives, and 5 CBT-negative/MPCR-positive specimens occurred due to technical error . The sensitivity and specificity of MPCR were 98.4% and 96.1% . MPCR identifications of VRE were achieved approximately 48 h earlier than CBT and at 60% of the costs.

Infect Control Hosp Epidemiol, 2001 Oct, 22(10), 624 - 9
Risk factors for colonization with vancomycin-resistant enterococci in a Melbourne hospital; MacIntyre CR et al.; OBJECTIVE: To determine risk factors for colonization with vancomycin-resistant enterococci (VRE) in a hospital outbreak . DESIGN: Outbreak investigation and case-control study . SETTING: A referral teaching hospital in Melbourne, Australia . PARTICIPANTS: Cases were inpatients colonized (with or without clinical disease) with VRE between July 26 and November 28, 1998; controls were hospitalized patients without VRE . METHODS: Five cases of VRE were identified between July 26 and November 8, 1998, by growth of VRE from various sites . Active case finding by cultures of rectal swabs from patients surveyed in wards was commenced on July 26, after the first isolate of VRE . RESULTS: There were 19 cases and 66 controls . All the VRE identified were vanB, and all were Enterococcus faecium . One molecular type predominated (18/19 cases) . In a logistic-regression model, being on the same ward as a VRE case was the highest risk factor (odds ratio {OR}, 82; 95% confidence interval {CI95}, 5.7-1,176; P=.001) . Having more than five antibiotics (OR, 11.9; CI95 1.1-129.6; P<.05), use of metronidazole (OR, 10.9; CI95, 1.7-69.8; P=.01), and being a medical patient (OR, 8.1; CI95, 1.4-47.6; P<.05) also were significant . Intensive care unit admission was associated with decreased risk (OR, 0.1; CI95, 0.01-0.8; P<.05) . CONCLUSION: Our findings are consistent with an acute hospital outbreak . Monitoring and control of antibiotic use, particularly metronidazole, may reduce VRE in our hospital . Ongoing surveillance and staff education also are necessary.

Am Fam Physician, 2001 Dec 1, 64(11), 1863 - 6
Quinupristin-dalfopristin: a new antibiotic for severe gram-positive infections; Manzella JP; The steady increase in resistant organisms is related to the widespread use of antibiotics in community and hospital settings . New therapeutic options are needed, including treatments for infections caused by antibiotic-resistant gram-positive organisms . Quinupristin-dalfopristin, the first formulation of a distinct class of antibiotics known as the streptogramins, has activity against a range of gram-positive bacteria that are usually resistant to other agents, including vancomycin-resistant Enterococcus faecium . The pharmacodynamic (postantibiotic effect) and pharmacokinetic characteristics of quinupristin-dalfopristin allow dosing at eight- to 12-hour intervals . The safety profile of the formulation is generally favorable, with no demonstrable ototoxicity, nephrotoxicity, bone marrow suppression, or cardiovascular adverse effects . Reversible arthralgias, myalgias, and peripheral venous irritation are the formulation's major side effects . A potential for drug interactions exists because quinupristin-dalfopristin significantly inhibits the cytochrome P450-3A4 enzyme system . Quinupristin-dalfopristin has been shown to be effective in the management of documented severe infections caused by vancomycin-resistant E . faecium, nosocomial pneumonia, and infections related to the use of intravascular catheters.

Int J Food Microbiol, 2001 Nov 8, 70(3), 291 - 301
Biochemical and genetic evidence for production of enterocins A and B by Enterococcus faecium WHE 81; Ennahar S et al.; Enterococcus faecium WHE 81, isolated from cheese, has been reported to produce a bacteriocin called "enterocin 81" {J . Appl . Microbiol . 85 (1998) 521.} . Purification of "enterocin 81" was carried out using ammonium sulfate precipitation, desalting on ODP-90 reverse-phase column, and purification through SP Sepharose HP cation exchange and C2/C18 reverse-phase chromatographies . The antimicrobial was eluted from the C2/C18 column as four individually active fractions, designated A81, B81, C81 and D81 . The purification procedure used proved particularly efficient for the bacteriocin in fraction D81, with a yield of 46%, while only 3.8% the bacteriocin in fraction B81 could be collected . MALDI-TOF mass spectrometry of the bacteriocins in fractions B81 and D81 showed respective masses of 4,833.0 and 5,462.2 Da . Amino acid sequencing of the two peptides revealed two class-II bacteriocins whose sequences were similar to those of enterocin A and enterocin B, respectively . Using proper primers, chromosomal fragments of 212 and 216 bp enclosing bacteriocin structural genes were PCR-amplified . Cloning of the amplicons and their sequencing revealed two genes with sequences identical to the structural genes of enterocins A and B, respectively . It was therefore clearly established that E . faecium WHE 81 produces bacteriocins respectively identical to enterocins A and B . Our results, combined with data from previous reports, suggest that the two bacteriocins may be widespread among enterococcal strains and may play an important role in controlling the growth of pathogens and other undesirable bacteria in certain fermented food products.

Ned Tijdschr Geneeskd, 2001 Nov 24, 145(47), 2264 - 70
{Clinical thinking and decision making in practice . 4 times ERCP, 6 times ultrasonography of the upper abdomen and 3 CT-scans for a woman with recurrent fever and bacteremia}; Rompelman SE et al.; A 42-year-old woman was hospitalised due to recurrent fever (40 degrees C) and bacteraemia . A physical examination revealed no abnormalities . Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca and Enterococci were found in blood cultures . Laboratory results revealed liver enzyme levels which were only slightly elevated . An X-ray investigation, ERCPs, CT scans, ultrasounds, a leucocyte scintigram and a gallium scan, all revealed no abnormalities . Due to the results from the blood cultures it was thought that the bile duct system or the digestive tract were the focus of infection . Therefore a liver biopsy was carried out for the purpose of making a diagnosis . The patient was diagnosed as having ductal plate malformation, a microscopic congenital cystic dilatation of the bile ducts . The prognosis is poor and the treatment consists of lifelong antibiotics.

Med Dosw Mikrobiol, 2001, 53(2), 111 - 6
{Growth of enterococci in normal and iron saturated serum}; Lisiecki P et al.; Among 20 strains of genus Enterococcus isolated from different sources 12 strains multiplied in iron unsupplemented normal human serum . The excess of iron did not increase the rate of multiplication . Three strains survived in serum and growth of five strains was inhibited . The siderophores production had no effect on the multiplication of enterococci in serum unsupplemented with iron.

Med Dosw Mikrobiol, 2001, 53(1), 9 - 15
{Animal body iron sources utilized in vitro by enterococci}; Sobis-Glinkowska M et al.; Under iron restricted conditions enterococcal strains could utilize in vitro several animal body iron sources in form of bovine hemoglobin, hemin, lactoferrin and transferrin, ovotransferrin, horse myoglobin, ferritin and cytochrome C . Spectrum of utilized iron sources was not depended on species affiliation and origin of strains.

Med Dosw Mikrobiol, 2001, 53(1), 1 - 7
{Hydroxamate siderophore effect on growth of enterococci}; Sobis-Glinkowska M et al.; In eleven strains of genus Enterococcus relation between hydroxamate siderophore production and growth in iron-restricted liquid medium was investigated . Fe(III) deficiency caused moderate decrease of growth rate: the exponential growth phase was prolonged and yield of bacterial mass was lower . The hydroxamate siderophore was produced by all strains but occurred at different phase of growth . Only part of strains showed classical pattern of growth kinetic and siderophore synthesis.

Z Gastroenterol, 2001 Dec, 39(12), 985 - 92
{Interventional ERCP in patients with cholestasis . Degree of biliary bacterial colonization and antibiotic resistance}; Kiesslich R et al.; Interventional ERCP in patients with cholestasis . Degree of biliary bacterial colonization and antibiotic resistance.Biliary obstruction together with bacterial colonization of the bile duct may lead to development of acute cholangitis . The aim of our prospective study was to investigate the presence and degree of biliary bacterial colonization by means of bile aspiration during ERCP in patients with biliary obstruction . Furthermore, we evaluated antibiotic therapy regimens, which would cover the bacterial species obtained by ERCP and subsequent culture in each patient . In addition, analysis of risk factors was performed that would predispose to the development of cholangitis.80 patients with clinical and laboratory evidence of biliary obstruction underwent ERCP with initial aspiration of bile via the cannulation catheter.This material was used to culture aerobic and anaerobic bacteria and determine the colony count/ml bile, followed by identification of each species and antibiotic resistance testing . The minimal inhibitory concentration for Levofloxacin, Ciprofloxacin, Piperacillin, Ampicillin, Ceftriaxone, Imipenem, Gentamycin und Metronidazole was determined . Immediately after the ERCP or if the body temperature (after ERCP) rose to > 38 degrees C blood cultures were obtained.In 45 (56 %) patients biliary colonization with bacteria could be identified (56 %) . In 20 patients a single isolate was cultured, in 25 cases mixed infection was present . A total of 83 species were isolated . The most common bacteria were E . coli, Enterococcus and Klebsiella . 9.6 % of all isolates were obligatory anaerobes . In 9 of 80 patients bloodcultures tested positive for bacterial growth (rate of bacteremia: 11.3 %) . 10 patients had acute cholangitis clinically before ERCP, 13 patients developed signs of infection after ERCP.Statistically significant factors contributing to the risk of infection were age of the patient, the clinical condition of the patient before ERCP and the biliary colony count.Patients with development of infection after ERCP showed a significantly higher incidence of bacterial colonization of the biliary tree and a higher colony count.In all bacterial species Imipenem (4.5 %) or Levofloxacin (2.2 %) exhibited the lowest rate of in-vitro resistance.Based on these data, the implementation of Levofloxacin in combination with anaerobic coverage is advantageous as a calculated therapy for patients with acute cholangitis.

Infect Immun, 2002 Jan, 70(1), 204 - 10
Bacteriophage therapy rescues mice bacteremic from a clinical isolate of vancomycin-resistant Enterococcus faecium; Biswas B et al.; Colonization of the gastrointestinal tract with vancomycin-resistant Enterococcus faecium (VRE) has become endemic in many hospitals and nursing homes in the United States . Such colonization predisposes the individual to VRE bacteremia and/or endocarditis, and immunocompromised patients are at particular risk for these conditions . The emergence of antibiotic-resistant bacterial strains requires the exploration of alternative antibacterial therapies, which led our group to study the ability of bacterial viruses (bacteriophages, or phages) to rescue mice with VRE bacteremia . The phage strain used in this study has lytic activity against a wide range of clinical isolates of VRE . One of these VRE strains was used to induce bacteremia in mice by intraperitoneal (i.p.) injection of 10(9) CFU . The resulting bacteremia was fatal within 48 h . A single i.p . injection of 3 x 10(8) PFU of the phage strain, administered 45 min after the bacterial challenge, was sufficient to rescue 100% of the animals . Even when treatment was delayed to the point where all animals were moribund, approximately 50% of them were rescued by a single injection of this phage preparation . The ability of this phage to rescue bacteremic mice was demonstrated to be due to the functional capabilities of the phage and not to a nonspecific immune effect . The rescue of bacteremic mice could be effected only by phage strains able to grow in vitro on the bacterial host used to infect the animals, and when such strains are heat inactivated they lose their ability to rescue the infected mice.

Emerg Infect Dis, 2001 Nov-Dec, 7(6), 1030 - 1
Absence of high-level vancomycin resistance in enterococci isolated from meat-processing facilities; Bodnaruk PW et al.; Enterococci isolated from packaging areas of meat-processing facilities that produce ready-to-eat meat products were examined for high-level vancomycin resistance . A total of 406 enterococci isolates from the plants' packaging areas were examined for vancomycin resistance . High-level vancomycin resistance was not demonstrated in any enterococci isolated from 12 meat-processing plants.

J Infect Dis, 2001 Dec 15, 184(12), 1624 - 7 Epub 2001 Dec 03.
Inhibition of vancomycin-resistant enterococci by an in vitro continuous-flow competitive exclusion culture containing human stool flora; Donskey CJ et al.; An in vitro anaerobic continuous-flow competitive exclusion (CFCE) culture model was used to study the ability of human stool flora to inhibit the growth of vancomycin-resistant (VR) enterococci (VRE) . The CFCE culture was established from a stool sample obtained from a healthy adult . When 10(3) or 10(6) cfu/mL of VR Enterococcus faecium were added to the CFCE culture, the VRE were eliminated within 6 or 9 days, respectively . When 10(7) cfu/mL of the CFCE culture was added to a continuous-flow culture that contained 10(7) cfu/mL of VRE, the density of VRE was reduced but not eliminated . These data support the hypothesis that the indigenous intestinal flora inhibit growth of VRE and suggest that CFCE cultures may be a useful means to study interactions between the indigenous flora and VRE.

Clin Infect Dis, 2002 Jan 15, 34(2), 167 - 72 Epub 2001 Dec 04.
High rate of false-negative results of the rectal swab culture method in detection of gastrointestinal colonization with vancomycin-resistant enterococci; D'Agata EM et al.; The diagnostic accuracy of the rectal swab (RS) culture method in identifying gastrointestinal colonization with vancomycin-resistant enterococci (VRE) is not known . Serial quantitative stool cultures, skin cultures, and RS cultures were performed for patients with VRE infections to assess the false-negative rate of the RS and the prevalence of skin colonization, a prerequisite for cross-transmission, at varying VRE stool densities . A total of 35 stool samples were obtained from 13 patients . The sensitivity of the RS culture was 58%; it ranged from 100%, at VRE densities of > or =7.5 log10 colony forming units (cfu) per gram of stool, to 0%, at densities of < or =4.5 log10 cfu per gram of stool . Skin colonization was detected at these low VRE stool densities, but it was more common at higher VRE densities (P<.001) . Antibiotic exposure was significantly associated with higher VRE stool densities (P<.001) . The high false-negative rate of the RS may be contributing to the continued increase in the prevalence of VRE.

Clin Infect Dis, 2002 Jan 15, 34(2), 159 - 66 Epub 2001 Dec 07.
Enterococcal endocarditis in Sweden, 1995-1999: can shorter therapy with aminoglycosides be used?
Olaison L, Schadewitz K; Swedish Society of Infectious Diseases Quality Assurance Study Group for Endocarditis.
A 5-year nationwide prospective study in Sweden during 1995-1999 identified 881 definite episodes of infective endocarditis . Definite enterococcal endocarditis was diagnosed in 93 episodes (11%), the largest series of enterococcal endocarditis so far presented . Mortality during treatment was 16%, the relapse rate was 3%, and clinical cure was achieved in the remaining 81% of the episodes . Clinical cure was achieved with a median duration of cell wall-active antimicrobial therapy of 42 days combined with an aminoglycoside (median treatment time, 15 days) . International guidelines generally recommend a 4-6-week combined synergistic treatment course with a cell wall-active antibiotic and an aminoglycoside . Treatment regimens in Sweden often include a shortened aminoglycoside treatment course in order to minimize adverse effects in older patients . Fatal outcome seemed not to be due to the shortened aminoglycoside therapy course . In many enterococcal endocarditis episodes, duration of aminoglycoside therapy could probably be shortened to 2-3 weeks.

Infect Control Hosp Epidemiol, 2001 Sep, 22(9), 560 - 4
Contamination of gowns, gloves, and stethoscopes with vancomycin-resistant enterococci; Zachary KC et al.; OJECTIVE: To measure directly the rate of contamination, during routine patient examination, of gowns, gloves, and stethoscopes with vancomycin-resistant enterococci (VRE) . SETTING: A large, academic, tertiary-care hospital . PATIENTS: Between January 1997 and December 1998, 49 patients colonized or infected with VRE were entered in the study . DESIGN: After routine examination, the examiner's glove fingertips, gown (the umbilical region and the cuffs), and stethoscope diaphragm were pressed onto Columbia colistin-nalidixic acid (CNA) agar plates with 5% sheep blood plus vancomycin 6 pg/mL . The stethoscope diaphragm was sampled again after cleaning with a 70% isopropanol wipe . RESULTS: VRE were isolated from at least 1 examiner site (gloves, gowns, or stethoscope) in 33 (67%) of 49 cases . Gloves were contaminated in 63%, gowns in 37%, and stethoscopes in 31% . All three items were positive for VRE in 24% . One case each had stethoscope and gown contamination without glove contamination . Only 1 (2%) of 49 stethoscopes was positive after wiping with an alcohol swab . Contamination at any site was more likely when the patient had a colostomy or ileostomy . Patients identified by rectal-swab culture alone were as likely to contaminate their examiners as were those identified by clinical specimens . CONCLUSIONS: Our study revealed a high rate of examiner contamination with VRE . The similar risk of contamination identified by surveillance and clinical cases reinforces concerns that patients not known to be colonized with VRE could serve as sources for dissemination . Wiping with alcohol is effective in decontaminating stethoscopes.

Chem Biol, 2001 Nov, 8(11), 1095 - 106
Direct interaction of a vancomycin derivative with bacterial enzymes involved in cell wall biosynthesis; Sinha Roy R et al.; BACKGROUND: The glycopeptide antibiotic vancomycin complexes DAla-DAla termini of bacterial cell walls and peptidoglycan precursors and interferes with enzymes involved in murein biosynthesis . Semisynthetic vancomycins incorporating hydrophobic sugar substituents exhibit efficacy against DAla-DLac-containing vancomycin-resistant enterococci, albeit by an undetermined mechanism . Contrasting models that invoke either cooperative dimerization and membrane anchoring or direct inhibition of bacterial transglycosylases have been proposed to explain the bioactivity of these glycopeptides . RESULTS: Affinity chromatography has revealed direct interactions between a semisynthetic hydrophobic vancomycin (DCB-PV), and select Escherichia coli membrane proteins, including at least six enzymes involved in peptidoglycan assembly . The N(4)-vancosamine substituent is critical for protein binding . DCB-PV inhibits transglycosylation in permeabilized E . coli, consistent with the observed binding of the PBP-1B transglycosylase-transpeptidase . CONCLUSIONS: Hydrophobic vancomycins interact directly with a select subset of bacterial membrane proteins, suggesting the existence of discrete protein targets . Transglycosylase inhibition may play a role in the enhanced bioactivity of semisynthetic glycopeptides.

Orthopedics, 2001 Nov, 24(11), 1057 - 60
Hand infections in patients with diabetes mellitus; Connor RW et al.; Fifty diabetic patients with hand infections were studied retrospectively . The cause of infection varied, and the infections were divided into two groups: superficial infections and abscesses . The amputation rate was 14% . Only patients who presented with an abscess required amputation, and of those patients with abscesses, 17.5% required amputation . Eighteen of 38 cultured infections were polymicrobial, 4 contained Enterococcus, 11 contained gram-negative bacteria, and 3 contained anaerobic organisms . Bacteriologic culture analysis initiated a two-drug protocol: ampicillin with sulbactam (Unasyn; Pfizer, New York, NY) or piperacillin with tazobactam (Zosyn; Lederle, Pearl River, NY) and gentamicin (renal adjusted).

J Clin Microbiol, 2001 Dec, 39(12), 4571 - 4
Dissemination of clonally unrelated erythromycin- and glycopeptide-resistant Enterococcus faecium isolates in a tertiary Greek hospital; Maniatis AN et al.; Between September 1999 to February 2001, 25 glycopeptide-resistant Enterococcus faecium (GRE) isolates were recovered from a Greek hospital . The isolates exhibited 13 distinct chromosomal macrorestriction types by pulsed-field gel electrophoresis, and all were erythromycin and vancomycin resistant, carrying the genes vanA and ermB . Vancomycin resistance, always linked with erythromycin resistance, was transferable from 17 isolates . The dissemination of erythromycin-resistant GRE strains may, at least in part, reflect the extensive use of macrolides in husbandry in Greece.

Environ Microbiol, 2001 Oct, 3(10), 658 - 61
Antibiotic resistance in bacteria from magpies (Pica pica) and rabbits (Oryctolagus cuniculus) from west Wales; Livermore DM et al.; The prevalence of antibiotic-resistant bacteria in wild animal and bird populations is largely unknown, with little consistency among the few published reports . We therefore examined intestinal bacteria from magpies (Pica pica) and rabbits (Oryctolagus cuniculus) collected in rural west Wales . Escherichia coli isolates resistant to multiple antibiotics were grown from eight of 20 magpies trapped in spring, 1999 and one of 17 in spring, 2000; the most prevalent resistance trait among these isolates was to tetracycline, but resistances to ampicillin, chloramphenicol, kanamycin, sulphonamide, tetracycline and trimethoprim were also found . Tetracycline-resistant Enterococcus spp . were found in one of 20 magpies in 1999 and three of 17 in 2000 . Only one resistant E . coli isolate was detected among gut bacteria from 13 rabbits, and this strain was resistant only to tetracycline . Differences in the prevalence of resistance between bacteria from rabbits and magpies may reflect differences in diet: rabbits graze field edges, whereas magpies are omnivorous and opportunistic . The resistance genes found in E . coli isolates from magpies mostly corresponded to those common among human isolates, but those conferring tetracycline resistance were unique.

Acta Microbiol Pol, 2001, 50(2), 179 - 82
Influence of iron-restricted conditions on growth and hydroxamate siderophore release in enterococci; Sobis-Glinkowska M et al.; In eleven strains of genus Enterococcus the growth kinetics and hydroxamate siderophore production in iron-deficient medium were investigated . The classical pattern of bacterial growth kinetics and siderophore synthesis was observed.

Chest, 2001 Nov, 120(5), 1744 - 6
Aortic root replacement in a patient with vancomycin-resistant Enterococcus faecium endocarditis and leukemia; Konstantinov IE et al.; Vancomycin-resistant Enterococcus faecium endocarditis is rare and usually occurs in immunocompromised patients . We describe a patient with hairy-cell leukemia and vancomycin-resistant E faecium endocarditis . The patient presented with severe aortic insufficiency . He underwent aortic root replacement with a cryopreserved aortic homograft and was treated with a combination of quinupristin/dalfopristin, ampicillin, and gentamicin.

Clin Lymphoma, 2000 Sep, 1(2), 141 - 5
Enterococcal eschars in cutaneous T-cell lymphoma tumors: a distinct clinical entity; Duvic M et al.; Cutaneous T-cell lymphomas (CTCL) are extranodal non-Hodgkin's T-cell lymphomas that present in the skin, the most common form being mycosis fungoides . The progression of disease is associated with acquired immunodeficiency and increased susceptibility to infections . Ten CTCL patients presented with dark brown to black eschars overlying ulcerated tumors that cultured positive for Enterococcus and healed with appropriate antibiotic therapy . Enterococcal infections in CTCL tumors may be recognized as a distinct clinical entity requiring specific intervention.

Paediatr Drugs, 2001, 3(10), 733 - 61
Commonly used antibacterial and antifungal agents for hospitalised paediatric patients: implications for therapy with an emphasis on clinical pharmacokinetics; Singh J et al.; Due to normal growth and development, hospitalised paediatric patients with infection require unique consideration of immune function and drug disposition . Specifically, antibacterial and antifungal pharmacokinetics are influenced by volume of distribution, drug binding and elimination, which are a reflection of changing extracellular fluid volume, quantity and quality of plasma proteins, and renal and hepatic function . However, there is a paucity of data in paediatric patients addressing these issues and many empiric treatment practices are based on adult data . The penicillins and cephalosporins continue to be a mainstay of therapy because of their broad spectrum of activity, clinical efficacy and favourable tolerability profile . These antibacterials rapidly reach peak serum concentrations and readily diffuse into body tissues . Good penetration into the cerebrospinal fluid (CSF) has made the third-generation cephalosporins the agents of choice for the treatment of bacterial meningitis . These drugs are excreted primarily by the kidney . The carbapenems are broad-spectrum beta-lactam antibacterials which can potentially replace combination regimens . Vancomycin is a glycopeptide antibacterial with gram-positive activity useful for the treatment of resistant infections, or for those patients allergic to penicillins and cephalosporins . Volume of distribution is affected by age, gender, and bodyweight . It diffuses well across serous membranes and inflamed meninges . Vancomycin is excreted by the kidneys and is not removed by dialysis . The aminoglycosides continue to serve a useful role in the treatment of gram-negative, enterococcal and mycobacterial infections . Their volume of distribution approximates extracellular space . These drugs are also excreted renally and are removed by haemodialysis . Passage across the blood-brain barrier is poor, even in the face of meningeal inflammation . Low pH found in abscess conditions impairs function . Toxicity needs to be considered . Macrolide antibacterials are frequently used in the treatment of respiratory infections . Parenteral erythromycin can cause phlebitis, which limits its use . Parenteral azithromycin is better tolerated but paediatric pharmacokinetic data are lacking . Clindamycin is frequently used when anaerobic infections are suspected . Good oral absorption makes it a good choice for step-down therapy in intra-abdominal and skeletal infections . The use of quinolones in paediatrics has been restricted and most information available is in cystic fibrosis patients . High oral bioavailability is also important for step-down therapy . Amphotericin B has been the cornerstone of antifungal treatment in hospitalised patients . Its metabolism is poorly understood . The half-life increases with time and can be as long as 15 days after prolonged therapy . Oral absorption is poor . The azole antifungals are being used increasingly . Fluconazole is well tolerated, with high bioavailability and good penetration into the CSF . Itraconazole has greater activity against aspergillus, blastomycosis, histoplasmosis and sporotrichosis, although it's pharmacological and toxicity profiles are not as favourable.

Neurocirugia (Astur), 2001 Aug, 12(4), 338 - 41
{Intracranial epidural abscess in a newborn secondary to skin catheter}; Fernandez LM et al.; Intracranial epidural abscesses are uncommon lesions, being more frequents in older children and adults . They commonly arise as a result of direct extension of a preexisting infection and rarely present with focal deficit . We present a case of a 11-days old preterm infant who developed an intracranial epidural abscess as a result of an infected scalp vein catheter . The diagnosis was made on the basis of the cranial ultrasound and CT scan images . An identified strain of Enterococcus faecium was cultured from all the samples . The patient underwent a right frontal craniotomy with drainage of the abscess and a 2-week total course of intravenous antibiotics was administrated . CT scan imaging 3 week after the procedure demonstrated no evidence of residual lesion . When present, a scalp vein catheter, in absence of others predisponing factors, must be considered as an etiologic agent for an intracranial epidural abscess in this age-group.

J Med Microbiol, 2001 Nov, 50(11), 1001 - 5
Antibiotic resistance patterns of enterococci isolated from coastal bathing waters; Arvanitidou M et al.; Recreational water should be considered a risk for enterococcal infections in regions with high utilisation and long exposure periods . A total of 1113 enterococcal isolates was obtained from 1670 bathing water samples from 120 bathing areas of seven prefectures in northern Greece . Enterococcus avium, E . raffinosus and E . faecium were the most prevalent species . Single, double and multiple antibiotic resistance patterns were observed in 33.5% 31.0% and 22.8% of the isolates, respectively . Resistance to erythromycin occurred most frequently, in 57.3% isolates, many of which also exhibited resistance to ciprofloxacin and rifampicin as well as high-level resistance to kanamycin and streptomycin . The results suggest that bathing water may contribute to the dissemination of uncommon enterococcal species that exhibit resistance to several antibiotics which are used to treat community-acquired infections.

FEBS Lett, 2001 Nov 2, 507(3), 367 - 70
Tetrathiomolybdate inhibition of the Enterococcus hirae CopB copper ATPase; Bissig KD et al.; Tetrathiomolybdate (TTM) avidly interacts with copper and has recently been employed to reduce excess copper in patients with Wilson disease . We found that TTM inhibits the purified Enterococcus hirae CopB copper ATPase with an IC(50) of 34 nM . Dithiomolybdate and trithiomolybdate, which commonly contaminate TTM, inhibited the copper ATPases with similar potency . Inhibition could be reversed by copper or silver, suggesting inhibition by substrate binding . These findings for the first time allowed an estimate of the high affinity of CopB for copper and silver . TTM is a new tool for the study of copper ATPases.

Pathol Biol (Paris), 2001 Oct, 49(8), 641 - 8
{Risk factors and prevention of the acquisition and transmission of glycopeptide resistant enterococci}; Talon D et al.; We reviewed the literature concerning the role of antibiotic use as a risk factor for glycopeptide-resistant enterococci (VRE) infection/colonisation, to enable us to develop measures for preventing the acquisition and transmission of VRE . We found that the length of stay, the number of stays in hospital and the transfer of patients between hospitals and units were all risk factors for acquiring VRE infection . However, analysis of group and individual data showed that there was also a clear link between vancomycin and third-generation cephalosporin use and the prevalence of VRE colonisation/infection . Evidence for this link was provided by the consistent association and dose-effect relationship observed, and from the frequently consistent variations observed over time . However, it is difficult to give precise recommendations because very few studies have investigated both intrinsic bacterial factors making specific strains more epidemic and the precise characteristics of the conditions determining antibiotic selection pressure . In the absence of this information, and maintaining the prevention measures against cross-contamination which remain a priority, these results suggest that programs aimed at improving the prescription of antibiotics should be initiated in hospitals.

Clin Infect Dis, 2001 Dec 1, 33(11), 1816 - 23 Epub 2001 Oct 19.
Treatment of vancomycin-resistant Enterococcus faecium infections with quinupristin/dalfopristin; Linden PK et al.; Clinicians caring for patients with vancomycin-resistant Enterococcus faecium (VREF) infections face severe constraints in the selection of treatment . Quinupristin/dalfopristin (Synercid) is active in vitro against VREF, with a MIC(90) of 1.0 microg/mL . We investigated the clinical efficacy and safety of this agent in a multicenter, prospective, noncomparative, emergency-use study of 396 patients . Patients were included if they had signs and symptoms of active infection, including bacteremia of unknown origin, intra-abdominal infection, and skin and skin-structure infection, with no alternative antibiotic therapy available . The mean duration of treatment was 20 days (range, 4-40 days) . The clinical response rate was 68.8% in the evaluable subset, and the overall response rate was 65.6% . The most common adverse events related to quinupristin/dalfopristin were arthralgias and myalgias . Related laboratory abnormalities were rare . In this severely ill patient population, quinupristin/dalfopristin was efficacious and demonstrated an acceptable safety profile in the treatment of VREF infection.

N Engl J Med, 2001 Oct 18, 345(16), 1161 - 6
Transient intestinal carriage after ingestion of antibiotic-resistant Enterococcus faecium from chicken and pork; Sorensen TL et al.; BACKGROUND: Antibiotic-resistant enterococci are often present in retail meats, but it is unclear whether the ingestion of these contaminants leads to sustained intestinal carriage . METHODS: We conducted a randomized, double-blind study in 18 healthy volunteers . Six ingested a mixture of 10(7) colony-forming units (CFU) of two glycopeptide-resistant strains of Enterococcus faecium obtained from chicken purchased at a grocery store, six ingested 10(7) CFU of a streptogramin-resistant strain of E . faecium obtained from a pig at slaughter, and six ingested 10(7) CFU of a glycopeptide-susceptible and streptogramin-susceptible strain of E . faecium from chicken purchased at a grocery store . Suspensions of enterococci were prepared in 250 ml of whole milk and were well within the amounts deemed acceptable by Danish food regulations . Stool samples were collected before exposure, daily for 1 week after ingestion, and at 14 and 35 days . Resistant enterococci in stools were identified by selective culture techniques; further molecular characterization of the organisms was also conducted . RESULTS: At the outset, none of the subjects were colonized with glycopeptide-resistant or streptogramin-resistant E . faecium . After ingestion of the study strains, these same strains were isolated from the stools of all subjects, in various concentrations . The test strain was isolated in stool from 8 of 12 subjects on day 6, and from 1 of 12 on day 14 . All stool samples were negative at 35 days . CONCLUSIONS: The ingestion of resistant E . faecium of animal origin leads to detectable concentrations of the resistant strain in stools for up to 14 days after ingestion . The organisms survive gastric passage and multiply.

N Engl J Med, 2001 Oct 18, 345(16), 1155 - 60
Quinupristin-dalfopristin-resistant Enterococcus faecium on chicken and in human stool specimens; McDonald LC et al.; BACKGROUND: The combination of the streptogramins quinupristin and dalfopristin was approved in the United States in late 1999 for the treatment of vancomycin-resistant Enterococcus faecium infections . Since 1974, another streptogramin, virginiamycin, has been used at subtherapeutic concentrations to promote the growth of farm animals, including chickens . METHODS: To determine the frequency of quinupristin-dalfopristin-resistant E . faecium, we used selective medium to culture samples from chickens purchased in supermarkets in Georgia, Maryland, Minnesota, and Oregon and stool samples from outpatients . RESULTS: Between July 1998 and June 1999, samples from 407 chickens from 26 stores in four states were cultured, as were 334 stool samples from outpatients . Quinupristin-dalfopristin-resistant E . faecium was isolated from 237 chicken carcasses and 3 stool specimens . The resistant isolates from stool had low-level resistance (minimal inhibitory concentration {MIC}, 4 microg per milliliter; resistance was defined as a MIC of at least 4 microg per milliliter) . The resistant isolates from chickens in general had higher levels of resistance (MICs ranging from 4 to 32 microg per milliliter; MIC required to inhibit 50 percent of isolates, 8 microg per milliliter) . CONCLUSIONS: Quinupristin-dalfopristin-resistant E . faecium contaminates a large proportion of chickens sold in U.S . supermarkets . However, the low prevalence and low level of resistance of these strains in human stool specimens suggest that the use of virginiamycin in animals has not yet had a substantial influence . Foodborne dissemination of resistance may increase, however, as the clinical use of quinupristin-dalfopristin increases.

Presse Med, 2001 Sep 8, 30(25 Pt 2), VI - IX
{Epidemiological context: microbiological value of Synercid}; Etienne J; MECHANISM OF ACTION: Synercid', an antibiotic designed around the concept of molecular synergism, is composed of 70% dafopristin or spectrogramin A and 30% quinupristin or spectrogramin B . First, dafopristin binds to the ribosomal 50S unit changing the conformation of the ribosome . This increases the affinity of quinupristin that in turn binds to the bacterial ribosome . This double binding interrupts protein synthesis and blocks bacterial growth . ACTIVITY: In vitro, Synercid is particularly active against Gram positive cocci, irrespective of the strain's resistance phenotype . It is notably active against meti-sensitive and meti-resistant S . aureus, S . pneumoniae, S . pyogenes and Enterococcus faecium . MECHANISMS OF RESISTANCE TO MACROLIDES/LINCOSAMIDES/STREPTOGRAMINS: The most frequently encountered mechanism is a modification of the ribosomal target . Two other mechanisms can also be operating: enzyme inactivation or efflux phenomenon . Another mechanism of resistance, LSA phenotype, remains poorly understood . Only a very small proportion of the patients are concerned by resistance (9 patients in a study enrolling 880 patients).

Antimicrob Agents Chemother, 2001 Nov, 45(11), 3223 - 5
Indication of transposition of a mobile DNA element containing the vat(D) and erm(B) genes in Enterococcus faecium; Hammerum AM et al.; The vat(D) and erm(B) genes encoding streptogramin resistance in Enterococcus faecium transferred together, and a direct physical link between erm(B) and vat(D) was detected . Both the vat(D) and erm(B) probes hybridized to fragments of different sizes in the donor and transconjugants, which indicated a transposition event.

Ter Arkh, 2001, 73(8), 63 - 6
{Clinico-laboratory assessment of oframax (cefriaxone) in the treatment of infectious-inflammatory diseases}; Sokolova VI et al.; AIM: To try efficacy and safety of ophramax (cephtriaxon) made in India ("Ranbaxy") in infectious-inflammatory diseases treated in a general hospital . MATERIAL AND METHODS: Ophramax was given in a dose 1 to 4 g/day to 23 patients with pneumonia, chronic bronchitis, soft tissue infection, enterocolitis, etc . Therapeutic effect was examined with bacteriological identification of the infective agents, antibioticograms, agar diffusion test . RESULTS: High sensitivity of pathogens to ophramax was observed in bronchopulmonary diseases (90.7%) . In other infections sensitivity of the pathogens was 59.3% . Enterococci were the only highly resistant pathogens (40.5%) . Ophramax remains in the body in sufficiently high concentrations for 24 hours . This attributes to good therapeutic effect . CONCLUSION: Clinico-microbiological and pharmacokinetic findings show that ophramax can be used as a basic drug for treatment of different infectious-inflammatory diseases . Once-a-day regimen is a great advantage of ophramax.

Clin Infect Dis, 2001 Nov 15, 33(10), 1654 - 60 Epub 2001 Oct 10.
Prolonged colonization with vancomycin-resistant Enterococcus faecium in long-term care patients and the significance of "clearance"; Baden LR et al.; Little is known about the persistence of colonization with vancomycin-resistant Enterococcus faecium (VRE) in the nononcologic, non-intensive care unit patient . We studied all patients who had VRE isolated on > or =2 occasions of > 1 year apart (Study A) and those who had been "cleared" of VRE colonization after 3 negative stool cultures (Study B) . Twelve patients had stored VRE isolates recovered > 1 year apart (Study A), and 58% of paired isolates were genotypically related according to pulsed field gel electrophoresis patterns . In Study B, stool samples were obtained weekly from 21 "cleared" patients for 5 weeks, which revealed that 24% were VRE positive . For these culture-positive patients, 72% of the cultures failed to detect VRE . Recent antibiotic use was significantly more common in the culture-positive patients, as compared with culture-negative patients (P=.003) . Colonization with VRE may persist for years, even if the results of intercurrent surveillance stool and index site cultures are negative . Cultures for detection of VRE in stool samples obtained from patients declared "cleared" are insensitive.

Biochem Biophys Res Commun, 2001 Oct 19, 288(1), 172 - 7
Interaction of the CopZ copper chaperone with the CopA copper ATPase of Enterococcus hirae assessed by surface plasmon resonance; Multhaup G et al.; Intracellular copper routing in Enterococcus hirae can be accomplished by the CopZ metallochaperone . Using surface plasmon resonance analysis, we show here that CopZ interacts with the CopA copper ATPase . The binding affinity of CopZ for CopA was increased in the presence of copper, due to a 15-fold lower dissociation rate constant . Mutating the N-terminal copper binding motif of CopA from CxxC to SxxS abolished this copper-induced effect . Moreover, CopZ failed to show an interaction with an unrelated copper binding protein used as a control . These results show that (i) the CopA copper ATPase specifically interacts with the CopZ chaperone, (ii) this interaction is based on protein-protein interaction, and (iii) surface plasmon resonance is a novel tool for quantitative analysis of metallochaperone-target interactions .

Int J Syst Evol Microbiol, 2001 Sep, 51(Pt 5), 1737 - 43
Enterococcus porcinus sp . nov . and Enterococcus ratti sp . nov., associated with enteric disorders in animals; Teixeira LM et al.; Recent insights have been brought to the taxonomy of the genus Enterococcus by studies applying whole-cell protein analysis and DNA-DNA reassociation experiments, in addition to conventional physiological tests . Using these techniques, a group of 10 strains resembling the physiological group III of enterococcal species was characterized . Five strains were recovered from pigs and five from rats with enteric disorders . On the basis of the results of conventional physiological tests, the most likely identity of these strains was Enterococcus durans or Enterococcus hirae . Analysis of the electrophoretic whole-cell protein profiles showed two distinct clusters of virtually indistinguishable profiles: one composed of strains isolated from pigs, and one composed of strains isolated from rats . These protein profiles were not similar to the profiles of any previously described Enterococcus species . The results of DNA-DNA relatedness experiments were consistent with the results of the protein-profile analysis . The high levels of DNA relatedness found for pig isolates demonstrated that they belong to a new enterococcal species, for which the designation Enterococcus porcinus sp . nov . is proposed (type strain =DS 1390-83T =ATCC 700913T =CCUG 43229T =NCIMB 13634T) . Strains isolated from rats were found to comprise another new species, for which the designation Enterococcus ratti sp . nov . is proposed (type strain =DS 2705-87T =ATCC 700914T =CCUG 43228T =NCIMB 13635T) . This report provides data on the phenotypic and genotypic characterization of these two new enterococcal species, which may represent diarrhoeagenic pathogens for animals.

Clin Infect Dis, 2001 Nov 1, 33(9), 1476 - 82 Epub 2001 Oct 04.
Effective suppression of vancomycin-resistant Enterococcus species in asymptomatic gastrointestinal carriers by a novel glycolipodepsipeptide, ramoplanin; Wong MT et al.; Nosocomial bloodstream infections due to vancomycin-resistant enterococci (VRE) are associated with increased morbidity rates, mortality rates, and hospitalization costs . Gastrointestinal carriage of VRE is an important risk factor for subsequent infections . This 3-arm, phase II, double-blinded, randomized, multicenter, placebo-controlled study evaluated the safety and efficacy of oral ramoplanin (a novel, nonabsorbed glycolipodepsipeptide) versus placebo for suppression of gastrointestinal VRE colonization . Sixty-eight patients who were colonized with VRE were enrolled and received 2 daily doses of ramoplanin (100 mg or 400 mg) or placebo orally for 7 days . The primary end point was the proportion of persons per group from whom VRE were not recovered (VRE-free) on days 7, 14, and 21 after screening . After treatment, VRE-free status was as follows: day 7, none of the 20 patients in the placebo group, and 17 of 21 (P<.001) and 18 of 20 (P<.001) in the 100-mg and 400-mg ramoplanin groups, respectively; on day 14, 2 of 20 patients in the placebo group, and 6 of 21 (P=.134) and 7 of 17 (P=.028), in the 100-mg and 400-mg ramoplanin groups, respectively . By day 21, there were no differences between treatment groups . Adverse events were similar for all treatment groups . Ramoplanin was safe and effective in temporarily suppressing gastrointestinal VRE carriage.

J Biol Chem, 2001 Dec 21, 276(51), 47822 - 7 Epub 2001 Oct 03.
Copper-induced proteolysis of the CopZ copper chaperone of Enterococcus hirae; Lu ZH et al.; The cop operon is a key element of copper homeostasis in Enterococcus hirae . It encodes two copper ATPases, CopA and CopB, the CopY repressor, and the CopZ metallochaperone . It was previously shown that the transcription of the operon is induced by copper . The concomitant increase in the levels of Cop proteins, particularly the CopB copper export ATPase, allows uncompromised growth of E . hirae in up to 5 mm ambient copper . We here show by Western blotting that the steady-state level of CopZ was increased only up to 0.5 mm copper . At higher copper concentrations, the level of CopZ was decreased and became undetectable at 5 mm media copper . When CopZ was overexpressed from a plasmid, the cells exhibited increased sensitivity to copper and oxidative stress, suggesting that high CopZ expression could become toxic to cells . In wild-type cells, the level of mRNA transcripts from the cop operon remained high in up to 5 mm copper, suggesting that CopZ was proteolyzed . Cell extracts were found to contain a copper-activated proteolytic activity that degraded CopZ in vitro . In this assay, Cu-CopZ was more susceptible to degradation than apo-CopZ . The growth of E . hirae in copper increased the copper-inducible proteolytic activity in extracts . Zymographic studies showed the presence of a copper-dependent protease in crude cell lysates . Thus, copper-stimulated proteolysis plays an important role in the regulation of copper homeostasis in E . hirae.

Am J Infect Control, 2001 Oct, 29(5), 316 - 20
Community dissemination of vancomycin-resistant Enterococcus faecium; D'Agata EM et al.; BACKGROUND AND OBJECTIVE: In the United States, vancomycin-resistant enterococci (VRE) are predominantly acquired in the hospital . The extent of dissemination of VRE into the community in the United States has not been examined . Our objective was to determine the prevalence of VRE among nonhospitalized patients . METHODS: We conducted a cross-sectional surveillance study in an ambulatory care clinic . One hundred ambulatory patients participated in the study . Measurements included a written questionnaire on patient demographics, clinical data, and prior exposure to health care settings and antibiotics; rectal swabs; pulsed-field gel electrophoresis; and polymerase chain reaction genotyping . RESULTS: Three of 100 subjects (3%) were colonized with VRE, including one person who did not have any exposure to a health care setting or antibiotics . CONCLUSIONS: VRE was recovered from nonhospitalized patients . Physicians should be alert to the potential of VRE transmission in the ambulatory care setting.

Infect Control Hosp Epidemiol, 2001 Jul, 22(7), 437 - 42
Costs and savings associated with infection control measures that reduced transmission of vancomycin-resistant enterococci in an endemic setting; Montecalvo MA et al.; OBJECTIVE: To determine the costs and savings of a 15-component infection control program that reduced transmission of vancomycin-resistant enterococci (VRE) in an endemic setting . DESIGN: Evaluation of costs and savings, using historical control data . SETTING: Adult oncology unit of a 650-bed hospital . PARTICIPANTS: Patients with leukemia, lymphoma, and solid tumors, excluding bone marrow transplant recipients . METHODS: Costs and savings with estimated ranges were calculated . Excess length of stay (LOS) associated with VRE bloodstream infection (BSI) was determined by matching VRE BSI patients with VRE-negative patients by oncology diagnosis . Differences in LOS between the matched groups were evaluated using a mixed-effect analysis of variance linear-regression model . RESULTS: The cost of enhanced infection control strategies for 1 year was $116,515 . VRE BSI was associated with an increased LOS of 13.7 days . The savings associated with fewer VRE BSI ($123,081), fewer patients with VRE colonization ($2,755), and reductions in antimicrobial use ($179,997) totaled $305,833 . Estimated ranges of costs and savings for enhanced infection control strategies were $97,939 to $148,883 for costs and $271,531 to $421,461 for savings . CONCLUSION: The net savings due to enhanced infection control strategies for 1 year was $189,318 . Estimates suggest that these strategies would be cost-beneficial for hospital units where the number of patients with VRE BSI is at least six to nine patients per year or if the savings from fewer VRE BSI patients in combination with decreased antimicrobial use equalled $100,000 to $150,000 per year.

Mol Microbiol, 2001 Sep, 41(6), 1349 - 56
EmtA, a rRNA methyltransferase conferring high-level evernimicin resistance; Mann PA et al.; Enterococcus faecium strain 9631355 was isolated from animal sources on the basis of its resistance to the growth promotant avilamycin . The strain also exhibited high-level resistance to evernimicin, a drug undergoing evaluation as a therapeutic agent in humans . Ribosomes from strain 9631355 exhibited a dramatic reduction in evernimicin binding, shown by both cell-free translation assays and direct-binding assays . The resistance determinant was cloned from strain 9631355; sequence alignments suggested it was a methyltransferase and therefore it was designated emtA for evernimicin methyltransferase . Evernimicin resistance was transmissible and emtA was localized to a plasmid-borne insertion element . Purified EmtA methylated 50S subunits from an evernimicin-sensitive strain 30-fold more efficiently than those from a resistant strain . Reverse transcription identified a pause site that was unique to the 23S rRNA extracted from resistant ribosomes . The pause corresponded to methylation of residue G2470 (Escherichia coli numbering) . RNA footprinting revealed that G2470 is located within the evernimicin-binding site on the ribosome, thus providing an explanation for the reduced binding of the drug to methylated ribosomes.

Transplantation, 2001 Sep 27, 72(6), 1032 - 7
Epidemiology and clinical consequences of vancomycin-resistant enterococci in liver transplant patients; Bakir M et al.; BACKGROUND: Vancomycin-resistant enterococci (VRE) are increasingly important as pathogens in liver transplant patients . To guide control efforts, we conducted an epidemiological study of the frequency, source, and modes of transmission of VRE at our center . METHODS: During September 1998 through August 1999, we obtained weekly surveillance cultures from consenting liver transplant patients and surfaces in their rooms . Pooled handwash specimens from personnel also were obtained . Specimens were processed on selective media to detect VRE, and isolates were typed by pulsed field gel electrophoresis . Information was collected from patient records concerning in-hospital treatment and clinical course . RESULTS: Serial cultures were obtained during 33 admissions of 29 patients . VRE were detected in initial specimens from 6 admissions, and nosocomial acquisition of VRE occurred in 12 (44%) of the remaining 27 admissions . Seven different strain types of VRE were detected . The initial site of acquisition was stool in all cases; bile became culture-positive in only two patients . Overall, 16 (55%) of the 29 patients became colonized, usually after transplantation . VRE were detected in environmental cultures during 10 admissions and in 2 of 21 pooled handwashes . No statistically significant differences in clinical status or treatment were found when colonized patients were compared to noncolonized controls . The only VRE infection resulted from a choledochojejunostomy anastomotic leak . CONCLUSION: Alimentary tract colonization by VRE occurred commonly in liver transplant patients, probably by cross-transmission . The clinical consequences were modest in the patients studied, but colonized transplant patients provide a substantial reservoir for continued VRE transmission in hospitals.

Kidney Int, 2001 Oct, 60(4), 1511 - 6
Vancomycin-resistant enterococci colonization in patients at seven hemodialysis centers; Tokars JI et al.; BACKGROUND: Vancomycin-resistant enterococci (VRE) are increasing in prevalence at many institutions, and are often reported in dialysis patients . We studied the prevalence of and risk factors for VRE at seven outpatient hemodialysis centers (three in Baltimore, MD, USA, and four in Richmond, VA, USA) . METHODS: Rectal or stool cultures were performed on consenting hemodialysis patients during December 1997 to April 1998 . Consenting patients were recultured during May to July 1998 (median 120 days later) . Clinical and laboratory data and functional status (1 to 10 scale: 1, normal function; 9, home attendant, not totally disabled; 10, disabled, living at home) were recorded . RESULTS: Of 478 cultures performed, 20 (4.2%) were positive for VRE . Among the seven centers, the prevalence of VRE-positive cultures varied from 1.0 to 7.9% . Independently significant risk factors for a VRE-positive culture were a functional score of 9 to 10 (odds ratio 6.9, P < 0.001), antimicrobial receipt within 90 days before culture (odds ratio 6.1, P < 0.001), and a history of injection drug use (odds ratio 5.4, P = 0.004) . CONCLUSIONS: VRE-colonized patients were present at all seven participating centers, suggesting that careful infection-control precautions should be used at all centers to limit transmission . In agreement with previous studies, VRE colonization was more frequent in patients who had received antimicrobial agents recently, underscoring the importance of judicious antimicrobial use in limiting selection for this potential pathogen.

J Clin Microbiol, 2001 Oct, 39(10), 3753 - 6
Comparison and evaluation of antimicrobial susceptibility testing of enterococci performed in accordance with six national committee standardized disk diffusion procedures; Cotter G et al.; Studies were conducted to compare and evaluate antimicrobial susceptibility test results for enterococci obtained by six national committee disk diffusion procedures . Variations in the incidence of isolates in resistance categories and errors were associated with the use of ciprofloxacin, gentamicin, nitrofurantoin, rifampin, and teicoplanin in a number of committee procedures . Results indicate that laboratories performing disk diffusion antimicrobial susceptibility testing may have problems correctly identifying resistance in enterococci with agents used to combat infections and that it may be difficult to compare resistance data for surveillance purposes.

J Microbiol Methods, 2001 Oct, 47(1), 35 - 40
Rapid identification of Enterococcus durans and Enterococcus hirae by PCR with primers targeted to the ddl genes; Knijff E et al.; Species-specific PCR assays with primers targeted to D-alanine:D-alanine ligase (ddl) encoding genes were developed for the identification of Enterococcus durans and E . hirae . The specificity of the primers was validated in a multiplex PCR on well characterised E . durans (n=30) and E . hirae (n=16) strains, all of which were identified correctly . This PCR procedure offers a reliable and rapid alternative to conventional phenotypic methods for speciation of these enterococci of growing clinical importance.

J Microbiol Immunol Infect, 1999 Jun, 32(2), 111 - 5
Antimicrobial susceptibility of clinical isolates of enterococci; Hu BS et al.; To describe antimicrobial resistance patterns of Enterococcus spp., we measured minimal inhibitory concentrations (MICs) of five antimicrobial agents for 174 clinical isolates of enterococci collected in Taichung Veterans General Hospital from November, 1996 to January, 1998 . Major sources included blood (48), the genitourinary tract (39), soft tissue and wounds (28), and the gynecological tract (16) . The sensitivity test of vancomycin was performed using the broth microdilution method . The susceptibility of ampicillin, penicillin, gentamicin, and teicoplanin was tested by the agar dilution method . The MIC90 of penicillin, ampicillin, gentamicin, teicoplanin and vancomycin were 2, 1, > 2,048, 0.125 and 2 microg/mL, respectively . Ampicillin-resistant isolates represented only 4.6% of all enterococci tested . These results reveal that vancomycin-resistant enterococci were found in 1.7% of all enterococci isolates in this study . However, all isolates were sensitive to teicoplanin.

J Biol Chem, 2001 Dec 21, 276(51), 48337 - 40 Epub 2001 Sep 13.
ATP-dependent affinity change of Na+-binding sites of V-ATPase; Murata T et al.; V-type Na(+)-ATPase of Enterococcus hirae binds about six (6 +/- 1) Na(+) ions/enzyme molecule with a high affinity (Murata, T., Igarashi, K., Kakinuma, Y., and Yamato, I . (2000) J . Biol . Chem . 275, 13415-13419) . After the addition of 5 mm ATP, the binding capacity dropped to about 2 (1.8 +/- 0.3) Na(+) ions/enzyme molecule, returning to the initial value concomitant with the decrease of ATP hydrolysis rate . These findings suggest that the affinity of four of six Na(+)-binding sites of the enzyme changes (lowers) in enzyme reaction . The ATP analogs (adenosine 5'-O-(3-thiotriphosphate) or 5'-adenylylimido-diphosphate), ADP, or aluminum fluoride that is postulated to trap ATPases at their transition state did not inhibit the Na(+) binding capacity significantly . Therefore, the affinity decrease of Na(+)-binding sites was unlikely to be due to ATP binding alone or at the transition state of ATP hydrolysis . In the presence of 5 mm ATP, the ATPase showed strong negative cooperativity (n(H) = 0.16 +/- 0.03) for Na(+) stimulation of ATPase activity . The Hill coefficient (n(H)) increased to 1 in parallel to the decrease of ATP concentration in the reaction mixture . Thus, the ATP-dependent affinity change cooperatively occurs in continuous enzyme reaction.

Antimicrob Agents Chemother, 2001 Oct, 45(10), 2931 - 2
Variation within the vat(E) allele of Enterococcus faecium isolates from retail poultry samples; Simjee S et al.; In a survey of retail meat samples, twelve quinupristin-dalfopristin-resistant (MICs, > or =4 mg/liter) Enterococcus faecium isolates that carried a vat(E) gene were recovered . DNA sequence comparison revealed five new variations in the vat(E) allele among 12 isolates, which were designated vat(E-4) through vat(E-8); two isolates had vat(E-1) . There was no correlation between the number of base changes and the quinupristin-dalfopristin MIC.

Antimicrob Agents Chemother, 2001 Oct, 45(10), 2691 - 4
Aminoglycoside resistance genes aph(2")-Ib and aac(6')-Im detected together in strains of both Escherichia coli and Enterococcus faecium; Chow JW et al.; Escherichia coli SCH92111602 expresses an aminoglycoside resistance profile similar to that conferred by the aac(6')-Ie-aph(2")-Ia gene found in gram-positive cocci and was found to contain the aminoglycoside resistance genes aph(2")-Ib and aac(6')-Im (only 44 nucleotides apart) . aph(2")-Ib had been reported previously in Enterococcus faecium SF11770 . aac(6')-Im had not been detected previously in enterococci and was found to be present also 44 nucleotides downstream from aph(2")-Ib in E . faecium SF11770 . aph(2")-Ib and aac(6')-Im are separate open reading frames, each with its own putative ribosome binding site, whereas aac(6')-Ie-aph(2")-Ia appears to be a fusion of two genes with just one start and one stop codon . The deduced AAC(6')-Im protein exhibits 56% identity and 80% similarity to the AAC(6')-Ie domain of the bifunctional enzyme AAC(6')-APH(2") . Our results document the existence of a member of the aph(2") family of genes in gram-negative bacteria and provide evidence suggesting the horizontal transfer of aph(2")-Ib and aac(6')-Im as a unit between gram-positive and gram-negative bacteria.

Appl Microbiol Biotechnol, 2001 Aug, 56(3-4), 378 - 83
Optimization of enterocin P production by batch fermentation of Enterococcus faecium P13 at constant pH; Herranz C et al.; The influence of pH on growth, enterocin P production and glucose consumption by Enterococcus faecium P13 was studied during anaerobic batch fermentation in MRS broth at 32 degrees C in a fermentor . Growth and glucose consumption were maximal at pH 7.0 . Enterocin P production displayed primary metabolite kinetics and was strongly dependent on pH . A maximum antimicrobial activity of 1,949 bacteriocin units (BU) ml(-1) was obtained at pH 6.0, which represented a four-fold increase compared with the antimicrobial activity obtained without pH regulation . The pH exerted a marked effect on the decrease in bacteriocin activity, with the decrease being maximal at pH 7.0 . In this report, we propose models for the growth of E . faecium P13 as well as enterocin P production and inactivation . Enterocin P production decreased when potentially stress-inducing compounds (NaCl or ethanol) were included in the growth medium.

Microbiology, 2001 Sep, 147(Pt 9), 2571 - 8
The VanY(D) DD-carboxypeptidase of Enterococcus faecium BM4339 is a penicillin-binding protein; Reynolds PE et al.; VanD-type Enterococcus faecium BM4339 is constitutively resistant to vancomycin and to low levels of teicoplanin . This strain produces peptidoglycan precursors terminating in D-lactate but, unlike VanA- and VanB-type strains, E . faecium BM4339 has a mutated ddl ligase gene and cannot synthesize D-Ala-D-Ala . Consequently, although it possesses vanX(D) and vanY(D) genes, it should not require an active VanX-type DD-dipeptidase or a VanY-type DD-carboxypeptidase for resistance . The vanY(D) gene contains the signatures of a penicillin-binding protein (PBP) and is believed to encode a penicillin-sensitive DD-carboxypeptidase . The enzyme activity was found to be membrane-bound and inhibited by low concentrations of benzylpenicillin in membrane preparations and in intact bacteria, indicating that the active site was present on the outside surface of the membrane . The 38 kDa protein was revealed as a PBP present in more copies per cell than conventional PBPs and all the protein was accessible to benzylpenicillin added externally, confirming the localization of the active site . A glycopeptide-susceptible strain of E . faecium lacked this PBP, and the membrane-bound DD-carboxypeptidase activity was less than 5% of that of E . faecium BM4339 . Although the active site of VanY(D) was external to the membrane, UDP-MurNAc-tetrapeptide was produced internally, probably from UDP-MurNAc-pentadepsipeptide . The presence of benzylpenicillin at low concentrations in the growth medium substantially reduced the amount of tetrapeptide produced, indicating that inhibition of VanY(D) by benzylpenicillin influenced production of peptidoglycan precursors internally . A model to explain these contrasting observations is proposed.

J Clin Microbiol, 2001 Sep, 39(9), 3379 - 81
Heteroresistance to vancomycin in Enterococcus faecium; Alam MR et al.; This study presents the first report of vancomycin heteroresistance in an Enterococcus faecium isolate from a patient . The original isolate was susceptible in vitro to vancomycin . E-tests showed growth of subcolonies in a zone of inhibition with a vancomycin MIC of >256 microg/ml . Both the susceptible and resistant colonies were from the same strain as determined by PFGE, and both contained the vanA gene as determined by PCR.

Drug Resist Updat, 1999 Aug, 2(4), 224 - 243
Vancomycin-resistant enterococci: recent advances in genetics, epidemiology and therapeutic options; Malathum K et al.; Vancomycin-resistant enterococci (VRE) have gained much attention in the last decade . Currently, there are five known types of vancomycin resistance based on genes encoding ligase enzymes that the organisms use to produce their cell wall precursors, namely, VanA, VanB, VanC, VanD and VanE . An additional unclassified type was discovered in Australia . The basis of resistance among these phenotypes appears to be similar in that the resistant organisms produce peptidoglycan precursors that end in moieties other than D-alanyl-D-alanine, the usual target of vancomycin . The other dipeptide-like termini identified to date include D-alanyl-D-lactate and D-alanyl-D-serine, which have low affinity for glycopeptides . Recent evidence suggests that glycopeptide-producing organisms might be the remote origin of the vancomycin resistance genes . In European countries, avoparcin, a glycopeptide used in farm animals as a growth promoter, has been linked to the occurrence of VRE and occasional common strains have been identified in food products, farm animals, healthy subjects and hospitalized patients . There have been no such reports in the USA where heavy use of vancomycin and use of broad spectrum antibiotics such as cephalosporins have been identified as important risk factors for acquisition of VRE . Transmission within the same or between hospitals has been reported in many countries . Infection control measures and efforts to use antibiotics, particularly vancomycin, more appropriately have been implemented in a number of healthcare facilities with varying degrees of success . Many antibiotics, as a single agent or a combination of drugs, as well as various new antibiotics have been tested in vitro, in animal models, or used in anecdotal cases but clinical data from large comparative trials are not available to date . Because of the limited susceptibility of many VRE to other agents, efforts to control these organisms are particularly important .

Antimicrob Agents Chemother, 2001 Sep, 45(9), 2594 - 7
Role of penicillin-binding protein 5 in expression of ampicillin resistance and peptidoglycan structure in Enterococcus faecium; Sifaoui F et al.; The contribution of penicillin-binding protein 5 (PBP 5) to intrinsic and acquired beta-lactam resistance was investigated by constructing isogenic strains of Enterococcus faecium producing different PBP 5 . The pbp5 genes from three E . faecium clinical isolates (BM4107, D344, and H80721) were cloned into the shuttle vector pAT392 and introduced into E . faecium D344S, a spontaneous derivative of E . faecium D344 highly susceptible to ampicillin due to deletion of pbp5 (MIC, 0.03 microg/ml) . Immunodetection of PBP5 indicated that cloning of the pbp5 genes into pAT392 resulted in moderate overproduction of PBP 5 in comparison to wild-type strains . This difference may be attributed to a difference in gene copy number . Expression of the pbp5 genes from BM4107 (MIC, 2 microg/ml), D344 (MIC, 24 microg/ml), and H80721 (MIC, 512 microg/ml) in D344S conferred relatively low levels of resistance to ampicillin (MICs, 6, 12, and 20 microg/ml, respectively) . A methionine-to-alanine substitution was introduced at position 485 of the BM4107 PBP 5 by site-directed mutagenesis . In contrast to previous hypotheses based on comparison of nonisogenic strains, this substitution resulted in only a 2.5-fold increase in the ampicillin MIC . The reversed-phase high-performance liquid chromatography muropeptide profiles of D344 and D344S were similar, indicating that deletion of pbp5 was not associated with a detectable defect in cell wall synthesis . These results indicate that pbp5 is a nonessential gene responsible for intrinsic resistance to moderate levels of ampicillin and by itself cannot confer high-level resistance.

Folia Microbiol (Praha), 2001, 46(1), 49 - 52
Production of bacteriocins by different enterococcal isolates; Laukova A et al.; Bacteriocins produced by ruminal as well as environmental isolates were found to be heat-stable antimicrobial substances with a broad inhibitory spectrum (including Gram-negative species and sanitary-important species) . The exponential phase of growth and pH 4-7 were optimal for their production . After purification, some of them were sequenced and specified.

Int J Syst Evol Microbiol, 2001 Jul, 51(Pt 4), 1567 - 74
Enterococcus haemoperoxidus sp . nov . and Enterococcus moraviensis sp . nov., isolated from water; Svec P et al.; A polyphasic taxonomic approach was used to study atypical enterococci isolated from surface waters . All strains were characterized by physiological and biochemical tests as well as by genotyping . The results of biochemical tests and tRNA intergenic length polymorphism analysis (tDNA-PCR) divided all studied strains uniformly into two groups . Because these groups were clearly separated from all enterococcal species described to date, 16S rDNA sequence analysis, DNA base composition analysis and DNA-DNA hybridization of representative strains were done to elucidate the taxonomic position of the analysed groups . On the basis of the results obtained, the names Enterococcus haemoperoxidus (type strain CCM 4851T = LMG 19487T) and Enterococcus moraviensis (type strain CCM 4856T = LMG 19486T) are proposed for the two hitherto undescribed species . The type strains and reference cultures have been deposited in the Czech Collection of Microorganisms (CCM), Masaryk University, Brno, Czech Republic, and in the BCCM/LMG Culture Collection, Ghent University, Belgium.

Ann Intern Med, 2001 Aug 7, 135(3), 175 - 83
The effect of vancomycin and third-generation cephalosporins on prevalence of vancomycin-resistant enterococci in 126 U.S . adult intensive care units; Fridkin SK et al.; BACKGROUND: Patient-specific risk factors for acquisition of vancomycin-resistant enterococci (VRE) among hospitalized patients are becoming well defined . However, few studies have reported data on the institutional risk factors, including rates of antimicrobial use, that predict rates of VRE . Identifying modifiable institutional factors can advance quality-improvement efforts to minimize hospital-acquired infections with VRE . OBJECTIVE: To determine the independent importance of any association between antimicrobial use and risk factors for nosocomial infection on rates of VRE in intensive care units (ICUs) . DESIGN: Prospective ecologic study . SETTING: 126 adult ICUs from 60 U.S . hospitals from January 1996 through July 1999 . PATIENTS: All patients admitted to participating ICUs . MEASUREMENTS: Monthly use of antimicrobial agents (defined daily doses per 1000 patient-days), nosocomial infection rates, and susceptibilities of all tested enterococci isolated from clinical cultures . RESULTS: Prevalence of VRE (median, 10%; range, 0% to 59%) varied by type of ICU and by teaching status and size of the hospital . Prevalence of VRE was strongly associated with VRE prevalence among inpatient non-ICU areas and outpatient areas in the hospital, ventilator-days per 1000 patient-days, and rate of parenteral vancomycin use . In a weighted linear regression model controlling for type of ICU and rates of VRE among non-ICU inpatient areas, rates of vancomycin use (P < 0.001) and third-generation cephalosporin use (P = 0.02) were independently associated with VRE prevalence . CONCLUSIONS: Higher rates of vancomycin or third-generation cephalosporin use were associated with increased prevalence of VRE, independent of other ICU characteristics and the endemic VRE prevalence elsewhere in the hospital . Decreasing the use rates of these antimicrobial agents could reduce rates of VRE in ICUs.

Radiat Environ Biophys, 2001 Jun, 40(2), 145 - 51
Photobiological activity of exogenous and endogenous porphyrin derivatives in Escherichia coli and Enterococcus hirae cells; Gabor F et al.; Photodynamic treatment, the combined application of a photosensitiser and visible light, represents a new and promising approach for the inactivation of microorganisms . The photosensitising potentials of exogenous zinc-phthalocyanine-tetrasulphonate (ZnPsTS), tetraphenylporphyrins (TPPs) and endogenous porphyrin derivatives were tested and compared on Gram-negative and Gram-positive bacteria, Escherichia coli B . and Enterococcus hirae, respectively . The synthesis of endogenous porphyrins was induced by 5-aminolevulinic acid (delta-ALA) . The porphyrin- or delta-ALA-treated cells were irradiated with white light . The photosensitising efficiency of endogenous derivatives on both types of bacteria is ZnPcTS < TP(4-OGluOH)3P < TP(4-OGluOH)4P . However, neither exogenous derivatives exhibit appreciable photosensitising activity for disinfection application . ALA-induced photodynamic treatment showed good potential for the inactivation of Escherichia coli cells, but not towards Enterococcus hirae cells . The failure of photosensitisation of the Enterococcus hirae strain selected indicates that apart from the Gram-positive character, other structural elements of the membrane can influence the result of photodynamic treatments.

J Antibiot (Tokyo), 2001 May, 54(5), 455 - 9
Synthesis of hydrophobic N'-mono and N',N"-double alkylated eremomycins inhibiting the transglycosylation stage of bacterial cell wall biosynthesis; Pavlov AY et al.; A series of hydrophobic N'-mono and N',N"-double alkylated derivatives of the glycopeptide antibiotic eremomycin were synthesized by reductive alkylation after preliminary protection of the N-terminal amino group of the peptide backbone . The investigation of the antibacterial activity in vitro showed that N'-C10H21- and N'-p-(p-chlorophenyl)benzyl derivatives of eremomycin are the most active against vancomycin-resistant enterococci among the compounds obtained though they are less effective than the corresponding lipophilic derivatives of vancomycin . The introduction of two hydrophobic substituents led to a decrease in activity against both susceptible and resistant bacteria . The biochemical evaluation of the mode of action revealed that in addition to binding to D-Ala-D-Ala these compounds also have an alternative mechanism of action that does not require substrate binding.

J Med Microbiol, 2001 Aug, 50(8), 682 - 7
Characterisation of VanA and VanB elements from glycopeptide-resistant Enterococcus faecium from Greece; Demertzi E et al.; Ten glycopeptide-resistant Enterococcus faecium isolates from separate patients in Laikon General Hospital, Athens were studied . Eight isolates had the VanA phenotype and represented variants of three strains based on SmaI macrorestriction banding patterns . Their VanA elements were compared with the prototype element, Tn1546, by an overlapping PCR method . Three related isolates contained resistance elements indistinguishable from Tn1546 (designated Greek type I) . The other five isolates all contained identical elements that differed from Tn1546 by the presence of IS1251 between vanS and vanH, by a point mutation (G --> T) at nucleotide position 8234 within vanX and by a partial loss of transposition gene orf1 (designated Greek type II) . Two distinct strains of E . faecium with the VanB phenotype were obtained . HhaI digestion of an amplified fragment of the vanB gene indicated that both strains contained the vanB2 allele, and further PCR assays confirmed that the vanB2 gene cluster was located within a Tn5382-like element.

J Exp Zool, 2001 Jul 1, 290(2), 125 - 35
Mannan-degrading enzymes purified from the crop of the brown garden snail Helix aspersa Müller (Gastropoda Pulmonata); Charrier M et al.; Two mannan-degrading enzymes were purified from the crop of the terrestrial snail Helix aspersa Muller . The crude extracts were taken from dormant (for 4 months) snails . The enzymes were a betaD-mannanase of 37.4 +/- 0.3 kDa (EC 3.2.1.78) and a betaD-mannosidase of 77.8 +/- 1.9 kDa (EC 3.2.1.25) . Both enzymes degraded insoluble mannan, releasing either mannose only (beta-mannosidase) or oligosaccharides, possibly mannotriose and mannopentaose (beta-mannanase) . The beta-mannanase had a typical endo-activity pattern, while the beta-mannosidase was an exoenzyme . The incubation of both enzymes with mannan increased the catalysis by 83% . The best synergy was found with 75% mannosidase combined with 25% mannanase . The beta-mannanase also hydrolysed beta-linked heteromannans and its affinity for different galactomannans was studied . The Km values, varying from 2.89 +/- 0.47 mg x ml(-1) to 0.26 +/- 0.01 mg x ml(-1), revealed the inhibitory effect of the alphaD-galactosyl residues released . The beta-mannosidase was acidic (optimum pH = 3.3) and heat-sensitive (50% residual activity at 42 degrees C after 5 min of pre-incubation), while the beta-mannanase remained stable until 48.5 degrees C (50% residual activity) and over a pH range of 4.3-7.5 . The properties of these mannanolytic enzymes are discussed in this paper compared with those purified in other gastropods and in a bacterium, Enterococcus casseliflavus, a quite similar strain previously isolated from this snail intestine . The occurrence of thermostable enzymes in H . aspersa digestive tract could be a zootechnic parameter of great importance for snail farming . J . Exp . Zool . 290:125-135, 2001 .

Structure (Camb), 2001 Jul 3, 9(7), 547 - 57
Structure of the UDP-glucosyltransferase GtfB that modifies the heptapeptide aglycone in the biosynthesis of vancomycin group antibiotics; Mulichak AM et al.; BACKGROUND: Members of the vancomycin group of glycopeptide antibiotics have an oxidatively crosslinked heptapeptide scaffold decorated at the hydroxyl groups of 4-OH-Phegly4 or beta-OH-Tyr6 with mono- (residue 6) or disaccharides (residue 4) . The disaccharide in vancomycin itself is L-vancosamine-1,2-glucose, and in chloroeremomycin it is L-4-epi-vancosamine-1,2-glucose . The sugars and their substituents play an important role in efficacy, particularly against vancomycin-resistant pathogenic enterococci . RESULTS: The glucosyltransferase, GtfB, that transfers the glucose residue from UDP-glucose to the 4-OH-Phegly4 residue of the vancomycin aglycone, initiating the glycosylation pathway in chloroeremomycin maturation, has been crystallized, and its structure has been determined by X-ray analysis at 1.8 A resolution . The enzyme has a two-domain structure, with a deep interdomain cleft identified as the likely site of UDP-glucose binding . A hydrophobic patch on the surface of the N-terminal domain is proposed to be the binding site of the aglycone substrate . Mutagenesis has revealed Asp332 as the best candidate for the general base in the glucosyltransfer reaction . CONCLUSIONS: The structure of GtfB places it in a growing group of glycosyltransferases, including Escherichia coli MurG and a beta-glucosyltransferase from T4 phage, which together form a subclass of the glycosyltransferase superfamily and give insights into the recognition of the NDP-sugar and aglycone cosubstrates . A single major interdomain linker between the N- and C- terminal domains suggests that reprogramming of sugar transfer or aglycone recognition in the antibiotic glycosyltransferases, including the glycopeptide and also the macrolide antibiotics, will be facilitated by this structural information.

Clin Infect Dis, 2001 Aug 15, 33(4), 511 - 6 Epub 2001 Jul 11.
Clinical and molecular characterization of vancomycin-resistant Enterococcus faecium strains during establishment of endemicity; D'Agata EM et al.; To characterize the molecular epidemiology of vancomycin-resistant Enterococcus faecium (VREF) in Tennessee, VREF isolates that were recovered from patients during a 3-year period at a tertiary care center and throughout the state were typed by means of pulsed-field gel electrophoresis . Clinical characteristics and outcomes of patients colonized or infected with different strain types were also examined . A total of 34 different strain types were identified . A single VREF strain (type O) predominated (63 {61%} of 103 single-patient isolates (i.e., 1 isolate per patient) obtained from 7 different health care institutions) . There were no significant differences between patients harboring type O strains and those harboring non-type O strains (P> or =.05) . The rate of recovery of type O subtypes and strains other than type O increased over the 3-year study period . Establishment of VREF endemicity was initially characterized by clonal spread of type O strains . Subsequently, polyclonal dissemination may have been due to microevolutionary changes among type O strains.

Clin Infect Dis, 2001 Aug 15, 33(4), 477 - 82 Epub 2001 Jul 11.
Vancomycin-resistant Enterococcus faecium meningitis successfully managed with linezolid: case report and review of the literature; Zeana C et al.; Enterococci cause serious illness in immunocompromised patients and severely ill, hospitalized patients . Resistance to vancomycin has increased in frequency during the past few years . Limited therapeutic options are available for vancomycin-resistant enterococcal infections and the optimum therapy has not been established . We report a case of nosocomial vancomycin-resistant Enterococcus faecium meningitis in the setting of hyperinfection with Strongyloides stercoralis that was successfully treated with linezolid . We also review the previously reported cases of vancomycin-resistant E . faecium meningitis.

Clin Infect Dis, 2001 Aug 15, 33(4), 473 - 6 Epub 2001 Jul 06.
Evaluation of zinc bacitracin capsules versus placebo for enteric eradication of vancomycin-resistant Enterococcus faecium; Mondy KE et al.; Patients who are colonized with enteric vancomycin-resistant Enterococcus faecium (VREF) are a major reservoir for transmission of and infection with this organism . In a randomized, controlled study to assess the effectiveness of high-dose bacitracin in the eradication of enteric VREF, 12 patients who were colonized with VREF were randomized to receive placebo (n=6) or orally administered zinc bacitracin (n=6) for 10 days . Posttreatment perirectal or stool cultures indicated that after 3 weeks, VREF had been eradicated from the stool of only 2 (33%) of 6 patients in each group . Of the 8 remaining patients who were still VREF-positive at 3 weeks after treatment, 5 (62%) had later evidence of spontaneous enteric eradication at 8 weeks . Further testing of VREF isolates revealed that a significant number (n=22, 76%) were resistant to bacitracin and that patients may have been colonized with multiple different VREF strains . Although bacitracin was not effective in the enteric eradication of VREF, the high rates of spontaneous eradication suggest that other host and environmental factors are more important in achieving long-term suppression or elimination of VREF colonization.

Clin Infect Dis, 2001 Aug 15, 33(4), 445 - 52 Epub 2001 Jul 11.
Cost of hospitalization for and risk factors associated with vancomycin-resistant Enterococcus faecium infection and colonization; Webb M et al.; The increase in costs of hospitalization for patients with drug-resistant infection may be associated with drug resistance itself or with the severity of the underlying illness that predisposes patients to acquire the drug-resistant infection . To address this issue, risk factors and cost of hospitalization were compared for patients infected or colonized with vancomycin-susceptible Enterococcus faecium (VSEF) or vancomycin-resistant E . faecium (VREF) in a large tertiary-care hospital in New York City . From January 1995 through December 1996, 157 patients with VSEF and 262 patients with VREF were identified . CMI (case-mix index) was assigned to each patient as a measure of severity of illness, with a CMI of 1 considered to represent illness of average severity . For all patients who were assigned a CMI of <3, the cost per day of hospitalization for patients with VREF was significantly greater than that for patients with VSEF . However, for patients with a CMI of >3, there was no difference between cost of hospitalization for patients with VREF and that for patients with VSEF . These observations indicate that, although vancomycin resistance is associated with an increased cost of hospitalization for less severely ill patients with VREF, patients with severe underlying illness, regardless of vancomycin resistance, incur similar hospitalization costs.

Eur J Clin Microbiol Infect Dis, 2001 May, 20(5), 309 - 14
Recovery from a single blood culture of two enterococcus gallinarum isolates carrying both vanC-1 and vanA cluster genes and differing in glycopeptide susceptibility; Biavasco F et al.; Two Enterococcus gallinarum isolates distinguished by different colony sizes were recovered from the same blood culture from a woman with acute myeloid leukemia . They were designated E31 (the one with larger colonies) and E32 (the one with smaller colonies) . Both isolates were glycopeptide resistant, but the MICs of vancomycin and teicoplanin for E31 (32 and 2 microg/ml, respectively, consistent with the VanC phenotype) and E32 (128 and 16 microg/ml, respectively, consistent with the VanA phenotype) were different . E31 and E32 had the same plasmid profile and showed identical pulsed-field gel electrophoresis patterns after digestion of total DNA with NotI and a two-band variation after digestion with SmaI . Polymerase chain reaction experiments showed that both isolates had both the vanC-1 and vanA genes and carried a Tn1546-related transposon lacking orf1, vanY, and vanZ . The absence of these three genes was confirmed by Southern analysis with appropriate probes . Southern hybridization experiments using a vanA probe showed that this atypical Tn1546-related element appeared to be located on the chromosome . In both E31 and E32, the vanA probe hybridized to EcoRV and HindIII fragments larger in size than the hybridizing fragments observed in the VanA prototype strain Enterococcus faecium BM4147, suggesting the lack of the relevant EcoRV and HindIII restriction sites.

Lett Appl Microbiol, 2001 Jul, 33(1), 65 - 70
Differentiation of Enterococcus spp . by cell membrane fatty acid methyl ester profiling, biotyping and ribotyping; Lang MM et al.; AIMS: Gas chromatographic analysis of cell membrane fatty acid methyl esters (FAME), biochemical profiling (biotyping) and EcoRI restriction endonuclease profiling of DNA containing ribosomal RNA sequences (ribotyping) were compared for differentiation of Enterococcus spp . METHODS AND RESULTS: FAME profiling, biotype profiling and ribotyping of 41 strains from retail Swiss-type cheeses and five strains from culture collections resulted in 17, 25 and 26 groups, respectively, with only two pairs of strains having the same FAME group, biotype profile and ribogroup . CONCLUSION: Substantial overlap occurred in groupings assigned by the three methods . SIGNIFICANCE AND IMPACT OF THE STUDY: Differentiation of Enterococcus spp . strains increases if multiple methods are used.

Scand J Infect Dis, 2001, 33(5), 375 - 9
Successful treatment of vancomycin-resistant Enterococcus faecium meningitis with linezolid: case report and literature review; Shaikh ZH et al.; Vancomycin-resistant enterococci (VRE) are a rare cause of meningitis, occurring primarily in patients who have undergone neurosurgical procedures . We describe the first reported case of VRE meningitis successfully treated with linezolid . A 56-y-old female with subarachnoid hemorrhage underwent ventriculostomy and embolization of cerebral aneurysms . Her postoperative course was complicated by multiple infections needing repeated antibiotic courses, culminating in the development of VRE meningitis . She was treated with 600 mg of i.v . linezolid (MIC < 0.75 microg/ml) every 12 h for 6 weeks . After the fourth dose, peak and trough linezolid concentrations were 11.45 and 0.14 microg/ml in serum and 3.19 and 2.39 microg/ml in cerebral spinal fluid (CSF) . On Day 19 of linezolid therapy, serum and CSF trough concentrations were 1.53 and 2.98 microg/ml, respectively . Linezolid achieved sufficient CSF concentrations to bring about clinical and bacteriological cure . We conclude that i.v . linezolid may be a useful option for treating VRE meningitis . We also present findings of a literature review, which identified 11 cases of VRE meningitis treated with other pharmacologic agents with mixed success.

Endoscopy, 2001 Jun, 33(6), 523 - 8
Freely accessible endoscope channels improve efficacy of cleaning; Dietze B et al.; BACKGROUND AND STUDY AIMS: Inadequate cleaning and disinfection of medical devices, including flexible endoscopes, can result in the transmission of micro-organisms to patients . The aim of this study was to investigate the influence of the design of medical devices on the efficacy of manual cleaning of endoscope channels . MATERIALS AND METHODS: The investigation was carried out using four endoscopes (two duodenoscopes and two gastroscopes) . The air/water channels of one duodenoscope and one gastroscope were freely accessible and could be brushed . The instrumentation and the air/water channels were contaminated with blood containing Enterococcus faecium as a test organism . After manual cleaning of the channels by flushing and, where possible, brushing, the recovery rates for the test organism were studied . RESULTS: The comparable rates for recovery of the test organism after cleaning of the instrumentation channels proved that the method used was reproducible . With regard to the air/water channels, the rate of micro-organisms in the cleaning solution recovered after flushing alone was a maximum of 3 % relative to the rate detected after brushing and flushing . CONCLUSIONS: The data collected in the study show that only flushing channels that are not freely accessible resulted in significantly lower (P<0.001) recovery rates for the test organism . In practice, this means that contamination may remain in the channels, and it shows that the design of a medical device has an important influence on the reprocessing of reusable instruments such as flexible endoscopes.

Vet Res, 2001 May-Aug, 32(3-4), 227 - 41
Resistance to antibiotics in the normal flora of animals; Sorum H et al.; The normal bacterial flora contains antibiotic resistance genes to various degrees, even in individuals with no history of exposure to commercially prepared antibiotics . Several factors seem to increase the number of antibiotic-resistant bacteria in feces . One important factor is the exposure of the intestinal flora to antibacterial drugs . Antibiotics used as feed additives seem to play an important role in the development of antibiotic resistance in normal flora bacteria . The use of avoparcin as a feed additive has demonstrated that an antibiotic considered "safe" is responsible for increased levels of antibiotic resistance in the normal flora enterococci of animals fed with avoparcin and possibly in humans consuming products from these animals . However, other factors like stress from temperature, crowding, and management also seem to contribute to the occurrence of antibiotic resistance in normal flora bacteria . The normal flora of animals has been studied with respect to the development of antibiotic resistance over four decades, but there are few studies with the intestinal flora as the main focus . The results of earlier studies are valuable when focused against the recent understanding of mobile genetics responsible for bacterial antibiotic resistance . New studies should be undertaken to assess whether the development of antibiotic resistance in the normal flora is directly linked to the dramatic increase in antibiotic resistance of bacterial pathogens . Bacteria of the normal flora, often disregarded scientifically, should be studied with the intention of using them as active protection against infectious diseases and thereby contributing to the overall reduction of use of antibioties in both animals and humans.

Infect Control Hosp Epidemiol, 2001 May, 22(5), 301 - 3
Outbreak of vancomycin-resistant Enterococcus faecium in a neonatal intensive care unit; Rupp ME et al.; An outbreak of vancomycin-resistant Enterococcus faecium involving 28 infants in a neonatal intensive care unit was observed . Successful control of the outbreak was achieved following use of patient and staff cohorting, contact isolation precautions, patient and environmental surveillance cultures, environmental decontamination, molecular typing, introduction of an alcohol-based hand disinfectant, and decreased use of vancomycin.

Clin Infect Dis, 2001 Jul 15, 33(2), 210 - 9 Epub 2001 Jun 14.
Vancomycin-resistant enterococci: mechanisms and clinical observations; Gold HS; Enterococci are not generally regarded as highly virulent bacterial pathogens . However, resistance to many antimicrobial drugs complicates treatment of enterococcal infections . Acquired resistance to high concentrations of glycopeptide antibiotics, specifically vancomycin, has exacerbated this problem . This article seeks to concisely review the mechanisms of that resistance and its effects on clinical management of enterococcal infections, as well as clinical microbiology and infection control.

Clin Infect Dis, 2001 Jul 15, 33(2), 151 - 7 Epub 2001 Jun 15.
Acquisition of vancomycin-resistant enterococci during scheduled antimicrobial rotation in an intensive care unit; Puzniak LA et al.; Scheduled rotation of treatment of gram-negative antimicrobial agents has been associated with reduction of serious gram-negative infections . The impact of this practice on other nosocomial infections has not been assessed . The purpose of this study was to determine if scheduled antimicrobial rotation reduced rates of acquisition of enteric vancomycin-resistant enterococci (VRE) among 740 patients admitted to an intensive care unit (ICU) . The preferred gram-negative agent was ceftazidime during rotation 1 and ciprofloxacin during rotation 2 . Unadjusted VRE acquisition rates were 8.5 cases per 1000 ICU days and 11.7 cases per 1000 ICU days during rotations 1 and 2, respectively (P<.01) . However, scheduled antimicrobial rotation of ceftazidime with ciprofloxacin had no effect on the risk of acquiring VRE in the ICU after adjustment for known risk factors . Independent predictors of acquisition of VRE were enteral feedings, higher colonization pressure, and increased duration of anaerobic therapy . Our findings can confirm no additional beneficial or adverse effect on VRE acquisition among ICU patients as a result of this practice.

J Antimicrob Chemother, 2001 Jul, 48(1), 131 - 5
In vitro and in vivo efficacy of a novel fluoro-ketolide HMR 3562 against enterococci; Guitton M et al.; The in vitro activity of HMR 3562, a new 2-fluoro-ketolide drug, was investigated against 95 enterococci, including 36 vancomycin-resistant strains . HMR 3562 inhibited 90% of enterococci susceptible or resistant to erythromycin A at 0.005 and 0.6 mg/L, respectively . HMR 3562 was highly active in murine peritonitis induced by five enterococci, irrespective of resistance phenotype, displaying effective doses in the range 3.4-21.8 mg/kg . The results demonstrate the potential of HMR 3562 in the treatment of infections caused by multiresistant enterococci.

Biochem J, 2001 Jul 1, 357(Pt 1), 217 - 23
Structure-function analysis of purified Enterococcus hirae CopB copper ATPase: effect of Menkes/Wilson disease mutation homologues; Bissig KD et al.; The Enterococcus hirae CopB ATPase (EC 3.6.1.3) confers copper resistance to the organism by expelling excess copper . Two related human ATPase genes, ATP7A (EC 3.6.1.36) and ATP7B (EC 3.6.1.36), have been cloned as the loci of mutations causing Menkes and Wilson diseases, diseases of copper metabolism . Many mutations in these genes have been identified in patients . Since it has not yet been possible to purify the human copper ATPases, it has proved difficult to test the impact of mutations on ATPase function . Some mutations occur in highly conserved sequence motifs, suggesting that their effect on function can be tested with a homologous enzyme . Here, we used the E . hirae CopB ATPase to investigate the impact of such mutations on enzyme function in vivo and in vitro . The Menkes disease mutation of Cys-1000-->Arg, changing the conserved Cys-Pro-Cys ('CPC') motif, was mimicked in CopB . The corresponding Cys-396-->Ser CopB ATPase was unable to restore copper resistance in a CopB knock-out mutant in vivo . The purified mutant ATPase still formed an acylphosphate intermediate, but possessed no detectable ATP hydrolytic activity . The most frequent Wilson disease mutation, His-1069-->Gln, was introduced into CopB as His-480-->Gln (H480Q) . This mutant CopB also failed to confer copper resistance to a CopB knock-out strain . Purified H480Q CopB formed an acylphosphate intermediate and retained a small, but significant, ATPase activity . Our results reveal that Cys-396 and His-480 of CopB are key residues for ATPase function, and similar roles are suggested for Cys-1000 and His-1069 of Menkes and Wilson ATPases respectively.

Pharmacotherapy, 2001 Jun, 21(6), 661 - 8
Hyperbilirubinemia during quinupristin-dalfopristin therapy in liver transplant recipients: correlation with available liver biopsy results; Linden PK et al.; STUDY OBJECTIVE: To review the liver histopathology in transplant recipients who developed hyperbilirubinemia during therapy with quinupristin-dalfopristin, a new streptogramin antibiotic, and to ascertain whether objective histologic evidence of adverse drug effect could be correlated to serum bilirubin levels . DESIGN: Retrospective analysis . SETTING: University of Pittsburgh Medical Center . PATIENTS: From a database of 34 liver recipients who received quinupristin-dalfopristin for vancomycin-resistant Enterococcus faecium infection who were prospectively enrolled in a multicenter, open-label, emergency-use protocol, the data for a subset of 25 patients who underwent one or more liver biopsies during therapy were reviewed for this study . INTERVENTIONS: Quinupristin-dalfopristin was administered intravenously at 7.5 mg/kg every 8 hours . Available serum bilirubin levels from before, during, and 1 week after therapy were tabulated . Liver biopsy results obtained within 1 week before and during therapy were retrospectively reviewed . Histopathologic results were characterized and correlated to bilirubin level . MEASUREMENTS AND MAIN RESULTS: Cholestatic changes were already present in 15 of 17 patients who underwent biopsy before therapy . During therapy, the most common findings from 40 biopsies (25 patients) were cholestasis (33 biopsies), acute rejection (10), and periportal inflammation (8) . There was no evidence of drug-specific histopathologic injury . CONCLUSION: Hyperbilirubinemia in these patients was likely multifactorial and most frequently due to sepsis and prior graft injury.

Am J Forensic Med Pathol, 2001 Jun, 22(2), 207 - 10
Unexpected childhood death due to a rare complication of ventriculoperitoneal shunting; Byard RW et al.; A 10-year-old boy with Arnold-Chiari malformation, spina bifida, and a ventriculoperitoneal shunt for hydrocephalus died unexpectedly, having appeared to be only mildly unwell with fever on the night before death . At autopsy, the shunt was partially obstructed with an associated enterococcal meningitis . The tip of the shunt was located within the transverse colon, which was embedded in a mass of fibrous adhesions resulting from previous abdominal surgery . Blood cultures were sterile . Intestinal perforation is a rare complication of ventriculoperitoneal shunting that may be associated with the development of meningitis and unexpected death . The autopsy assessment of children with such indwelling devices requires examination of the functional state of the shunt, full septic workup, and determination of the precise location of the tip of the catheter within the peritoneal cavity.

Clin Infect Dis, 2001 Jul 1, 33 Suppl 1, S22 - 5
Posttransplant microbiological surveillance; Snydman DR; Posttransplant microbiological surveillance should be used when the likelihood of infection in a transplant recipient is high and the sensitivity and specificity of the test can provide a high positive or negative predictive value . Testing is also performed in some instances to monitor the patient's response to therapy . Examples of successful posttransplant microbiological surveillance include molecular detection of cytomegalovirus and Epstein-Barr virus and virus load determinations, as well as hepatitis B and C detection and virus load testing . Routine fungal and bacterial surveillance are generally not necessary, except for Candida colonization detection or vancomycin-resistant enterococcal detection in high-risk subgroups . The organ transplanted may also play a role in the type of routine surveillance recommended.

Antonie Van Leeuwenhoek, 2000 Dec, 78(3-4), 379 - 84
Teicoplanin biosynthesis genes in Actinoplanes teichomyceticus; Sosio M et al.; The genetic determinants for the biosynthesis of the glycopeptide antibiotic teicoplanin were identified . In order to isolate the corresponding gene cluster, oligonucleotides derived from highly conserved motifs in peptide synthetases were used . These synthetic probes, and gene fragments derived from the balhimycin gene cluster of Amycolatopsis mediterranei, led to the identification of the likely teicoplanin gene cluster centered on a region of ca . 110 kb from the genome of Actinoplanes teichomyceticus, the teicoplanin producer . Partial nucleotide sequences identified partial ORFs likely to encode two glycosyltransferases, three P-450 monooxygenases and one ABC transporter . The corresponding genes have been found in other glycopeptide gene clusters . Furthermore, upstream to the peptide synthetase region a segment was identified with a remarkable similarity to the vanHAX operon, conferring resistance to glycopeptides in enterococci . Thus, in contrast to the other glycopeptide producers thus far analyzed, in A . teichomyceticus the genes for teicoplanin biosynthesis are closely linked to homologs of glycopeptide resistance commonly found in vancomycin-resistant enterococci.

Infect Control Hosp Epidemiol, 2001 Apr, 22(4), 248 - 57
A review of single-use and reusable gowns and drapes in health care; Rutala WA et al.; Gowns and drapes are used widely in healthcare facilities . Gowns have been used to minimize the risk of disease acquisition by healthcare providers, to reduce the risk of patient-to-patient transmission, and during invasive procedures to aid in maintaining a sterile field . Drapes have been used during invasive procedures to maintain the sterility of environmental surfaces, equipment, and patients . This article reviews the use of gowns and drapes in healthcare facilities, including the characteristics, costs, benefits, and barrier effectiveness of single-use and reusable products . Currently, gowns protect healthcare personnel performing invasive procedures from contact with bloodborne pathogens . Although gowns have been recommended to prevent patient-to-patient transmission in certain settings (eg, neonatal intensive care unit) and for certain patients (eg, those infected with vancomycin-resistant enterococci), scientific studies have produced mixed results of their efficacy . While appropriate use of drapes during invasive procedures is recommended widely as an aid in minimizing contamination of the operative field, the efficacy of this practice in reducing surgical-site infections has not been assessed by scientific studies . Based on an evaluation of the functional requirements, environmental impact, and economics of gowns and drapes, clear superiority of either reusable or single-use gowns and drapes cannot be demonstrated . The selection of particular gowns and drapes by individual healthcare facilities requires an assessment of the facility's requirements, available products, and costs and should be based on the desired characteristics of an ideal gown or drape as defined in this paper.

Infect Control Hosp Epidemiol, 2001 Apr, 22(4), 217 - 9
Management of an outbreak of vancomycin-resistant enterococci in the medical intensive care unit of a cancer center; Hanna H et al.; Between November 1996 and February 1997, 17 episodes of vancomycin-resistant enterococci (VRE) infection or colonization (9 infections, 8 colonizations), all with the same or a similar genomic DNA pattern, were identified in the medical intensive care unit (MICU) of a tertiary-care cancer hospital . The cases were genotypically traced to a patient who was admitted to the hospital in September 1996 and who, by December 1996, had four different admissions to the MICU . Multifaceted infection control measures, including decontamination of the environment and of nondisposable equipment, halted the nosocomial transmission of VRE in the MICU.

J Clin Microbiol, 2001 Jun, 39(6), 2298 - 9
High-frequency recovery of quinupristin-dalfopristin-resistant Enterococcus faecium isolates from the poultry production environment; Hayes JR et al.; The occurrence of resistance to the streptogramin quinupristin-dalfopristin in Enterococcus faecium isolates from chickens on the Eastern Seaboard, was evaluated . Quinupristin-dalfopristin resistance was found in 51 to 78% of E . faecium isolates from the food production environment . The high level of resistance in this organism suggests that this reservoir of resistance may compromise the therapeutic potential of quinupristin-dalfopristin.

J Clin Microbiol, 2001 Jun, 39(6), 2140 - 5
High prevalence of VanB2 vancomycin-resistant Enterococcus faecium in Taiwan; Lu JJ et al.; Thirty-six VanB glycopeptide-resistant Enterococcus faecium isolates were collected from patients in five different hospitals in Taiwan . The vancomycin resistance genes were amplified by the long vanB PCR, which amplifies the 6,373-bp vanB gene cluster including the vanR(B2), vanS(B2), vanY(B2), vanW(B2), vanH(B2), vanB2, and vanX(B2) genes . The deduced amino acid sequences were found to be 95 to 98% homologous to those of the vanB1 gene cluster: VanR(B1), 97%; VanS(B1), 97%; VanY(B1), 96%; VanH(B1), 95%; VanB1, 96%; and VanX(B1), 98% . Restriction enzyme analysis of the long vanB PCR products revealed that all 36 isolates had the same vanB2-specific pattern . DNA sequence analysis of the vanB2 gene, which is a D-Ala-D-Lac ligase gene, revealed that none of the 36 sequences were identical to the previously published vanB2 sequence . Thirty-one isolates had 1 nucleotide different from the published vanB2 sequence . The sequences of the other five isolates differed from the published vanB2 sequence by 2 or 3 nucleotides . Four isolates with a low or moderate resistance to vancomycin (MIC = 4 to 32 microg/ml) were found to have the same leucine-to-methionine change at amino acid position 308 of the vanB2 gene . The genomic DNAs of all 36 isolates were digested with SmaI and then typed by pulsed-field gel electrophoresis (PFGE) . Eight different PFGE types (I to VIII) were observed, and type I was found to be prevalent in all hospitals examined in this study . This result suggests that intra- and interhospital dissemination of this E . faecium strain has occurred in Taiwan.

J Antibiot (Tokyo), 2001 Mar, 54(3), 239 - 49
Collinone, a new recombinant angular polyketide antibiotic made by an engineered Streptomyces strain; Martin R et al.; Large chromosomal DNA fragments containing different parts of the putative rubromycin polyketide synthase gene cluster were cloned and functionally expressed in S . coelicolor CH999 . Expression of these clones yielded 5 approximately 10 metabolites that were not detected in S . collinus culture extracts . This paper focusses on one of the new metabolites, termed collinone, that was isolated in large quantities and purified for spectroscopic structure determination and biological screening assays . Collinone is a heavily oxidized angular hexacyclic compound containing an unusual 1,4,5,8(2H,3H)-anthracenetetrone moiety previously only reported to be present in antibiotics SF2446A1, A2, A3, B1 and B2 isolated from Streptomyces sp . SF2446 . Structure analysis of collinone indicates a tridecaketide with a 26 carbon backbone . The basic benz{a}naphthacene ring system of collinone is angular, similar to the aglycones of the well-known angucycline and angucyclinone antibiotics . While collinone showed antibacterial activity against vancomycin-resistant enterococci, no antifungal or significant antiviral activities were detected . Collinone could be a good starting point to obtain new bioactive angucyclin(on)e-like compounds by further genetic engineering of its pathway.

Prog Transplant, 2001 Mar, 11(1), 17 - 22
Why is transmission of vancomycin-resistant enterococci on the increase?
Frohloff G.
Nosocomial infections continue to escalate in response to antibiotic usage and breaches in infection control practices . Historically, naturally occurring bacteria that cause infection when present in an unfamiliar environment have been successfully treated with antibiotics . However, antibiotic resistance has kept ahead of antibiotics and creates a situation in which infection no longer responds to antibiotics . In the (hypothetical) case presented in this article, a person entering a hospital for a simple procedure may acquire a nosocomial infection, with a resulting increase in morbidity and mortality . Reservoirs of enterococci naturally occur in animals and humans, although the misuse of antibiotics in humans and animals has given rise to enterococci resistance, namely vancomycin-resistant enterococci . Once established in these reservoirs, vancomycin-resistant enterococci are easily transmitted by direct or indirect mechanisms and are proving difficult to control in hospitals, other healthcare settings, and in the community.

N Engl J Med, 2001 May 10, 344(19), 1427 - 33
Control of vancomycin-resistant enterococcus in health care facilities in a region; Ostrowsky BE et al.; BACKGROUND: In late 1996, vancomycin-resistant enterococci were first detected in the Siouxland region of Iowa, Nebraska, and South Dakota . A task force was created, and in 1997 the assistance of the Centers for Disease Control and Prevention was sought in assessing the prevalence of vancomycin-resistant enterococci in the region's facilities and implementing recommendations for screening, infection control, and education at all 32 health care facilities in the region . METHODS: The infection-control intervention was evaluated in October 1998 and October 1999 . We performed point-prevalence surveys, conducted a case-control study of gastrointestinal colonization with vancomycin-resistant enterococci, and compared infection-control practices and screening policies for vancomycin-resistant enterococci at the acute care and long-term care facilities in the Siouxland region . RESULTS: Perianal-swab samples were obtained from 1954 of 2196 eligible patients (89 percent) in 1998 and 1820 of 2049 eligible patients (89 percent) in 1999 . The overall prevalence of vancomycin-resistant enterococci at 30 facilities that participated in all three years of the study decreased from 2.2 percent in 1997 to 1.4 percent in 1998 and to 0.5 percent in 1999 (P<0.001 by chi-square test for trend) . The number of facilities that had had at least one patient with vancomycin-resistant enterococci declined from 15 in 1997 to 10 in 1998 to only 5 in 1999 . At both acute care and long-term care facilities, the risk factors for colonization with vancomycin-resistant enterococci were prior hospitalization and treatment with antimicrobial agents . Most of the long-term care facilities screened for vancomycin-resistant enterococci (26 of 28 in 1998 {93 percent} and 23 of 25 in 1999 {92 percent}) and had infection-control policies to prevent the transmission of vancomycin-resistant enterococci (22 of 25 {88 percent} in 1999) . All four acute care facilities had screening and infection-control policies for vancomycin-resistant enterococci in 1998 and 1999 . CONCLUSIONS: An active infection-control intervention, which includes the obtaining of surveillance cultures and the isolation of infected patients, can reduce or eliminate the transmission of vancomycin-resistant enterococci in the health care facilities of a region.

J Bacteriol, 2001 Jun, 183(11), 3436 - 46
Regulation of expression of the vanD glycopeptide resistance gene cluster from Enterococcus faecium BM4339; Casadewall B et al.; A new open reading frame, encoding a putative integrase-like protein, was detected downstream from the six genes of the vanD glycopeptide resistance cluster in Enterococcus faecium BM4339 (B . Casadewall and P . Courvalin, J . Bacteriol . 181:3644-3648, 1999) . In this cluster, genes coding for the VanR(D)-VanS(D) two-component regulatory system were cotranscribed from the P(R(D)) promoter, whereas transcription of the vanY(D), vanH(D), vanD, vanX(D), and intD genes was initiated from the P(Y(D)) promoter located between vanS(D) and vanY(D) (the D subscript indicates that the gene is part of the vanD operon) . The VanR(D)-VanS(D) regulatory system is likely to activate transcription of the resistance genes from the promoter P(Y(D)) . Glycopeptide-susceptible derivatives of BM4339 were obtained by trans complementation of the frameshift mutation in the ddl gene, restoring functional D-alanine:D-alanine ligase activity in this strain . The glycopeptide-susceptible transformant BM4409, producing only D-alanyl-D-alanine-terminating peptidoglycan precursors, did not express the resistance genes encoding the VanY(D) D,D-carboxypeptidase, the VanH(D) dehydrogenase, the VanD ligase, the VanX(D) D,D-dipeptidase, and also the IntD integrase, although the regulatory region of the vanD cluster was still transcribed . In BM4409, the absence of VanR(D)-VanS(D), apparently dependent, transcription from promoter P(Y(D)) correlated with the lack of D-alanyl-D-lactate-terminating precursors . The vanX(D) gene was transcribed in BM4339, but detectable amounts of VanX(D) D,D-dipeptidase were not synthesized . However, the gene directed synthesis of an active enzyme when cloned on a multicopy plasmid in Escherichia coli, suggesting that the enzyme was unstable in BM4339 or that it had very low activity that was detectable only under conditions of high gene dosage . This activity is not required for glycopeptide resistance in BM4339, since this strain cannot synthesize D-alanyl-D-alanine.

Clin Infect Dis, 2001 Jun 1, 32(11), 1540 - 6 Epub 2001 Apr 30.
Clinical and epidemiological features of Enterococcus casseliflavus/flavescens and Enterococcus gallinarum bacteremia: a report of 20 cases; Reid KC et al.; The clinical significance of intrinsically vancomycin-resistant enterococci is not yet fully established, as these organisms are infrequently recovered from clinical specimens . We report our experience with 20 cases of Enterococcus gallinarum and Enterococcus casseliflavus/flavescens bacteremia in humans from 1992 through 1998 . Sixteen cases of bacteremia were caused by E . gallinarum . Underlying conditions were present in 19 (95%) of the patients and included malignancy, receipt of transplant, and Caroli's disease . Polymicrobial bacteremia was present in 9 patients (45%) . E . gallinarum and E . casseliflavus/flavescens, although they are infrequently isolated from clinical specimens, may cause serious invasive infections.

J Antimicrob Chemother, 2001 May, 47(5), 705 - 7
Effect of LY333328 against vancomycin-resistant Enterococcus faecium in a rat central venous catheter-associated infection model; Rupp ME et al.; A rat central venous catheter (CVC) infection model was used to assess the activity of LY333328 against vancomycin-resistant Enterococcus faecium (VRE) . Via the CVC, animals were challenged with 10(6) cfu of Enterococcus faecium with the VanA phenotype . Eight rats received a single dose of LY333328 and eight rats received saline . Seventy-five per cent of control animals had peripheral bacteraemia and 87.5% had VRE recovered from explanted CVCs at the time they were killed, as compared with 0 and 12.5%, respectively, of the LY333328-treated animals (P < 0.01) . All animals in the control group had evidence of metastatic disease compared with none of the treated group (P < 0.01) . LY333328 was effective against the strain of VRE tested in this model.

Lett Appl Microbiol, 2001 May, 32(5), 357 - 61
G1 antigen: a cell-surface immunoprotective 96 kDa glycoprotein from the virulent fish pathogen Enterococcus seriolicida, its purification and characterization; Alim SR et al.; Strains of the fish pathogen Enterococcus seriolicida were identified as agglutinating and non-agglutinating, according to their reaction with anti-serum raised against type strain YT-3 (ATCC49156) . The non-agglutinating strains are highly pathogenic in contrast to agglutinating strains . A 96 kDa immunoprotective glycoprotein G1 antigen from non-agglutinating Ent . seriolicida strain SS91-014 (N) was purified and characterized . The purification procedure entailed extraction of antigen by glass bead agitation, 80% (NH4)(2)SO4 precipitation, gel filtration and electroelution . An immunofluorescence microscopy study using monoclonal antibody M3A5 raised against G1 antigen revealed that G1 antigen is present only on the cell surface of non-agglutinating strains . Therefore, the G1 antigen of virulent Ent . seriolicida could be a potential candidate for protective vaccine against enterococcosis in fish.

J Clin Microbiol, 2001 May, 39(5), 1781 - 7
Outbreak of vancomycin-resistant Enterococcus faecium of the phenotype VanB in a hospital in Warsaw, Poland: probable transmission of the resistance determinants into an endemic vancomycin-susceptible strain; Kawalec M et al.; The first outbreak caused by vancomycin-resistant enterococci of the VanB phenotype in Poland was analyzed . It occurred in a single ward of a Warsaw hospital which is a specialized center for the treatment of hematological disorders . Between July 1999 and February 2000, 11 patients in the ward were found to be infected and/or colonized by Enterococcus faecium that was resistant in vitro to vancomycin and susceptible to teicoplanin . PCR analysis confirmed that the vancomycin-resistant E . faecium (VREM) isolates carried the vanB gene, which is responsible for the VanB phenotype . Pulsed-field gel electrophoresis (PFGE) typing revealed that the isolates belonged to four distinct PFGE types and that one of these was clearly predominant, including isolates collected from seven different patients . The isolates contained one or more copies of the vanB gene cluster of the identical, unique DraI/PagI (BspHI) restriction fragment length polymorphism type, which resided in either the same or different plasmid molecules or chromosomal regions . All this data suggested that the outbreak was due to both clonal spread of a single strain and horizontal transfer of resistance genes among nonrelated strains, which could be mediated by plasmids and/or by vanB gene cluster-containing transposons . The comparative analysis of vancomycin-susceptible E . faecium (VSEM) isolates collected from infections in the same ward at the time of the VREM outbreak has led to identification of a widespread VSEM strain that was possibly related to the major VREM clone . It is very likely that this endemic VSEM strain has acquired vancomycin-resistance determinants and that the acquisition occurred more than once during the outbreak.

J Clin Microbiol, 2001 May, 39(5), 1763 - 70
Classification and identification of enterococci: a comparative phenotypic, genotypic, and vibrational spectroscopic study; Kirschner C et al.; Rapid and accurate identification of enterococci at the species level is an essential task in clinical microbiology since these organisms have emerged as one of the leading causes of nosocomial infections worldwide . Vibrational spectroscopic techniques (infrared {IR} and Raman) could provide potential alternatives to conventional typing methods, because they are fast, easy to perform, and economical . We present a comparative study using phenotypic, genotypic, and vibrational spectroscopic techniques for typing a collection of 18 Enterococcus strains comprising six different species . Classification of the bacteria by Fourier transform (FT)-IR spectroscopy in combination with hierarchical cluster analysis revealed discrepancies for certain strains when compared with results obtained from automated phenotypic systems, such as API and MicroScan . Further diagnostic evaluation using genotypic methods-i.e., PCR of the species-specific ligase and glycopeptide resistance genes, which is limited to the identification of only four Enterococcus species and 16S RNA sequencing, the "gold standard" for identification of enterococci-confirmed the results obtained by the FT-IR classification . These results were later reproduced by three different laboratories, using confocal Raman microspectroscopy, FT-IR attenuated total reflectance spectroscopy, and FT-IR microspectroscopy, demonstrating the discriminative capacity and the reproducibility of the technique . It is concluded that vibrational spectroscopic techniques have great potential as routine methods in clinical microbiology.

Lancet . 2001 Apr 14;357(9263):1179.
Infections due to vancomycin-resistant Enterococcus faecium resistant to linezolid; Gonzales RD et al.; Linezolid is a new oxazolidinone antibiotic used to treat infections caused by vancomycin-resistant enterococci (VRE) . In early clinical trials, emergence of resistance occurred rarely . We report clinical details and antibiotic susceptibility from five patients treated with linezolid for VRE infections who had resistant organisms isolated during therapy . Four were transplant patients receiving protracted courses of the drug; three cases were associated with treatment failure . One of 45 linezolid-treated patients developed resistance during therapy . Susceptibility testing should be done in all cases on starting therapy.

Int J Syst Evol Microbiol, 2001 Mar, 51(Pt 2), 393 - 400
Enterococcus villorum sp . nov., an enteroadherent bacterium associated with diarrhoea in piglets; Vancanneyt M et al.; The taxonomic positions of five enteroadherent bacterial pig isolates, showing phenotypic characteristics most similar to those of Enterococcus durans and Enterococcus hirae, were investigated in a polyphasic study that included 16S rDNA sequence analysis, DNA-DNA hybridizations, DNA base-ratio determinations, whole-cell protein fingerprinting, D11344-primed PCR typing and an extensive examination of phenotypic properties . The results demonstrated that the organisms represent a new species in the Enterococcus faecium species group, for which the name Enterococcus villorum sp . nov . is proposed . The type strain is LMG 12287T (= CCM 4887T).

Clin Infect Dis, 2001 May 15, 32 Suppl 2, S133 - 45
Clinical prevalence, antimicrobial susceptibility, and geographic resistance patterns of enterococci: results from the SENTRY Antimicrobial Surveillance Program, 1997-1999; Low DE et al.; As part of the SENTRY Antimicrobial Resistance Surveillance Program, a total of 4998 strains of enterococci isolated from 1997 to 1999 were processed . The occurrence of enterococcal infections by species and site of infection was analyzed, as were the occurrence of vancomycin-resistant enterococci (VRE) and their resistance phenotypes and genotypes . Trends in antimicrobial susceptibility to a variety of agents (including experimental compounds) were also reported . Enterococci accounted for >9% of isolates from all bloodstream infections (BSIs) in North America . Ampicillin was active against strains from Latin America and Europe but not against those from the United States and Canada . US isolates were considerably more resistant to vancomycin (17% resistant strains in 1999) than were those from patients in the rest of the world . The highest proportion of VRE was observed among BSI isolates (81.7%) . Quinupristin-dalfopristin, chloramphenicol, and doxycycline were the most active agents tested against VRE . The results of this study confirm the worldwide trend in increasing occurrence of enterococci and the emerging pattern of antimicrobial resistance among such isolates.

Infect Control Hosp Epidemiol, 2001 Mar, 22(3), 140 - 7
A hospital epidemic of vancomycin-resistant Enterococcus: risk factors and control; Byers KE et al.; OBJECTIVE: To determine risk factors for vancomycin-resistant Enterococcus (VRE) colonization during a hospital outbreak and to evaluate Centers for Disease Control and Prevention (CDC)-recommended control measures . DESIGN: Epidemiological study involving prospective identification of colonization and a case-control study . SETTING: A university hospital . PARTICIPANTS: Patients on eight wards involved in outbreak from late 1994 through early 1995 . METHODS: Cases were matched by ward and culture date with up to two controls . Risk factors were evaluated with four multivariate models using conditional logistic regression . The first evaluated proximity to other VRE patients and isolation status . The second evaluated proximity to unisolated VRE cases and three variables independently predictive after adjustment for proximity . The third evaluated seven significant univariate predictors in addition to proximity to unisolated VRE in backward, stepwise logistic regression . The fourth assessed proximity to VRE with all other variables collected, clustered in a principal components analysis . Pulsed-field gel electrophoresis was performed to assess clonality of two outbreak strains . RESULTS: The incidence of transmission declined significantly after CDC guidelines were implemented . Proximity to unisolated VRE cases during the prior week was a significant predictor of acquisition in each of four multivariate models . Other significant risk factors in multivariate models included a history of major trauma and treatment with metronidazole . Pulsed-field gel electrophoresis confirmed the clonality of two outbreak strains . CONCLUSIONS: VRE was transmitted between patients during a hospital epidemic, with proximity to previously unisolated VRE patients being an important risk factor . Weekly surveillance cultures and contact isolation of colonized patients significantly reduced spread

Nippon Rinsho, 2001 Apr, 59(4), 733 - 8
{Combination therapy against vancomycin-resistant enterococci}; Kariyama R et al.; The therapeutic options for patients infected with vancomycin-resistant enterococci are limited . Optimal therapy for serious enterococcal infections requires the use of synergistic combinations of a cell wall-active agent plus an aminoglycoside . Enterococci have acquired aminoglycoside resistance genes that mediate production of aminoglycoside-modifying enzymes, which eliminate this synergistic bactericidal effect . Traditional therapy has been compromised due to the increasing prevalence of enterococci with beta-lactam, glycopeptide, and high-level gentamicin resistance . Arbekacin, a semi-synthetic aminoglycoside, shows excellent activity against a wide variety of bacteria that produce aminoglycoside modifying enzymes, including AAC(6')-APH(2") . In recent studies, the combination of ampicillin and arbekacin demonstrated inhibitory activity against vancomycin-resistant enterococci, and may prove useful in the treatment of enterococcal infections where treatment options are limited.

Clin Infect Dis, 2001 May 1, 32(9), 1384 - 5 Epub 2001 Apr 13.
Probiotic Enterococcus faecium strain is a possible recipient of the vanA gene cluster; Lund B et al.; The characteristics of Enterococcus faecium have led to concern regarding the safety of probiotics that contain this bacterium . The results of an in vitro filter mating assay indicate that a probiotic E . faecium strain might be a potential recipient of vancomycin resistance genes.

Clin Infect Dis, 2001 May 1, 32(9), 1381 - 3 Epub 2001 Apr 09.
Recurrent vancomycin-resistant Enterococcus bacteremia: prevalence, predisposing factors, and strain relatedness; Baran J Jr et al.; We studied the prevalence of recurrent vancomycin-resistant Enterococcus (VRE) bacteremia, predisposing factors, and strain relatedness during a 3 year period at our institution . Of 36 inpatients who had episodes of bacteremia, 3 (8.3%) had recurrent episodes . Predisposing factors were mucositis and neutropenia (1 patient) and chronic renal failure requiring hemodialysis (2) . Recurrent episodes separated by < or = 3 months were caused by identical or related strains, and those at greater intervals by distinct strains . Recurrent VRE bacteremia is uncommonPublication Types:

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