FEMS Microbiol Lett, 1999 Apr 1, 173(1), 265 - 71 In situ inversion of the conjugative transposon Tn916 in Enterococcus faecium DPC3675; O'Keeffe T et al.; Enterococcus faecium DPC3675 is a derivative of E . faecium DPC1146 which contains a single copy of the conjugative transposon Tn916 . Although the transposon is observed to be oriented in one direction in individual colonies, DNA extracted from cultures grown from these colonies contains the transposon in both orientations, as determined by PCR analysis and sequencing of the transposon/chromosome junctions . Therefore, Tn916 possesses a hitherto unreported ability to invert within a particular insertion site during growth in broth. Chest, 1999 Apr, 115(4), 1085 - 91 The incidence of and clinical variables associated with vancomycin-resistant enterococcal colonization in mechanically ventilated patients; Bhorade SM et al.; STUDY OBJECTIVES: (1) To determine in our ICU the incidence of vancomycin-resistant enterococcus (VRE) colonization in mechanically ventilated patients without a history of VRE infection or colonization; and (2) to determine the risk factors and outcome variables associated with VRE colonization in these patients . DESIGN: A prospective cohort study conducted between January 1996 and March 1998 . SETTING: Medical and cardiac critical care units in a tertiary care urban university hospital . PATIENTS: Mechanically ventilated patients without evidence of pneumonia at the onset of ventilation . INTERVENTIONS: None . MEASUREMENTS AND RESULTS: Patients underwent rectal cultures by standard methods on day 1, day 3 or 4, day 6 or 7, and day 14 of intubation to detect VRE . Thirteen of 83 patients (16%) had rectal cultures positive for VRE (VRE+) at some point while being mechanically ventilated during their stay in the ICU . In comparison, approximately 15 of 2,100 medical ICU patients (0.7%) had clinical VRE infections as determined by the hospital's infection control program during a 2-year period . VRE+ patients had a higher incidence of immunosuppression than patients who had rectal cultures negative for VRE (VRE-) (9 of 13 {69%} vs 16 of 70 {23%}, respectively; p < 0.01) and neutropenia (4 of 13 {31%} vs 5 of 70 {7%}, respectively; p < 0.01) . Hospital length of stay (LOS) was longer in VRE+ patients than in VRE- patients (27+/-17 days vs 17+/-14 days, respectively; p = 0.05), whereas pre-ICU hospital LOS and ICU LOS were similar in both patient groups . Five of 67 patients (7%) were VRE+ on day 1 of intubation, suggesting colonization at a prior site of care . Three of 29 patients who had subsequent rectal cultures converted to VRE+ while in the ICU . This group had a higher incidence of immunosuppression and neutropenia, and received more vancomycin compared with the patients who remained VRE- (p < 0.01) . However, there was no significant difference in the use of other broad-spectrum antibiotics (such as antipseudomonal penicillins, third-generation cephalosporins, quinolones, and clindamycin), enteral tube feedings, or sucralfate between the two groups . In addition, a topical antibiotic paste (a gentamicin, nystatin, polymixin slurry) that was placed in the oropharynx to prevent bacterial overgrowth was not found to increase the incidence of VRE colonization in this patient population . CONCLUSIONS: The incidence of VRE colonization was surprisingly high: 16% in mechanically ventilated patients in a hospital in which VRE was not previously known to be endemic . Risk factors for the acquisition of VRE colonization included immunosuppression, neutropenia, and vancomycin use . Increased LOSs and hospital costs were seen in VRE+ patients compared to VRE- patients . Whether VRE colonization is a contributor to severe disease that leads to prolonged hospitalization and increased resource allocation or whether it is simply a marker of disease severity cannot be determined from this study . To the extent that specific antibiotic protocols are used to reduce antibiotic-resistant flora in the ICU, monitoring the incidence of VRE in the stool specimens of immunocompromised, mechanically ventilated patients can be a simple and useful tool to assess one effect of these strategies. J Clin Microbiol, 1999 May, 37(5), 1638 - 41 Survey of antibiotic resistance among enterococci in North Rhine-Westphalia, Germany; Reinert RR et al.; A surveillance study on antibiotic resistance of enterococcal isolates (n = 730) was carried out in North Rhine-Westphalia, Germany, in 1997 . Resistance rates to ampicillin (7.4%), high-level gentamicin (15.0%), high-level streptomycin (27.9%), ciprofloxacin (37.9%), vancomycin (1.5%), and teicoplanin (1.5%) were determined . All vancomycin-resistant enterococci (VRE) carried the vanA gene . SmaI and ApaI macrorestriction patterns indicated an intra- and interhospital spread of VRE. Br J Biomed Sci, 1998 Jun, 55(2), 149 - 56 The emergence of enterococci as a cause of nosocomial infection; Hunt CP; Enterococci have traditionally been regarded as low-grade pathogens but have emerged as an increasingly important cause of nosocomial infection . The rise in hospital-acquired enterococcal infection has been in part due to the increased use of broad-spectrum antibiotics and the rising number of severely ill patients . The intrinsic resistance of enterococci to many antimicrobial agents, and the acquisition of resistance to the few antibiotics available for treatment, has led to real therapeutic difficulties . The microbiological laboratory has an important role to play in the control of enterococcal infection through surveillance, and should be able to identify antibiotic-resistant strains likely to cause a problem . Infection control measures, such as source isolation of infected or colonised patients, should be considered . The possibility that vancomycin-resistant strains of enterococci are entering the community via the food chain indicates the need for greater control of the use of glycopeptide antibiotics in animal feed. Am J Infect Control, 1999 Apr, 27(2), 84 - 91 Improving the appropriateness of vancomycin use by sequential interventions; Lipsky BA et al.; BACKGROUND: Vancomycin usage is directly associated with the incidence of vancomycin-resistant enterococci . Optimal methods to reduce inappropriate use have not been delineated . We determined the appropriateness of vancomycin prescribing at our hospital on the basis of national guidelines and assessed the effect of sequential administrative and educational interventions . METHODS: In this prospective 3-phase study conducted in a Veterans Affairs Medical Center, we monitored vancomycin prescribing at baseline and in 2 follow-up periods . Administrative interventions included discussions with service chiefs and revising routine perioperative antibiotic prophylaxis orders . Educational interventions included in-services about vancomycin-resistant enterococci and appropriate vancomycin prescribing . In each monitoring period, 50 consecutive new vancomycin orders that could be evaluated were classified for appropriateness and categorized by indication . RESULTS: At baseline, 70% of vancomycin use was inappropriate . Surgical services accounted for 84% of orders . Interventions targeted services with high or frequently inappropriate vancomycin use . After administrative interventions, inappropriate vancomycin use dropped to 40% of orders (P =.003) . Improvements were noted in targeted services . Educational interventions further decreased inappropriate vancomycin use, but the effect appeared transient . CONCLUSIONS: The simple, nonrestrictive administrative interventions used resulted in a statistically significant (30%) reduction in inappropriate vancomycin prescribing . However, educational interventions provided only transient benefit on institutional prescribing patterns. J Microbiol Methods, 1999 Mar, 35(2), 95 - 100 Reverse transcription polymerase chain reaction method for the detection of glycopeptide resistance in enterococci; Privitera O et al.; In this work we have developed reverse transcription polymerase chain reaction (RT-PCR) methods for detecting specific mRNA from enterococci, particularly vanA and vanB genes, responsible for glycopeptide resistance in this genus . mRNA from the two genes was detected immediately after RNA extraction of a midlog phase culture, determined by growth rate analysis . Because of the short half-life associated with many bacterial RNA species (1.5-2 min), time is an important factor in obtaining RNA of good yield and high purity . Our results showed that: (i) the transcription of mRNA related to vanA ligase in enterococci showing Van A phenotype happens only after induction with both vancomycin and teicoplanin; (ii) the transcription of mRNA related to vanB ligase happens only in the presence of vancomycin and (iii) there was no transcription of mRNA in the two strains positive to vanA gene after PCR experiments . RT-PCR methodology can have numerous applications in microbiology for studying gene expression in isolated bacteria and also in nonculturable cells in environmental samples, for studies of mechanisms and/or as an indicator of viability in bacterial communities. Syst Appl Microbiol, 1999 Feb, 22(1), 9 - 21 Determination of the nucleotide sequence of the 23S ribosomal RNA and flanking spacers of an Enterococcus faecium strain, reveals insertion-deletion events in the ribosomal spacer 1 of enterococci; Naimi A et al.; The usefulness of 16S-23S (ITS1) and 23S-5S (ITS2) ribosomal spacer nucleotide sequence determination, as a complementary approach to the biochemical tests traditionally used for enterococcal species identification, is shown by its application to the identification of a strain, E27, isolated from a natural bacteria mixture used for cheese production . Using combined approaches we showed, unambiguously, that strain E27 belongs to the Enterococcus faecium species . However, its ITS1 region has an interesting peculiarity . In our previous study of ITS1s from various enterococcal species (NAIMI et al., 1997, Microbiology 143, 823-834), the ITS1s of the two E . faecium strains studied, were found to contain an additional 115-nt long stem-loop structure as compared to the ITS1s of other enterococci, only one out of the 3 ITS1s of E . hirae ATCC 9790, was found to contain a similar 107-nt long stem-loop structure . The ITS1 of strain E27 is 100% identical to that of E . faecium ATCC 19434T, except that the 115-nt additional fragment is absent . This strongly suggests the existence of lateral DNA transfer or DNA recombination events at a hot spot position of the ITS1s from E . faecium and E . hirae . Small and large ITS1 nucleotide sequence determination for strain E27 generalized the notion of two kinds of ITSs in enterococci: one with a tRNA(Ala) gene, one without tRNA gene . To complete strain E27 characterization, its 23S rRNA sequence was established . This is the first complete 23S rRNA nucleotide sequence determined for an enterococcal species. Appl Environ Microbiol, 1999 Apr, 65(4), 1777 - 80 Genomic relationships between Enterococcus faecium strains from different sources and with different antibiotic resistance profiles evaluated by restriction endonuclease analysis of total chromosomal DNA using EcoRI and PvuII; Quednau M et al.; Forty-seven Enterococcus faecium strains from different sources were evaluated by restriction endonuclease analysis (REA) of total chromosomal DNA . Strains from chicken, pork, and humans were clearly divided into separate clusters, whereas strains from different countries, strains with different antibiotic resistance profiles, or clinical and healthy-subject strains were not. Infect Control Hosp Epidemiol, 1999 Mar, 20(3), 171 - 5 The prevalence of colonization with vancomycin-resistant Enterococcus at a Veterans' Affairs institution; Tokars JI et al.; OBJECTIVE: To study vancomycin-resistant Enterococcus (VRE) prevalence, risk factors, and clustering among hospital inpatients . DESIGN: Rectal-swab prevalence culture survey conducted from February 5 to March 22, 1996 . SETTING: The Veterans' Affairs Medical Center, Atlanta, Georgia . PATIENTS: Hospital (medical and surgical) inpatients . RESULTS: The overall VRE prevalence was 29% (42/147 patients) . The VRE prevalence was 52% (38/73 patients) among patients who had received at least one of six specific antimicrobials during the preceding 120 days, compared with only 5% (4/74) among those who had not received the antimicrobials (relative risk, 9.6; P<.001) . The longer the period (up to 120 days) during which antimicrobial use was studied, the more closely VRE status was predicted . Among 67 hospital patients in 28 multibed rooms, clustering of VRE among current roommates was not found . CONCLUSIONS: At this hospital with relatively high VRE prevalence, VRE colonization was related to antibiotic use but not to roommate VRE status . In hospitals with a similar VRE epidemiology, obtaining cultures from roommates of VRE-positive patients may not be as efficient a strategy for identifying VRE-colonized patients as obtaining screening cultures from patients who have received antimicrobials. Yonsei Med J, 1998 Dec, 39(6), 562 - 8 Vancomycin-resistant enterococcal infections in Korea; Kim JM et al.; Enterococci recently became the second-to-third most commonly isolated organism from nosocomial infections . Enterococci are intrinsically more resistant to many antimicrobial agents and often show acquired resistance to many antimicrobial agents including high-level aminoglycosides . With the increased use of vancomycin, vancomycin-resistant enterococci (VRE) has become an important nosocomial pathogen . In Korea, the proportion of VRE among all enterococcal of VRE is no longer low in some settings and recent observations of a sudden increase of VRE isolation in several hospitals in Korea suggests that VRE infection may become a serious problem in the near future . The most important considerations are that vancomycin-resistant genes may spread to other highly virulent genera, such as MRSA, and that there are no approved and convincingly effective antibiotics for the treatment of VRE . Therefore, current efforts have concentrated on limiting the spread of these organisms within the hospital environment . Prudent use of antimicrobial agents and strict adherence to preventive measures such as aggressive communication, education, and infection control practices are essential to control the spread of this organism . However, hospital infection control protocols and the laboratory support they require are costly in terms of space and supplies, as well as in personnel resources . These factors add further pressure to already stretched hospital budgets . Nevertheless, policies or programs defining and managing VRE infection or colonization should be established and now is the time to enforce an overall management strategy against VRE. Yonsei Med J, 1998 Dec, 39(6), 554 - 61 Antimicrobial resistance in enterococci; Pai CH et al.; Enterococci have emerged as a major nosocomial pathogen and as an ever-increasing problem in antimicrobial resistance . They are ubiquitous in the intestinal flora of humans and animals and inherently resistant to a wide array of antimicrobial agents, and, more alarmingly, they seem to have a potential facility for acquiring new resistance determinants, including beta-lactamase production, high-level resistance to aminoglycosides, and recently, glycopeptide resistance . Collectively, all of these properties make enterococci one of most difficult nosocomial pathogens to treat and control today . The purpose of this review was to examine the epidemiology, the mechanisms, and laboratory detection of resistance of enterococci to the two major groups of antibiotics: aminoglycosides and glycopeptides. HNO, 1999 Jan, 47(1), 25 - 32 {Modification of bacterial growth by alloplastic bone substitutes}; Geyer G et al.; BACKGROUND: To determine the applicability of alloplastic materials as bone substitutes it is now standard procedure to test materials for possible toxic effects and to study their behavior in animal models and cell cultures . This is especially important with respect to middle ear implants that can be put at risk by recurrent infections and require additional testing in a bacterially contaminated environment . MATERIALS AND METHODS: In the present study ionomeric cement (V-O CEM), bioactive glass ceramic and hydroxyapatite were subjected to contamination with S . aureus, E . coli, Pr . mirabilis, Ps . aeruginosa and Enterococci using agar diffusion and microbial suspension tests and examined for their antibacterial activity . A special feature of V-O CEM that had to be considered was that it could be implanted in two physical states (as a viscous substance and a fully hardened material) . RESULTS: The agar diffusion test showed that an antibacterial effect of freshly mixed V-O CEM was demonstrable for up to 60 min . In the microbial suspension test growth of E . coli was found to be promoted after 48-h incubation by V-O CEM set for 1 h . S . aureus exhibited a depressed growth, while Pseudomonas cultures demonstrated cell death after 48 h . V-O CEM set for 24 h and 7 days, respectively, exerted a similar though less pronounced effect . Using the microbial suspension test, a comparison was also made of the antibacterial activities of 24-h V-O CEM, bioactive glass ceramic and hydroxyapatite against cultures of S . aureus, Pseudomonas and E . coli . The inhibitory effect of hydroxyapatite on the growth of S . aureus was found to persist beyond the 48-h incubation period . There was slight growth of E . coli in the presence of bioactive glass ceramic after 48 h, whereas hydroxyapatite produced inhibition of microbial growth . V-O CEM inhibited the growth of Pseudomonas, unlike bioactive glass ceramic and hydroxyapatite, which transiently promoted bacterial growth . DISCUSSION AND CONCLUSIONS: Our findings showed that V-O CEM, bioactive glass ceramic and hydroxyapatite exhibited material-dependent bacterial colonization and thus resembled polymeric bone substitutes (susceptible to invasion by S . epidermidis) and metals (sensitive to S . aureus) . In general, users of bone substitutes should conduct preclinical tests in order to obtain advance information on the properties of possible replacement material . Since there can be varying interactions between the materials studied and bacterial growth, material-specific effects on bacterial growth should be investigated . While it is recognized that in vitro studies are an inadequate simulation of the clinical situation, they still provide some insight into the likely behavior of a bone substitutes in human sites. Pediatr Cardiol, 1999 May-Jun, 20(3), 227 - 8 Enterococcus avium endocarditis in an infant with tetralogy of Fallot; Swaminathan S et al.; We report a case of infective endocarditis secondary to Enterococcus avium in a 1-year-old infant with tetralogy of Fallot and a Blalock-Taussig shunt . To our knowledge, this is the first case of E . avium endocarditis to be reported. Emerg Infect Dis, 1999 Jan-Feb, 5(1), 143 - 6 Proficiency of clinical laboratories in and near Monterrey, Mexico, to detect vancomycin-resistant enterococci; McDonald LC et al.; Early detection of vancomycin-resistant enterococci is important for preventing its spread among hospitalized patients . We surveyed the ability of eight hospital laboratories in and near Monterrey, Mexico, to detect vancomycin resistance in Enterococcus spp . and found that although laboratories can reliably detect high-level vancomycin resistance, many have difficulty detecting low-level resistance. J Clin Microbiol, 1999 Apr, 37(4), 1084 - 91 DNA banding pattern polymorphism in vancomycin-resistant Enterococcus faecium and criteria for defining strains; Morrison D et al.; The degree of DNA banding pattern polymorphism exhibited by vancomycin-resistant Enterococcus faecium (VREM) strains isolated on a renal unit over an 11-month period was investigated . Thirty VREM strains from different patients were analyzed by pulsed-field gel electrophoresis (PFGE; with extended run and optimal pulse times), ribotyping, plasmid profile analysis, biotyping, pyrolysis mass spectrometry, and antibiogram analysis . PFGE resolved 17 banding patterns which formed four distinct clusters at the 82% similarity level . Intercluster band differences ranged from 14 to 31 bands . The strains in one cluster, which contained seven patterns that differed from each other by one to seven bands and from the common pattern by five bands, were confirmed to be a single strain by four of the five other typing methods . The strains in a second cluster with eight patterns, which differed from each other by 1 to 12 bands, contained two subclusters . This subdivision was supported by ribotyping and biotyping . However, it was unclear whether these subclusters represented distinct strains . In one strain, marked polymorphism (patterns that differed from each other by up to four bands) was observed in the ribotype pattern . This study demonstrates the high degree of DNA banding pattern polymorphism found for some strains of VREM and illustrates the complexity involved in defining such strains. Chem Biol, 1999 Mar, 6(3), 177 - 87 Mutational analysis of active-site residues of the enterococcal D-ala-D-Ala dipeptidase VanX and comparison with Escherichia coli D-ala-D-Ala ligase and D-ala-D-Ala carboxypeptidase VanY; Lessard IA et al.; BACKGROUND: Vancomycin-resistant enterococci are pathogenic bacteria that attenuate antibiotic sensitivity by producing peptidoglycan precursors that terminate in D-Ala-D-lactate rather than D-Ala-D-Ala . A key enzyme in effecting antibiotic resistance is the metallodipeptidase VanX, which reduces the cellular pool of the D-Ala-D-Ala dipeptide . RESULTS: We constructed eleven mutants, using the recently determined VanX structure as a basis, to investigate residue function . Mutating Asp142 or Ser114 showed a large effect principally on KM, consistent with roles in recognition of the D-Ala-D-Ala termini . The drastic reduction or absence of activity in the Arg71 mutants correlates with a role in the stabilization of an anionic tetrahedral transition state . Three residues of the Escherichia coli D-Ala-D-Ala ligase (Ddl), Glu15, Ser 281 and Arg255, are similarly conserved and have equivalent functions with respect to VanX, consistent with a convergent evolution of active sites to bind D-Ala-D-Ala and lower energy barriers for formation of the tetrahedral intermediate and transition states . In the N-acyl-D-Ala-D-Ala carboxypeptidase VanY, all active-site residues are conserved (except for the two responsible for recognition of the dipeptide amino terminus) . CONCLUSIONS: The mutagenesis results support structure-based functional predictions and explain why the VanX dipeptidase and Ddl ligase show narrow specificity for the D,D-dipeptide substrate . The results reveal that VanX and Ddl, two enzymes that use the same substrate but proceed in opposite directions driven by distinct cofactors (zinc versus ATP), evolved similar architectural solutions to substrate recognition and catalysis acceleration . VanY sequence analysis predicts an active site and mechanism of reaction similar to VanX. Biochemistry, 1999 Mar 9, 38(10), 3000 - 11 Equilibrium analyses of the active-site asymmetry in enterococcal NADH oxidase: role of the cysteine-sulfenic acid redox center; Mallett TC et al.; Recent studies {Mallett, T . C., and Claiborne, A . (1998) Biochemistry 37, 8790-8802} of the O2 reactivity of C42S NADH oxidase (O2 --> H2O2) revealed an asymmetric mechanism in which the two FADH2.NAD+ per reduced dimer display kinetic inequivalence . In this report we provide evidence indicating that the fully active, recombinant wild-type oxidase (O2 --> 2H2O) displays thermodynamic inequivalence between the two active sites per dimer . Using NADPH to generate the free reduced wild-type enzyme (EH2'/EH4), we have shown that NAD+ titrations lead to differential behavior as only one FADH2 per dimer binds NAD+ tightly to give the charge-transfer complex . The second FADH2, in contrast, transfers its electrons to the single Cys42-sulfenic acid (Cys42-SOH) redox center, which remains oxidized during the reductive titration . Titrations of the reduced NADH oxidase with oxidized 3-acetylpyridine and 3-aminopyridine adenine dinucleotides further support the conclusion that the two FADH2 per dimer in wild-type enzyme can be described as distinct "charge-transfer" and "electron-transfer" sites, with the latter site giving rise to either intramolecular (Cys42-SOH) or bimolecular (pyridine nucleotide) reduction . The reduced C42S mutant is not capable of intramolecular electron transfer on binding pyridine nucleotides, thus confirming that the Cys42-SOH center is in fact the source of the redox asymmetry observed with wild-type oxidase . These observations on the role of Cys42-SOH in the expression of thermodynamic inequivalence as observed in wild-type NADH oxidase complement the previously described kinetic inequivalence of the C42S mutant; taken together, these results provide the overlapping framework for an alternating sites cooperativity model of oxidase action. FEBS Lett, 1999 Feb 19, 445(1), 27 - 30 The Enterococcus hirae copper chaperone CopZ delivers copper(I) to the CopY repressor; Cobine P et al.; Expression of the cop operon which effects copper homeostasis in Enterococcus hirae is controlled by the copper responsive repressor CopY . Purified Zn(II)CopY binds to a synthetic cop promoter fragment in vitro . Here we show that the 8 kDa protein CopZ acts as a copper chaperone by specifically delivering copper(I) to Zn(II)CopY and releasing CopY from the DNA . As shown by gel filtration and luminescence spectroscopy, two copper(I) are thereby quantitatively transferred from Cu(I)CopZ to Zn(II)CopY, with displacement of the zinc(II) and transfer of copper from a non-luminescent, exposed, binding site in CopZ to a luminescent, solvent shielded, binding site in CopY. Infect Control Hosp Epidemiol, 1999 Feb, 20(2), 106 - 9 Control of vancomycin-resistant enterococci at a community hospital: efficacy of patient and staff cohorting; Jochimsen EM et al.; OBJECTIVE: To evaluate the efficacy of patient and staff cohorting to control vancomycin-resistant enterococci (VRE) at an Indianapolis community hospital . DESIGN: To interrupt transmission of VRE, a VRE point-prevalence survey of hospital inpatients was conducted, and VRE-infected or -colonized patients were cohorted on a single ward with dedicated nursing staff and patient-care equipment . To assess the impact of the intervention, staff compliance with contact isolation procedures was observed, and the VRE point-prevalence survey was repeated 2 months after the cohort ward was established . RESULTS: Following the establishment of the cohort ward, VRE prevalence among all hospitalized inpatients decreased from 8.1% to 4.7% (25 positive cultures among 310 patients compared to 13 positive cultures among 276 patients, P=.14); VRE prevalence among patients whose VRE status was unknown before cultures were obtained decreased from 5.9% to 0.8% (18 positive cultures among 303 patients compared to 2 positive cultures among 262 patients, P=.002); and observed staff-patient interactions compliant with published isolation recommendations increased (5 {22%} of 23 interactions compared to 36 {88%} of 41 interactions, P<.0001) . CONCLUSIONS: Our data suggest that, in hospitals with endemic VRE or continued VRE transmission despite implementation of contact isolation measures, establishing a VRE cohort ward may be a practical and effective method to improve compliance with infection control measures and thereby to control epidemic or endemic VRE transmission. J Hosp Infect, 1999 Feb, 41(2), 137 - 43 Isolation and epidemiological study of vancomycin-resistant Enterococcus faecium from patients of a haematological unit in Poland; Samet A et al.; Enterococcus faecium has recently emerged as a serious nosocomial pathogen . Vancomycin resistant enterococci (VRE) have been isolated in Europe and the USA since 1988 . This is the first report on isolation of vancomycin resistant E . faecium (VREM) strains in Poland, from Haematological Unit patients in the Clinical Hospital in Gdansk . In total, 6412 samples were examined between December 1996 and October 1997 . Five hundred and five isolates of Enterococcus spp . were collected . One hundred and one were classified as Enterococcus faecium of which 49 were resistant to vancomycin (MIC > 256 mg/L) and teicoplanin (MIC > 256 mg/L), characteristic of the VanA phenotype . Twenty-nine patients were infected or colonized . A PCR-based specific diagnostic assay confirmed the phenotype . The multiplex PCR-restriction fragment length polymorphism patterns were consistent with VanA-type of vancomycin-resistant E . faecium for all isolates examined . These isolates were epidemiologically-related as shown by PCR-fingerprinting. Antimicrob Agents Chemother, 1999 Mar, 43(3), 592 - 7 Synergy of an investigational glycopeptide, LY333328, with once-daily gentamicin against vancomycin-resistant Enterococcus faecium in a multiple-dose, in vitro pharmacodynamic model; Zelenitsky SA et al.; The pharmacodynamics of an investigational glycopeptide, LY333328 (LY), alone and in combination with gentamicin, against one vancomycin-susceptible and two vancomycin-resistant Enterococcus faecium strains were studied with a multiple-dose, in vitro pharmacodynamic model (PDM) . Dose-range data for the PDM studies were obtained from static time-kill curve studies . In PDM experiments conducted over 48 h, peak LY concentrations of 0.1x and 1x the MIC every 24 h and peak gentamicin concentrations of 18 micrograms/ml every 24 h (Gq24 h) and 6 micrograms/ml every 8 h (Gq8 h) were studied alone and in the four possible LY-gentamicin combinations . Compared to either antibiotic alone, LY-gentamicin combination regimens produced significantly higher apparent killing rates (KRs) calculated during the initial 2 h postdosing . The mean KRs for LY or gentamicin alone versus those for the LY-gentamicin combination regimens were 0.35 +/- 0.55 log10 CFU/ml/h (95% confidence interval {CI95%}, 0 to 0.70) and 1.46 +/- 0.71 log10 CFU/ml/h (CI95%, 1.01 to 1.91), respectively (P < 0.0001) . Bacterial killing at 48 h (BK48), which was calculated by subtracting the bacterial counts at 48 h from the initial inoculum, with a negative value indicating net growth, was also significantly greater . The mean BK48S were -0.69 +/- 0.44 log10 CFU/ml (CI95%, -0.41 to -0.97) and 3.72 +/- 2.28 log10 CFU/ml (CI95%, 2.28 to 5.17) for LY or gentamicin alone versus LY-gentamicin combination regimens, respectively (P < 0.0001) . None of the 12 regimens with LY or gentamicin alone but 75% (9 of 12) of the LY-gentamicin combination regimens were bactericidal . Eighty-three percent (10 of 12) of the LY-gentamicin combination regimens also demonstrated synergy . No significant differences between the pharmacodynamics of LY-gentamicin combination regimens containing Gq24 h versus those containing Gq8h were detected. Antimicrob Agents Chemother, 1999 Mar, 43(3), 483 - 91 Molecular diversity and evolutionary relationships of Tn1546-like elements in enterococci from humans and animals; Willems RJ et al.; We report on a detailed study on the molecular diversity and evolutionary relationships of Tn1546-like elements in vancomycin-resistant enterococci (VRE) from humans and animals . Restriction fragment length polymorphism (RFLP) analysis of the VanA transposon of 97 VRE revealed seven different Tn1546 types . Subsequent sequencing of the complete VanA transposons of 13 VRE isolates representing the seven RFLP types followed by sequencing of the identified polymorphic regions in 84 other VanA transposons resulted in the identification of 22 different Tn1546 derivatives . Differences between the Tn1546 types included point mutations in orf1, vanS, vanA, vanX, and vanY . Moreover, insertions of an IS1216V-IS3-like element in orf1, of IS1251 in the vanS-vanH intergenic region, and of IS1216V in the vanX-vanY intergenic region were found . The presence of insertion sequence elements was often associated with deletions in Tn1546 . Identical Tn1546 types were found among isolates from humans and farm animals in The Netherlands, suggesting the sharing of a common vancomycin resistance gene pool . Application of the genetic analysis of Tn1546 to VRE isolates causing infections in Hospitals in Oxford, United Kingdom, and Chicago, Ill., suggested the possibility of the horizontal transmission of the vancomycin resistance transposon . The genetic diversity in Tn1546 combined with epidemiological data suggest that the DNA polymorphism among Tn1546 variants can successfully be exploited for the tracing of the routes of transmission of vancomycin resistance genes. J Biochem (Tokyo), 1999 Feb, 125(2), 414 - 21 Properties of the V0V1 Na+-ATPase from Enterococcus hirae and its V0 moiety; Murata T et al.; We report here the large-scale purification of vacuolar (V0V1)-type Na+-ATPase from Enterococcus hirae achieved using column anion-exchange and gel filtration chromatographies; 32 mg of purified enzyme comprising nine subunits, A, B, C, D, E, F, G, I, and K, was obtained from 20 liter culture . This amount is 500-fold larger than that reported in the previous paper {Murata, T., Takase, K., Yamato, I., Igarashi, K., and Kakinuma, Y . (1997) J . Biol . Chem . 272, 24885-24890} . The purified enzyme shows a high specific activity of ATP hydrolysis (35.7 micromol Pi released/min/mg protein) . ATP-driven 22Na+ uptake by reconstituted V0V1-proteoliposomes exhibited an apparent Kt value for Na+ of 40 microM, which is near the Km value (20 microM) for Na+ of the ATP hydrolytic activity . Denatured gel electrophoresis revealed that six subunits, A, B, C, D, E, and F, are releasable as the V1 subunit from the V0V1 complex by incubation with ethylenediaminetetraacetic acid; subunit G was not identified . The remaining V0-liposomes containing I and K subunits catalyzed Na+ uptake in response to potassium diffusion potential (Deltapsi, inside negative); the Kt value for Na+ of this reaction was estimated to be about 2 mM . Inhibition by N,N'-dicyclohexylcarbodiimide (DCCD) of the Na+-ATPase activity and Deltapsi-driven Na+ uptake by the V0-liposomes was prevented by the presence of Na+, suggesting that the Na+ binding site overlaps with the DCCD-reactive site. J Clin Microbiol, 1999 Mar, 37(3), 818 - 20 Variation in structure and location of VanA glycopeptide resistance elements among enterococci from a single patient; Tremlett CH et al.; Forty-six VanA glycopeptide-resistant enterococci (GRE) from a single patient were investigated for variation in structure and location of VanA resistance elements . Together with identification to species level and pulsed-field gel electrophoresis, these data divided the GRE into 10 groups and subgroups . Combining data in this manner appears helpful when investigating the epidemiology of GRE. Am J Surg, 1998 Dec, 176(6A Suppl), 67S - 73S Treatment of acute gynecologic infections with trovafloxacin . Trovafloxacin Surgical Group; Roy S et al.; BACKGROUND: Trovafloxacin, a broad-spectrum fourth-generation quinolone with gram-positive and gram-negative aerobic and anaerobic bacterial activity, is available in oral and intravenous formulations . The objective of this prospective, multicenter, double-blind, randomized study was to compare the efficacy of trovafloxacin with that of cefoxitin, an approved drug for treatment of acute gynecologic infections, together with amoxicillin/clavulanic acid as oral follow-on treatment . METHODS: Patients with a clinical diagnosis of acute pelvic infection received either intravenous alatrofloxacin with oral trovafloxacin follow-on (trovafloxacin) or a combined regimen of cefoxitin followed by amoxicillin/clavulanic acid for a maximum of 14 days . The primary endpoint was clinical response to therapy on follow-up at day 30 . RESULTS: Clinical success rates were comparable between the trovafloxacin (n = 107) and comparative (n = 119) groups at study end (90% vs . 86%, respectively; 95% confidence interval, -4.5, 12.5) . Among clinically evaluable patients, clinical success rates for infections involving Enterococcus species were higher with trovafloxacin than with the comparative regimen at the end of treatment (96% and 85%) and at study end (96% and 86%) . CONCLUSION: Intravenous alatrofloxacin followed by oral trovafloxacin for a maximum of 14 days of total therapy was efficacious in the treatment of acute pelvic infections. Infect Control Hosp Epidemiol, 1999 Jan, 20(1), 60 - 3 Vancomycin use in a hospital with vancomycin restriction; Roghmann MC et al.; We evaluated vancomycin use in a hospital with endemic vancomycin-resistant enterococci and a vancomycin restriction program . Only 68% of vancomycin was prescribed appropriately . Inappropriate use was due primarily to empirical therapy . In the patients with a microbiological diagnosis following empirical therapy, 83% (25/30) had infections due to bacteria sensitive to an appropriate antibiotic other than vancomycin . However, only 60% (15/25) of these patients had their vancomycin orders changed. Ann Surg, 1999 Jan, 229(1), 137 - 45 Reconstructive surgery for ischemic-type lesions at the bile duct bifurcation after liver transplantation; Schlitt HJ et al.; OBJECTIVE: To assess the feasibility, morbidity, mortality, and clinical success rate of surgical reconstruction of the biliary system in patients with ischemic-type biliary lesions in their liver graft . SUMMARY BACKGROUND DATA: After liver transplantation, strictures in the biliary tree with secondary sludge formation can occur in the absence of vascular problems . Jaundice, pruritus, and recurrent cholangitis are predominant clinical features leading to considerable morbidity . Interventional measures are the first-line treatment but are frequently only of transient success . Retransplantation is usually considered when interventional treatment is not effective . METHODS: Surgical exploration and reconstruction was performed in 17 patients with ischemic-type biliary strictures at a median of 2 years after liver transplantation . Findings during surgery, surgical strategies, and postsurgical courses are described . Clinical symptoms and biochemical parameters of cholestasis and liver function were analyzed in the postsurgical course . RESULTS: During surgery, all 17 patients were found to have strictures or sclerotic changes involving the hepatic bifurcation and extrahepatic bile duct . Sludge or stones were present in nine patients . In 14 patients with viable bile ducts proximal to the bifurcation, surgical reconstruction was performed by resection of the bifurcation and hepaticojejunostomy . In three patients with more extensive biliary destruction, portoenterostomy with or without peripheral hepatojejunostomy was performed . The prevalence rate of biliary infection at surgery was 93%; the predominant organisms were Candida and enterococci . The perioperative mortality rate was 0% . Clinical symptoms and biochemical parameters became normal or were considerably improved in 14 of 16 patients (88%) . CONCLUSIONS: The hepatic bifurcation seems to be a predominant site for ischemic-type biliary changes after liver transplantation . Surgical treatment by resection of the bifurcation and reconstruction by high hepaticojejunostomy is a safe and highly effective approach leading to cure or persistent major improvement in most patients. Eur J Clin Microbiol Infect Dis, 1998 Nov, 17(11), 798 - 800 Treatment options for chronic prostatitis due to vancomycin-resistant Enterococcus faecium; Taylor SE et al.; Prostatitis due to vancomycin-resistant enterococci has not been previously described . Reported here is a case of chronic prostatitis due to Enterococcus faecium, resistant to vancomycin, ampicillin, ciprofloxacin and doxycycline, in a 42-year-old liver transplant recipient . Treatment with a combination of rifampin and nitrofurantoin for 6 weeks resulted in long-lasting cure . Other antimicrobial agents active in vitro against vancomycin-resistant enterococci, such as quinupristin/ dalfopristin and chloramphenicol, are unlikely to achieve sufficient prostatic tissue levels to be successfully utilized for treatment of this condition. Med Clin (Barc), 1998 Dec 12, 111(20), 761 - 4 {Bacteremia due to vancomycin-resistant enterococci in neutropenic cancer patients}; Marron A et al.; BACKGROUND: The aim of this study was to determine the incidence, clinical characteristics and outcome of vancomycin-resistant enterococcal bacteremia . PATIENTS AND METHODS: We included all cases of enterococcal bacteremia in neutropenic cancer patients documented between January 1986 and December 1995 in a 1,000-bed university hospital, where a prospective surveillance of all cases of bacteremia is regularly done . Molecular typing was performed on all vancomycin-resistant strains with the analysis of chromosomic DNA by macrorestriction . RESULTS: Seventeen cases of enterococcal bacteremia were documented . Seven (41%) were caused by vancomycin-resistant strains (E . faecium 3 and E . gallinarum 4), six of which occurred in the last 5 years of the study period . The average age of patients was 43 years (18-69) and most of them had acute leukemia . Eighty percent of these patients had received vancomycin and/or cephalosporins within 2 weeks prior to bacteremia . Previous administration of antibiotics was more frequent in patients with bacteremia caused by vancomycin-resistant enterococci than in those with bacteremia caused by susceptible strains (86% vs 30%; p < 0.05) . The mean number of previous antibiotics (2.4 vs 0.8; p < 0.05) as well as days of treatment (13.6 vs 4.3; p = 0.05) were also higher among patients with resistant enterococcal bacteremia . The overall mortality was 57% . CONCLUSIONS: This study shows the emergence of sporadic cases of bacteremia caused by vancomycin-resistant enterococci in neutropenic cancer patients in our area . This fact seems to be related with the previous administration of antibiotics and advice that a rational use of these agents is needed. FEMS Microbiol Lett, 1999 Jan 1, 170(1), 25 - 30 Strain typing among enterococci isolated from home-made Pecorino Sardo cheese; Mannu L et al.; Three molecular techniques (RAPD-polymerase chain reaction analysis, plasmid profile and pulsed-field gel electrophoresis) were used for a preliminary approach to type, at strain level, enterococci isolated from a 24-h-old home-made Pecorino Sardo (protected designation of origin) cheese . A high genetic polymorphism was found . Clusters obtained by the RAPD technique and plasmid profile analysis contained different strains . Pulsed-field gel electrophoresis proved to be an efficient and highly reproducible typing method . In addition, by combining the results from plasmid profile analysis and pulsed-field gel electrophoresis, it was possible to identify closely related strains probably belonging to the same clonal lineage. Zentralbl Hyg Umweltmed, 1998 Dec, 201(4-5), 297 - 309 Investigation into the efficacy of disinfectants against MRSA and vancomycin-resistant enterococci; Goroncy-Bermes P; In the study reported here, several disinfectants for surfaces, instruments, hands and mucous membrane were tested for their effectiveness against methicillin-resistant strains of S . aureus and vancomycin-resistant enterococci . The results show that after use of the recommended concentrations with the recommended contact times, which were determined on the basis of the criteria for disinfectants according to the DGHM guideline for the testing and evaluation of chemical disinfection procedures, an adequate effect was able to be proved . Increased resistance of the methicillin-resistant S . aureus and vancomycin-resistant E . faecium strains to the tested disinfectants was not found . Only after use of diluted solutions differences in the bacterial count reductions were observed . In further studies it is to be investigated whether these differences are due to resistance to antibiotics or to intrinsic resistance. J Clin Microbiol, 1999 Feb, 37(2), 413 - 6 Vancomycin-resistant Enterococcus faecium colonization in children; Singh-Naz N et al.; Nosocomial vancomycin-resistant Enterococcus (VRE) infections have been described in only small numbers of pediatric patients . In none of these studies were multivariate analyses performed to assess which factors were independent risk factors in these patients . In the present cohort study of patients admitted to our hematology/oncology unit, surveillance cultures revealed a colonization rate of 24% and all isolates were identified as Enterococcus faecium . Risk factors associated with colonization with VRE identified by multiple logistic regression analysis included young age and chemotherapy with antineoplastic agents, cefotaxime, vancomycin, and ceftazidime . A molecular epidemiological tool, pulsed-field gel electrophoresis, was used to determine the relatedness of the VRE isolates detected . DNA analysis by this method identified two major clusters of VRE isolates . Young children with gastrointestinal colonization with VRE, without evidence of clinical infection, can serve as a reservoir for the spread of VRE. Diagn Microbiol Infect Dis, 1998 Nov, 32(3), 141 - 6 In vitro susceptibility and molecular analysis of gentamicin-resistant enterococci; Chow JW et al.; Enterococci with gentamicin MICs of 256 to 1,024 micrograms/mL were evaluated for susceptibility to ampicillin plus gentamicin synergism . Sixteen of eighteen enterococcal isolates were not susceptible to synergistic killing by ampicillin plus gentamicin; 11 possessed aac(6')-aph(2"), and 4 possessed aph(2")-Ic . A gentamicin MIC of 512 or 1,024 micrograms/mL predicted lack of ampicillin/gentamicin synergism, but a gentamicin MIC of 256 micrograms/mL did not . For six enterococcal strains possessing the gentamicin-resistance gene aph(2")-Ic, ampicillin plus dibekacin, ampicillin plus netilmicin, and ampicillin plus amikacin produced synergistic killing in five, three, and two strains, respectively. FEMS Immunol Med Microbiol, 1998 Dec, 22(4), 283 - 91 A lipoteichoic acid fraction of Enterococcus hirae activates cultured human monocytic cells via a CD14-independent pathway to promote cytokine production, and the activity is inhibited by serum components; Arakaki R et al.; To elucidate the cellular activation mechanisms of lipoteichoic acid (LTA) compared with those of lipopolysaccharide (LPS), a quantitatively major LTA fraction, QM-1M, was prepared from hot phenol-water extracts of Enterococcus hirae (ATCC 9790) by hydrophobic octyl-Sepharose chromatography and by ion-exchange membrane (QMA-Mem Sep 1010) chromatography as a 60% 1-propanol- and 1 M NaCl-eluted fraction . Unlike the reference Escherichia coli LPS, QM-1M did not demonstrate any ability to induce cytokines in a human whole blood culture system in this study, whereas QM-1M induced a few cytokines such as interleukin (IL)-8 and tumor necrosis factor-alpha in human monocytic THP-1 cell and human peripheral mononuclear cell (PBMC) cultures in the absence of serum . Fetal calf and human sera decreased the above cytokine induction by QM-1M in THP-1 and PBMC cultures, whereas sera increased activities of the reference LPS . IL-8 induction in the absence of serum in response to QM-1M was demonstrated to proceed through a CD14-independent pathway unlike the reference LPS. Crit Care Med, 1998 Dec, 26(12), 2001 - 4 External sources of vancomycin-resistant enterococci for intensive care units; Bonten MJ et al.; OBJECTIVE: The incidence of colonization and infection with vancomycin-resistant enterococci (VRE) has increased dramatically in the last 5 yrs, especially in intensive care units (ICUs) . We studied VRE-colonization in patients on admission to a medical ICU (MICU) where VRE colonization is endemic . DESIGN: Prospective, descriptive analysis . SETTING: An MICU of a public hospital . PATIENTS: Three hundred and one consecutively admitted patients . MEASUREMENTS AND MAIN RESULTS: Rectal swabs were obtained on admission from all patients . VRE isolates from all colonized patients were genetically fingerprinted by pulsed-field gel-electrophoresis (PFGE) . Forty-three (14%) of 301 patients were colonized with VRE on MICU admission . Three (7%) of these 43 patients were admitted directly from the community without prior hospital contact . Risk of colonization on admission was related to the length of stay in the hospital before MICU-admission (odds ratio 4.65 for patients with a stay of at least 3 days) and previous in-hospital use of antibiotics . Of 22 VRE PFGE strain types recognized in the MICU during the study period, four (18%) were introduced by patients admitted directly from the community and ten (45%) were introduced by patients admitted from other hospital wards . CONCLUSIONS: These results show that although ICUs are considered epicenters for antibiotic resistance, sources extraneous to our MICU (e.g., other wards) contributed the majority of VRE strain types in the unit. Dis Aquat Organ, 1998 Oct 8, 34(2), 103 - 8 Enterococcus-like infections in Macrobrachium rosenbergii are exacerbated by high pH and temperature but reduced by low salinity; Cheng W et al.; Macrobrachium rosenbergii (10 to 15 g and 8 to 12 g at intermolt) were challenged with an enterococcus-like bacterium (strain KM002) previously isolated and identified as the causal agent of mortality . Challenge doses and conditions of pH, salinity and temperature were varied to determine the influence of environmental factors on the development of disease and mortality . Survival was 100% for the unchallenged control groups in all trials . In pH tests, the onset of mortality was earlier at pH 8.8 to 9.5 than at pH 4.6 to 5.2 and 7.5 to 7.7 . Also, as pH 8.8 to 9.5, all challenged prawns died within 6 d in high dose challenge tests . By contrast, 20% of the prawns challenged at pH 4.6 to 5.2 and 7.5 to 7.7 survived . At low dose challenge (5 x 10(4) cfu prawn(-1)), survival increased significantly except at pH 8.8 to 9.5 . In salinity tests at 2 challenge doses (1 x 10(6) and 2 x 10(7) cfu prawn(-1)), onset of mortality was earliest at 15 ppt and cumulative mortality was 100% at 15 ppt and 0 ppt . By contrast, survival was 80% at 5 and 10 ppt at the low dose challenge and 40% and 60%, respectively, at the high dose challenge . When the challenge dose was reduced to 5 x 10(4) cfu prawn(-1), survival was not significantly different at different salinity levels . In temperature tests at pH 7.2 to 7.5 and at 2 challenge doses (2 x 10(7) and 4 x 10(7) cfu prawn(-1)), the onset of mortality was earliest at 33 to 34 degrees C and total mortality occurred at 27 to 28 degrees C and 33 to 34 degrees C . By contrast, there were 40% and 20% survivors, respectively, for low and high challenge doses at 30 to 31 degrees C . Reducing the challenge dose to 5 x 10(4) cfu prawn(-1) gave higher survival in all groups . However, survival at 33 to 34 degrees C was still lowest . In similar temperature tests but at pH 8.8 to 9.5, onset of mortality was somewhat accelerated and there was 100% death for all the high challenge groups . At low challenge doses, mortality was lower but still highest in the 33 to 34 degrees C group . Results indicated that mortality of M . rosenbergii caused by this Enterococcus-like bacterium was exacerbated by environmental parameters of temperature and pH different from those known to be optimal for prawn growth . By contrast, low salinity appeared to have a beneficial effect on survival . Further work is needed to determine the mechanisms underlying these effects. Arch Surg, 1998 Dec, 133(12), 1343 - 6 Third-generation cephalosporins and vancomycin as risk factors for postoperative vancomycin-resistant enterococcus infection; Dahms RA et al.; OBJECTIVE: To examine use of third-generation cephalosporins (3GCs) alone and in association with vancomycin hydrochloride as a risk factor for vancomycin-resistant enterococcus (VRE) infection in surgical patients . DESIGN: Case-control retrospective study analyzing antibiotic use in the 30 days preceding culture of VRE or vancomycin-sensitive enterococcus from an infected site . SETTING: A large tertiary care teaching hospital . PATIENTS: Surgical inpatients with VRE infections between September 3, 1993, and January 29, 1997, were matched with patients with vancomycin-sensitive enterococcus infections . Matches were based on surgical procedure, initial infection site, and immunosuppression . Matches were found for 32 of 50 surgical patients with VRE . Twenty matched pairs of patients were recipients of solid organ transplants . MAIN OUTCOME MEASURES: Multivariate logistic regression analysis was done to examine 3GCs and vancomycin as risk factors for VRE infection . Univariate analysis of use of other antibiotic agents and demographic data was also performed . RESULTS: Multivariate analysis showed significant differences in the use of 3GCs both alone and concurrently with vancomycin . Univariate analysis also showed higher use of metronidazole, concurrent vancomycin and metronidazole, concurrent vancomycin and ceftazidime, and all antibiotics combined in patients with VRE infections . CONCLUSIONS: This matched control study showed that use of 3GCs, alone (P=.05) or concurrently with vancomycin (P=.05), was a risk factor for VRE infection in surgical patients . Judicious administration of third-generation antibiotics is warranted in surgical patients with other risk factors for VRE. J Investig Med, 1998 Dec, 46(9), 435 - 43 Investigation of an outbreak of vancomycin-resistant Enterococcus faecium in a low prevalence university hospital; Hwang YS et al.; BACKGROUND: Until 1995, there were no cases of vancomycin resistant enterococcus (VRE) identified at our university hospital . From May 1995 to August 1996, we investigated a cluster of 10 cases of phenotypic class Van B Enterococcus faecium . METHODS: Patients were matched with controls who were on the same unit for at least 7 days prior to the case developing VRE . Control patients were age and sex matched if possible, and had duration of hospitalization at least as long as the number of days it took the patient to become VRE positive . We analyzed 16 independent risk factors using Epi-info version 6 . Environmental cultures were obtained in the MICU where 5 of the patients were located . All 10 patient isolates and environmental isolates were analyzed by pulsed field gel electrophoresis (PFGE) . RESULTS: PFGE confirmed the genetic relatedness of all 10 patient isolates and environmental isolates . The VRE-positive group was more likely to be immunosuppressed and to have exposure to 3 physicians . In the MICU, significant, P < 0.05) risk factors for VRE were higher Apache scores, location adjacent to a VRE case, duration of vancomycin and amino-glycoside use, duration of invasive catheter use, and diarrhea . Among the VRE-positive environmental cultures was a blood pressure cuff wash that was used on several patients . CONCLUSION: We hypothesize that a VRE strain was introduced into our hospital environment and was spread by personnel or contaminated equipment . As a consequence of this study, a hospital-wide VRE policy was implemented. Am J Gastroenterol, 1998 Dec, 93(12), 2491 - 500 Prospective case-cohort study of intestinal colonization with enterococci that produce extracellular superoxide and the risk for colorectal adenomas or cancer; Winters MD et al.; OBJECTIVE: The aim of this study was to determine whether intestinal colonization with enterococci that produce extracellular superoxide (O2*-), a free radical implicated in the development of colorectal cancer, is associated with these lesions or their precursors . METHODS: A prospective case-cohort study was performed by isolating enterococci from stools of consecutive patients undergoing colonoscopy who had no prior history of colonoscopy or colorectal cancer . A food frequency questionnaire was also administered to control for dietary factors known to affect the risk for these lesions . RESULTS: Among 159 evaluable participants were 77 with no precancerous or cancerous pathology, 61 with adenomas <2 cm, 10 with adenomas > or =2 cm, and 11 with cancer . Regression analyses found no associations for those subjects with adenomas of any size or with cancer and colonization with O2*--producing enterococci, any nutrient, or age . For those patients with large adenomas > or = 2 cm or cancer, however, significant associations were noted for age (OR 1.94 per decade, 95% CI 1.2-3.5), beta-carotene (OR 0.44 per 500 microg/1000 kcal/day, 95% CI 0.2-0.8), vitamin A (OR 3.20 per 500 microg/1000 kcal/day, 95% CI 1.2-8.9), and vitamin E (OR 0.09 per 10 mg/ 1000 kcal/day, 95% CI 0.006-0.9), but not colonization with O2*--producing enterococci . Second stools collected 1 yr later, however, often contained dissimilar enterococcal flora, undermining an important study assumption . CONCLUSIONS: Significant associations were found for those with large adenomas or cancer (but not small adenomas), with age, and with foods enriched for vitamin A, vitamin E, and beta-carotene . An association between colonization with O2*--producing enterococci and colorectal adenomas or cancer, however, could not be ascertained, possibly because intestinal enterococcal flora changes over time, leaving a potentially cohesive hypothesis of colon cancer and risk factors as yet unanswered. J Antimicrob Chemother, 1998 Nov, 42(5), 605 - 12 Molecular analysis of diverse elements mediating VanA glycopeptide resistance in enterococci; Palepou MF et al.; Differences were examined among 24 distinct elements mediating VanA-type glycopeptide resistance in enterococci isolated from hospital patients and non-human sources in the UK . The methods used included long-PCR restriction fragment length polymorphism (L-PCR RFLP) analysis and DNA hybridization . All elements had conserved vanRSHAX genes, but variation occurred upstream of vanR and downstream of vanX . Twenty-one VanA elements had significant alterations upstream of vanR in the transposition genes orf1 and orf2: either parts of these genes were absent or they were disrupted by IS1216V or IS3-like insertion sequences . Among VanA elements with alterations downstream of vanX, seven lacked vanY, one lacked both vanY and vanZ, and ten had copies of insertion sequence IS1216V between vanX and vanY . All VanA elements of group D (from geographically and temporally diverse enterococci) were characterized by the presence of an IS1216V/IS3-like/orf1 complex and a point mutation in vanX, both of which were absent from the other 23 groups of VanA elements . This finding is consistent with the dissemination of a stable resistance element . We conclude that L-PCR RFLP analysis, combined with DNA hybridization, merits further development for studying the evolution and epidemiology of VanA resistance elements in enterococci. Tidsskr Nor Laegeforen, 1998 Oct 30, 118(26), 4070 - 3 {Infections caused by multiresistant enterococci in Norway}; Harthug S et al.; During the last decade antimicrobial resistant pathogens have become a major medical problem . Internationally, multiresistant enterococci have increased nosocomial morbidity and mortality . Such strains are often resistant to ampicillin, aminoglycosides, and glycopeptides such as vancomycin . The spread of these strains has been shown to correlate to the use of antibiotics and the practice of suboptimal infection control within health care facilities . The current situation in Norwegian hospitals is presented, including the only six cases with infections and the three carriers of vancomycin resistant enterococci found to date . Surveillance in the hospitals shows that such strains are uncommon in non-infected patients . To maintain this favourable situation it is necessary to continue to practice effective methods of infection control and to employ sound antibiotic policies. J Infect Dis, 1999 Jan, 179(1), 163 - 71 The changing molecular epidemiology and establishment of endemicity of vancomycin resistance in enterococci at one hospital over a 6-year period; Kim WJ et al.; The contributions of clonal spread, transfer of genetic elements, and introduction of new strains to the establishment of endemicity of vancomycin-resistant enterococci (VRE) were determined . The study took place at one hospital between 1990, when VRE were first detected, and 1996, when endemicity had become established . Isolates from 183 patients were categorized into 24 strain types by pulsed-field gel electrophoresis; the resistance genotype was determined by polymerase chain reaction . Between 1990 and 1993, 69% of patients were infected with the same vanB Enterococcus faecium strain . VanA resistance was not detected until 1993, but in 1996, the ratio of vanA to vanB was 2.2:1 . Over time, 8 vanA strains were detected; a 35- or 40-kb conjugative vanA plasmid was found in 4 of the 8 strains . Clonal spread was a major factor in the establishment of endemicity . Transfer of genetic elements and introduction of new strain types were detected less often . However, these events may have been equally important evolutionarily. Am J Infect Control, 1998 Dec, 26(6), 569 - 71 Detection of vancomycin-resistant enterococci colonization in a children's hospital; Christenson JC et al.; BACKGROUND: Vancomycin-resistant enterococci (VRE) are important nosocomial pathogens in many hospitals . The true prevalence of VRE in pediatric hospitals is not known . METHODS: A surveillance study was performed at a pediatric tertiary care medical center by using vancomycin-containing screening media . RESULTS: Six children (of 112 screened) were found to be colonized with VRE . Colonized patients had a history of receiving broad-spectrum antimicrobial agents . CONCLUSION: In the absence of VRE infections, surveillance studies can help determine the extent of VRE colonization and support infection control measures. Antimicrob Agents Chemother, 1998 Dec, 42(12), 3279 - 81 In vitro activity of the new ketolide HMR3647 in comparison with those of macrolides and pristinamycins against Enterococcus spp; Torres C et al.; Ninety-four erythromycin-susceptible and 107 erythromycin-resistant enterococcal strains (MIC of >/=512 microgram/ml) were inhibited by the ketolide HMR3647 at MICs of </=0.007 to 0.06 and 0.03 to 8 microgram/ml, respectively . Eighteen vanA-positive isolates and 29 high-level-penicillin-resistant isolates, all of them erythromycin resistant, were inhibited by HMR3647 at an MIC range of 0.015 to 4 microgram/ml . The new ketolide has excellent activity against Enterococcus species. J Hosp Infect, 1998 Nov, 40(3), 237 - 41 The toilet as a transmission vector of vancomycin-resistant enterococci; Noble MA et al.; An elderly woman, admitted to the intensive care unit of a large university teaching hospital, was found to be colonized with vancomycin-resistant enterococci leading to the temporary closure of the unit . She had acquired the organism nosocomially, most likely from an environmental source, which had been contaminated when the toilet of a former patient, also colonized with vancomycin-resistant enterococci, had become blocked and overflowed throughout his and the adjoining room . This is the first report of a hospital toilet as the transmission vector for vancomycin-resistant enterococci. Mem Inst Oswaldo Cruz, 1998 Sep-Oct, 93(5), 587 - 8 Vancomycin-resistant enterococci in intensive care hospital settings; Austin DJ et al.; Vancomycin-resistant enterococci (VRE) have recently emerged as a nosocomial pathogen and present an increasing threat to the treatment of severely ill patients in intensive-care hospital settings . We outline results of a study of the epidemiology of VRE transmission in ICUs and define a reproductive number R0; the number of secondary colonization cases induced by a single VRE-colonized patient in a VRE-free ICU, for VRE transmission . For VRE to become endemic requires R0 > 1 . We estimate that in the absence of infection control measures R0 lies in the range 3-4 in defined ICU settings . Once infection control measures are included R0 = 0.6, suggesting that admission of VRE-colonized patients can stabilize endemic VRE. J Food Prot, 1998 Nov, 61(11), 1454 - 8 Growth and adherence on stainless steel by Enterococcus faecium cells; Andrade NJ et al.; Enterococcus faecium isolated from Brazilian raw milk was used in this study . For growth studies, E . faecium was inoculated into 10% RSM (reconstituted skim milk) and MRS both, incubated at 6.5 and 9 degrees C for 10 days and at 30, 42, and 45 degrees C for 48 h . Cells were enumerated after spread-plating onto MRS agar and incubating at 30 degrees C for 48 h . The ability of E . faecium cells to adhere to stainless-steel chips (6 by 6 by 1 mm, AISI 304, finish #4) was investigated . MRS broth containing stainless steel chips was inoculated to an initial concentration of 10(3) or 10(6) CFU/ml of E . faecium . Adherent cells were stained with acridine orange and enumerated by epifluorescence microscopy . E . faecium grew between 6.5 and 42 degrees C in MRS and between 9 and 40 degrees C in RSM . In MRS broth with 10(6) or 10(3) CFU/ml, the g (generation time) values were 0.62 and 0.42 h and R (growth rate) values were 1.6 and 2.4 h-1 . Values of R = 2.3 h-1 and g = 0.43 h were determined for E . faecium growing in RSM with 10(3) CFU/ml . In MRS broth, for samples with a starting concentration of 10(6) cells per ml, adherence to stainless-steel chips was first observed at 2 h . However, adherence was first observed at 4 h in samples with an initial concentration of 10(3) cells per ml . After 10 h of exposure the number of adherent cells was similar for all samples regardless of initial inoculum . These results indicate that E . faecium readily adheres to stainless steel . It also underscores the need to control E . faecium by using appropriate low storage temperatures and adequate sanitizing practices in the dairy industry. Clin Infect Dis, 1998 Nov, 27(5), 1259 - 65 The role of chloramphenicol in the treatment of bloodstream infection due to vancomycin-resistant Enterococcus; Lautenbach E et al.; The incidence of bacteremia due to vancomycin-resistant Enterococcus (VRE) has increased markedly in recent years . We investigated the role of chloramphenicol in its treatment . All cases of VRE bacteremia occurring at our facility during a 45-month period were analyzed . The response to chloramphenicol, its effect on mortality, and the incidence of adverse effects were assessed . Fifty-one patients (65.4%) received chloramphenicol . Among patients in whom a response could be assessed, 22 (61.1%) of 36 demonstrated a clinical response, while 34 (79.1%) of 43 showed a microbiological response . Forty-two patients (53.8%) died as a result of the bacteremia . Although the mortality rate was lower for patients treated with chloramphenicol, the difference was not significant (odds ratio = 0.72; 95% confidence interval, 0.28-1.85; P = .49), nor was there an association between earlier initiation of therapy and reduced mortality (P = .45) . In cases with central line-related bacteremia, there was no difference in mortality among patients treated with chloramphenicol, line removal, or both (P = .36) . Although 16 patients (31.4%) had adverse effects, none could be definitely attributed to chloramphenicol . Although chloramphenicol was well-tolerated, no significant effect of its use on mortality could be demonstrated. Infect Immun, 1998 Dec, 66(12), 6022 - 3 Correlation of cecal microflora of HLA-B27 transgenic rats with inflammatory bowel disease; Onderdonk AB et al.; Transgenic rats with a high level of expression of the human major histocompatibility complex class I molecule HLA-B27 develop chronic inflammatory bowel disease (IBD) and arthritis . Assessment of the cecal microflora showed a rise in numbers of Escherichia coli and Enterococcus spp., corresponding to the presence and severity of IBD in these rats. J Am Med Inform Assoc, 1998 Nov-Dec, 5(6), 554 - 62 Reducing vancomycin use utilizing a computer guideline: results of a randomized controlled trial; Shojania KG et al.; BACKGROUND: Vancomycin-resistant enterococci represent an increasingly important cause of nosocomial infections . Minimizing vancomycin use represents a key strategy in preventing the spread of these infections . OBJECTIVE: To determine whether a structured ordering intervention using computerized physician order entry that requires use of a guideline could reduce intravenous vancomycin use . DESIGN: Randomized controlled trial assessing frequency and duration of vancomycin therapy by physicians . PARTICIPANTS AND SETTING: Three hundred ninety-six physicians and 1,798 patients in a tertiary-care teaching hospital . INTERVENTION: Computer screen displaying, at the time of physician order entry, an adaptation of the Centers for Disease Control and Prevention guidelines for appropriate vancomycin use . MAIN OUTCOME MEASURES: The frequency of initiation and renewal of vancomycin therapy as well the duration of therapy prescribed on a per prescriber basis . RESULTS: Compared with the control group, intervention physicians wrote 32 percent fewer orders (11.3 versus 16.7 orders per physician; P = 0.04) and had 28 percent fewer patients for whom they either initiated or renewed an order for vancomycin (7.4 versus 10.3 orders per physician; P = 0.02) . In addition, the duration of vancomycin therapy attributable to physicians in the intervention group was 36 percent lower than the duration of therapy prescribed by control physicians (26.5 versus 41.2 days; P = 0.05) . Analysis of pharmacy data confirmed a decrease in the overall hospital use of intravenous vancomycin during the study period . CONCLUSION: Implementation of a computerized guideline using physician order entry decreased vancomycin use . Computerized guidelines represent a promising tool for changing prescribing practices. Diagn Microbiol Infect Dis, 1998 Oct, 32(2), 95 - 9 In vitro activity of RPR 106972 alone and in combination with vancomycin, ampicillin, and gentamicin against multidrug-resistant enterococci; Messick CR et al.; This investigation used checkerboard and time-kill assays to evaluate the in vitro activity of RPR 106972 (45% pristinamycin IB and 55% pristinamycin IIB) alone and in combination with vancomycin or ampicillin +/- gentamicin against multidrug-resistant enterococci . The checkerboard procedure resulted in synergistic or additive effects in 91% of the isolates with the combination of RPR 106972 plus vancomycin versus 68% with RPR 106972 plus ampicillin . The addition of gentamicin to either combination resulted in synergistic or additive results in 100% of the isolates . Inhibitory activity was observed with the time-kill assay with mean change in log10 CFU/mL at 24 h of -0.31 for RPR 106972, 3.3 for vancomycin, -0.46 for RPR 106972 plus vancomycin, and -0.35 for RPR 106972 plus vancomycin and gentamicin . No antagonism was noted with any of the combinations . RPR 106972 demonstrates good inhibitory activity against Enterococcus faecium and may prove useful in the treatment of enterococcal infections. Int Endod J, 1998 Jan, 31(1), 1 - 7 Microbiological status of root-filled teeth with apical periodontitis; Molander A et al.; The present study examined the microbiological status of 100 root-filled teeth with radiographically verified apical periodontitis--the pathology (P) group--and of 20 teeth without signs of periapical pathosis--the technical (T) group . In the P group 117 strains of bacteria were recovered in 68 teeth . In most of the cases examined one or two strains were found . Facultative anaerobic species predominated among these isolates (69% of identified strains) . Growth was classified as 'sparse' or 'very sparse' in 53%, and as 'heavy' or 'very heavy' in 42% . Enterococci were the most frequently isolated genera, showing 'heavy' or 'very heavy' growth in 25 out of 32 cases (78%) . In 11 teeth of the T group no bacteria were recovered, whilst the remaining nine yielded 13 microbial strains . Eight of these grew 'very sparsely' . It is concluded that the microflora of the obturated canal differs from that found normally in the untreated necrotic dental pulp, quantitatively as well as qualitatively . Nonsurgical retreatment strategies should be reconsidered. J Infect, 1998 May, 36(3), 324 - 7 RP59500 (Quinupristin/dalfopristin): three case reports of its use in infection due to Enterococcus faecium; Cassell J et al.; We describe three cases of Enterococcus faecium sepsis arising in immunocompromised patients, severely ill with other conditions, who were treated with the new injectable streptogramin RP59500 . There are still few reports of clinical experience with this drug . All had bacteriological resolution, with one patient recovering fully . Although two of the three patients died, this was due to underlying disease in one case and a gram-negative superinfection in another . Quinupristin/dalfopristin therapy was not associated with significant adverse effects in any of the patients. FEMS Microbiol Lett, 1998 Nov 1, 168(1), 145 - 51 Detection of the satA gene and transferability of virginiamycin resistance in Enterococcus faecium from food-animals; Hammerum AM et al.; The satA gene encoding streptogramin A resistance was detected in virginiamycin-resistant Enterococcus faecium isolates from pigs and broilers . The satA gene was present in 22 of 89 (25%) virginiamycin-resistant E . faecium isolates . It was shown that the satA gene and other gene(s) encoding streptogramin resistance could be transferred between isogenic E . faecium strains at frequencies ranging from 2.3 x 10(-4) to 2.2 x 10(-3) transconjugants per donor. Eur J Clin Microbiol Infect Dis, 1998 Aug, 17(8), 576 - 7 Enterococcus hirae septicemia in a patient with end-stage renal disease undergoing hemodialysis; Gilad J et al.; Enterococcus hirae, member of the Enterococcus genus known to cause infection in animals, is rarely encountered in clinical practice . There are no published reports describing clinical features of Enterococcus hirae infection in humans . A case of Enterococcus hirae septicemia in a 49-year-old patient with end-stage renal disease undergoing hemodialysis is reported here . A review of the available literature regarding the clinical spectrum of Enterococcus hirae infection in humans and the antimicrobial susceptibility of Enterococcus hirae is also included. Presse Med, 1998 Sep 26, 27(28), 1427 - 9 {Vancomycin resistant enterococcus in France . High prevalence in a young ambulatory care patient population}; Guerin F et al.; OBJECTIVE: Assess the prevalence of asymptomatic carriage of vancomycin-resistant Enterococci in a population of healthy young French subjects . METHODS: Stool samples obtained from 100 persons living in south-eastern France (20 sampling sites) were directly seeded on enriched selective media containing 6 mg/l vancomycin . Bacterial species and their resistant gene were identified with classical methods and multiplex genomic amplification . RESULTS: The incidence of asymptomatic carriage was 17% with a homogeneous geographic distribution of the resistant strains . Nine Enterococcus faecium van A strains and 8 E . gallinarum van C1 strains were isolated . CONCLUSION: These findings demonstrate carriage of vancomycin-resistant Enterococci in a population of young ambulatory subjects in France . The incidence observed was much higher than in an earlier study conducted in France . These results might be explained by a much more sensitive detection technique . Care should be taken to avoid dissemination in hospital settings. ANNA J, 1998 Aug, 25(4), 381 - 6; quiz 387-8 Vancomycin resistant enterococcus in a hospital-based dialysis unit; Korff A et al.; OBJECTIVE: The emergence of vancomycin resistant enterococcus (VRE) poses a serious threat to the health care community . Reservoirs of VRE are thought to exist in certain high-risk patient groups who reintroduce the organism into the hospital environment . The frequent use of vancomycin in dialysis patients may place this population at higher risk of developing VRE . This article describes the development of VRE and a point prevalence study conducted in a hospital-based dialysis unit . SETTING/SAMPLE: A dialysis unit of a tertiary care center in the eastern United States was selected as the study site . Patients who agreed to participate in the study after giving informed consent were included . Of the 85 members of this target population 33 (38.8%) agreed to participate in the study . The duration of the study was 30 days . DESIGN: After the literature was reviewed, a point prevalence study was completed at the study site . Stool samples or rectal swabs were collected from the study participants and analyzed for the presence of VRE . A chart review of patient demographic and prior treatment information was completed in order to help identify factors that correlate to the presence of VRE . METHODS: Stool or rectal swab samples were cultured on selective media and sensitivity to vancomycin was measured . RESULTS: A 9.1% prevalence of VRE was detected within the study group . The number of VRE positive subjects (3) did not allow statistically significant correlation with the demographic and prior treatment data collected . CONCLUSION: Although VRE remains a serious threat to the health care community, the prevalence of VRE within the study group does not vary markedly from rates previously reported. J Bacteriol, 1998 Nov, 180(21), 5792 - 5 DdlN from vancomycin-producing Amycolatopsis orientalis C329.2 is a VanA homologue with D-alanyl-D-lactate ligase activity; Marshall CG et al.; Vancomycin-resistant enterococci acquire high-level resistance to glycopeptide antibiotics through the synthesis of peptidoglycan terminating in D-alanyl-D-lactate . A key enzyme in this process is a D-alanyl-D-alanine ligase homologue, VanA or VanB, which preferentially catalyzes the synthesis of the depsipeptide D-alanyl-D-lactate . We report the overexpression, purification, and enzymatic characterization of DdlN, a VanA and VanB homologue encoded by a gene of the vancomycin-producing organism Amycolatopsis orientalis C329.2 . Evaluation of kinetic parameters for the synthesis of peptides and depsipeptides revealed a close relationship between VanA and DdlN in that depsipeptide formation was kinetically preferred at physiologic pH; however, the DdlN enzyme demonstrated a narrower substrate specificity and commensurately increased affinity for D-lactate in the C-terminal position over VanA . The results of these functional experiments also reinforce the results of previous studies that demonstrated that glycopeptide resistance enzymes from glycopeptide-producing bacteria are potential sources of resistance enzymes in clinically relevant bacteria. J Med Microbiol, 1998 Oct, 47(10), 849 - 62 Glycopeptide-resistant enterococci: a decade of experience; Woodford N; Since their first description in 1988, glycopeptide-resistant enterococci (GRE) have emerged as a significant cause of nosocomial infections and colonisations, particularly in Europe and the USA . Two major genetically distinct forms of acquired resistance, designated VanA and VanB, are recognised, although intrinsic resistance occurs in some enterococcal species (VanC) and a third form of acquired resistance (VanD) has been reported recently . The biochemical basis of each resistance mechanism is similar; the resistant enterococci produce modified peptidoglycan precursors that show decreased binding affinity for glycopeptide antibiotics . Although VanA resistance is detected readily in the clinical laboratory, the variable levels of vancomycin resistance associated with the other phenotypes makes detection less reliable . Under-reporting of VanB resistance as a result of a lower detection rate may account, in part, for the difference in the numbers of enterococci displaying VanA and VanB resistance referred to the PHLS Laboratory of Hospital Infection . Since 1987, GRE have been referred from >1100 patients in almost 100 hospitals, but 88% of these isolates displayed the VanA phenotype . It is possible that, in addition to the problems of detection, there may be a real difference in the prevalence of VanA and VanB resistance reflecting different epidemiologies . Our present understanding of the genetic and biochemical basis of these acquired forms of glycopeptide resistance has been gained mainly in the last 5 years . However, these relatively new enterococcal resistances appear still to be evolving; there have now been reports of transferable VanB resistance associated with either large chromosomally borne transposons or plasmids, genetic linkage of glycopeptide resistance and genes conferring high-level resistance to aminoglycoside antibiotics, epidemic strains of glycopeptide-resistant Enterococcus faecium isolated from multiple patients in numerous hospitals, and of glycopeptide dependence (mutant enterococci that actually require these agents for growth) . The gene clusters responsible for VanA and VanB resistance are located on transposable elements, and both transposition and plasmid transfer have resulted in the dissemination of these resistance genes into diverse strains of several species of enterococci . Despite extensive research, knowledge of the origins of these resistances remains poor . There is little homology between the resistance genes and DNA from either intrinsically resistant gram-positive genera or from the soil bacteria that produce glycopeptides, which argues against direct transfer to enterococci from these sources . However, recent data suggest a more distant, evolutionary relationship with genes found in glycopeptide-producing bacteria . In Europe, VanA resistance occurs in enterococci isolated in the community, from sewage, animal faeces and raw meat . This reservoir suggests that VanA may not have evolved in hospitals, and its existence has been attributed, controversially, to use of the glycopeptide avoparcin as a growth promoter, especially in pigs and poultry . However, as avoparcin has never been licensed for use in the USA and, to date, VanB resistance has not been confirmed in non-human enterococci, it is clear that the epidemiology of acquired glycopeptide resistance in enterococci is complex, with many factors contributing to its evolution and global dissemination. Syst Appl Microbiol, 1998 Aug, 21(3), 450 - 3 Application of 23S rDNA-targeted oligonucleotide probes specific for enterococci to water hygiene control; Frahm E et al.; Identification of enterococci species by hybridization with recently designed species-specific and group-specific 23S rDNA-targeted oligonucleotide probes was superior to results obtained with a common biochemical test panel . Considering these findings, a molecular biological procedure for the detection of enterococci in water samples was developed . A short enrichment is followed by an amplification step and a hybridization reaction in microtiter plate format . The detection limit is about 1 CFU/ml, and results are available within 26 h. Infect Control Hosp Epidemiol, 1998 Sep, 19(9), 647 - 52 Failure to eradicate vancomycin-resistant enterococci in a university hospital and the cost of barrier precautions; Lai KK et al.; OBJECTIVE: To describe the effect of infection control interventions on the incidence of vancomycin-resistant enterococci (VRE), the utility of pharyngeal cultures for surveillance for VRE colonization, and the cost of barrier precautions . DESIGN: Evaluation of the occurrence of VRE infection or colonization, rates of vancomycin use, results of surveillance cultures before and after interventions, and the cost of increased barrier precautions . SETTING: University of Massachusetts Medical Center, a 347-bed tertiary-care teaching hospital with eight intensive-care units, one burn unit, and one bone marrow transplant unit . PARTICIPANTS: Patients in the intensive-care units and staff who were involved with patients colonized or infected with VRE . METHODS: Infection control interventions included placement of patients with VRE in private rooms, strict contact isolation, cohorting of patient and nursing staff, prohibiting of equipment sharing, and monitoring of compliance with the vancomycin restriction policy, with hand washing, and of the adequacy of environmental cleaning . Both rectal and pharyngeal cultures were obtained from patients at the beginning of the outbreak, and the utility of pharyngeal cultures was evaluated . The cost of barrier precautions was estimated by comparing the cost of glove and gown use before and after the outbreak began . RESULTS: The interventions decreased the number of new cases of VRE, but total eradication of VRE was not achieved . Compliance with the room-cleaning protocol was 91% (141/155 observations) . Hand washing following interaction with patients who were not in isolation was 51%, vs 100% for patients in isolation . Overall, handwashing compliance was 71% (319/449): 56% (130/231) for physicians and 86% (187/218) for nurses (P<.0001) . The mean number of doses of vancomycin dispensed per 1,000 patient days decreased from 145 to 114 per 1,000 patient days (P<.001) . Compliance with vancomycin-use guidelines was 85% . Forty-six (77%) of 60 surveillance rectal swabs yielded enterococci, as compared to only 4 (11%) of 36 pharyngeal cultures (P<.0001) . Expenses on glove and gowns alone increased by over $11,000 per year since the epidemic began . CONCLUSIONS: Implementation of the various infection control measures did not eradicate VRE cases from the hospital . Rectal cultures were more useful than pharyngeal cultures for surveillance of VRE . Controlling VRE epidemics can be costly. J Clin Microbiol, 1998 Nov, 36(11), 3327 - 31 Comparison of genomic methods for differentiating strains of Enterococcus faecium: assessment using clinical epidemiologic data; Savor C et al.; Genomic DNA extracted from 45 vancomycin-resistant Enterococcus faecium (VRE) isolates was cleaved with HindIII and HaeIII and subjected to agarose gel electrophoresis . The ability of this method (restriction endonuclease analysis {REA}) to distinguish strains at the subspecies level was compared with results previously determined by pulsed-field gel electrophoresis (PFGE) . Chart reviews were performed to provide a clinical correlation of possible epidemiologic relatedness . A likely clinical association was found for 29 patients as part of two outbreaks . REA found 21 of 21 isolates were the same type in the first outbreak, with PFGE calling 19 strains the same type . In the second outbreak with eight patient isolates, HindIII found six were the same type and two were unique types . HaeIII found three strains were the same type, two strains were a separate type, and three more strains were unique types, while PFGE found three were the same type and five were unique types . No single "ideal" method can be used without clinical epidemiologic investigation, but any of these techniques is helpful in providing focus to infection control practitioners assessing possible outbreaks of nosocomial infection. J Clin Microbiol, 1998 Nov, 36(11), 3303 - 8 Molecular analysis of glycopeptide-resistant Enterococcus faecium isolates collected from Michigan hospitals over a 6-year period; Thal L et al.; The purpose of this study was to evaluate the molecular relatedness of clinical isolates of glycopeptide-resistant Enterococcus faecium isolates collected from hospitals in Michigan . A total of 379 isolates used in this study were all vancomycin-resistant E . faecium isolates collected from 28 hospitals and three extended-care facilities over a 6-year period from 1991 to 1996 . For the 379 isolates, there were 73 pulsed-field gel electrophoresis (PFGE) strain types . Within strain types, there were as many as six restriction fragment differences . Most isolates (70%) belonged to six strain types, which were designated M1 (36%), M2 (3%), M3 (18%), M4 (6%), M10 (4%), and M11 (3%) . PFGE strain M1 was cultured from 135 patients in 13 hospitals during the period 1993 to 1996 . Strain type M2 was cultured from 11 patients in two hospitals during the period 1991 to 1992 and was not observed after 1992 . Strain type M3 was cultured from 70 patients in 10 hospitals during the period of 1994 to 1996 . Both M4 and M10 were cultured from 23 patients in three hospitals and from 15 patients in two hospitals, respectively, during 1995 to 1996 . M11 was cultured from 13 patients in four hospitals during 1996 . A total of 23 of 28 hospitals had evidence of clonal dissemination of some isolates . Plasmid content and hybridization analysis done on 103 isolates from one hospital and two affiliated extended-care facilities indicated that the strains contained from one to eight plasmids . Mating experiments indicated transfer of vancomycin resistance from 94 of these isolates into plasmid-free E . faecium GE-1 at transfer frequencies of <10(-9) to 10(-4) . Gentamicin resistance and erythromycin resistance were cotransferred at various frequencies . A probe for the vanA gene hybridized to the plasmids of 23 isolates and to the chromosomes of 72 isolates . A probe for the vanB gene hybridized to the chromosomes of 8 isolates . The results of this study suggest inter- and intrahospital dissemination of vancomycin-resistant E . faecium strains over a 6-year period in southeastern Michigan . The majority of isolates studied belonged to the same few PFGE strains, indicating that clonal dissemination was responsible for most of the spread of resistance that occurred. Zhonghua Yi Xue Za Zhi, 1997 May, 77(5), 327 - 31 {Trends and changes in antimicrobial resistance of clinical isolates from 11 hospitals in Beijing area}; Zhang F et al.; OBJECTIVE: To study the antimicrobial resistance and its changes of clinical isolates in Beijing area . METHODS: The diameters of the inhibition zones of clinical isolates around antibiotic susceptibility test discs at 12 hospitals in Beijing area were computerfiled and analysed by the software of 'WHONET' according to NCCLS published in 1994 . RESULTS: A total of 10,305 isolates were collected in 1995 . The percentages of resistance were as follows: (1) in E . coli: amikacin, 8%, ceftazidime, 15%, the other third generation cephalosporins, about 30%, (2) in Klebsiella spp: ofloxacin, 0%, ceftazidime, 15%, ciprofloxacin, 17%, norfloxacin, 15%, ofloxacin, 5%, (4) in Staph . aureus: norvancomycin, 0%, (5) in Strep . pneumoniae: penicillin G, 9%, (6) in Enterococcus spp: norvancomycin, 7% . The antimicrobial resistant changes over a six year period from 1990 to 1995 were surveyed and it was found that resistant percentage of the most isolates to quinolones, for example norfloxacin, increased significantly year by year and no remarkable differences of resistance to antimicrobial agents but quinolones were observed in Ps . aeruginosa . CONCLUSION: Antimicrobial resistance should be emphasised during clinical therapy with antimicrobial agents, and trends in antimicrobial resistance of isolates should be followed. J Natl Med Assoc, 1998 Sep, 90(9), 537 - 40 Multidrug-resistant enterococci: the dawn of a new era in resistant pathogens; Antony SJ; Resistant enterococci, especially vancomycin-resistant enterococci, have rapidly become an important nosocomial pathogen . They are increasingly prevalent among hospitalized patients, patients with serious chronic illnesses, and immunosuppressed patients . Risk factors identified include previous antibiotics, exposure to contaminated equipment, and close proximity to infected patients . Treatment of multidrug-resistant pathogens has become increasingly difficult, with increased morbidity and mortality in these patients . Strict infection control measures remain the mainstay in the management of these infections. FEMS Microbiol Lett, 1998 Sep 15, 166(2), 355 - 60 The PBP 5 synthesis repressor (psr) gene of Enterococcus hirae ATCC 9790 is substantially longer than previously reported; Massidda O et al.; A reexamination of the nucleotide sequence of the psr gene of Enterococcus hirae revealed the presence of two additional nucleotides at residues 1190 and 1191 . As a result, instead of a stop codon after 148 aa, the psr gene product would contain 293 aa residues . The revised size of the gene product was confirmed by subsequently cloning and expressing the psr gene in Escherichia coli . The derived amino acid sequence of the revised psr gene product was found to be similar to several other proteins in the combined GenBank/EMBL database . The protein products of some of these genes are thought to play regulatory role(s) in exo or capsular polysaccharide synthesis and/or in cell wall metabolism . All the putative homologs of the revised Psr appear to have a putative membrane-anchoring domain at their N-termini . Amino acid blocks with high degrees of similarity have been identified in the aligned sequences, and it is suggested that these common motifs could be of structural or functional importance. Diagn Microbiol Infect Dis, 1998 Aug, 31(4), 525 - 30 Colonization and microbiology of the motile enterococci in a patient population; Van Horn KG et al.; The motile enterococci with the vanC gene have intrinsic low-level resistance to vancomycin, but have not been implicated in a nosocomial outbreak . We determined the colonization rate of motile enterococci in hospitalized and nonhospitalized patients . Perianal or stool specimens were cultured in Enterococcosel broth supplemented with 6 micrograms of vancomycin per mL . Rapid motility and pigment tests were performed on all enterococci isolated . A total of 82 motile and/or pigmented enterococci were isolated from 679 patients for a colonization rate of 12.1% . There were 43 Enterococcus gallinarum, 32 Enterococcus casseliflavus, 4 Enterococcus flavescens, and 3 Enterococcus mundtii identified . The E . gallinarum vancomycin MIC90 was 32 micrograms/mL and the E . casseliflavus vancomycin MIC90 was 8 micrograms/mL. Infect Control Hosp Epidemiol, 1998 Aug, 19(8), 546 - 51 Spread of vancomycin-resistant enterococci: differences between the United States and Europe; Goossens H; There are major differences in the epidemiology of vancomycin-resistant enterococci (VRE) between the United States and Europe . In contrast with Europe, VRE in the United States are resistant to many antibiotics, and there appears to be less genetic variability among these isolates . European VRE of human origin are usually susceptible to many other antibiotics and are highly polyclonal . These clinical isolates have the same susceptibility profiles as VRE isolated from animals . The differences in the spread of VRE between the United States and Europe might be explained by the overconsumption of glycopeptides and other antibiotics in hospitals in the United States and the use of avoparcin as a growth promotor in Europe. Antimicrob Agents Chemother, 1998 Oct, 42(10), 2710 - 7 Treatment of vancomycin-resistant Enterococcus faecium with RP 59500 (quinupristin-dalfopristin) administered by intermittent or continuous infusion, alone or in combination with doxycycline, in an in vitro pharmacodynamic infection model with simulated endocardial vegetations; Aeschlimann JR et al.; Quinupristin-dalfopristin is a streptogramin antibiotic combination with activity against vancomycin-resistant Enterococcus faecium (VREF), but emergence of resistance has been recently reported . We studied the activity of quinupristin-dalfopristin against two clinical strains of VREF (12311 and 12366) in an in vitro pharmacodynamic model with simulated endocardial vegetations (SEVs) to determine the potential for resistance selection and possible strategies for prevention . Baseline MICs/minimal bactericidal concentrations (microg/ml) for quinupristin-dalfopristin, quinupristin, dalfopristin, and doxycycline were 0.25/2, 64/>512, 4/512, and 0.125/8 for VREF 12311 and 0.25/32, 128/>512, 2/128, and 0.25/16 for VREF 12366, respectively . Quinupristin-dalfopristin regimens had significantly less activity against VREF 12366 than VREF 12311 . An 8-microg/ml simulated continuous infusion was the only bactericidal regimen with time to 99.9% killing = 90 hours . The combination of quinupristin-dalfopristin every 8 h with doxycycline resulted in more killing compared to either drug alone . Quinupristin-dalfopristin-resistant mutants (MICs, 4 microg/ml; resistance proportion, approximately 4 x 10(-4)) emerged during the quinupristin-dalfopristin monotherapies for both VREF strains . Resistance was unstable in VREF 12311 and stable in VREF 12366 . The 8-microg/ml continuous infusion or addition of doxycycline to quinupristin-dalfopristin prevented the emergence of resistance for both strains over the 96-h test period . These findings replicated the development of resistance reported in humans and emphasized bacterial factors (drug susceptibility, high inoculum, organism growth phase) and infectious conditions (penetration barriers) which could increase chances for clinical resistance . The combination of quinupristin-dalfopristin with doxycycline and the administration of quinupristin-dalfopristin as a high-dose continuous infusion warrant further study to determine their potential clinical utility. Antimicrob Agents Chemother, 1998 Oct, 42(10), 2564 - 8 Comparison of inhibitory and bactericidal activities and postantibiotic effects of LY333328 and ampicillin used singly and in combination against vancomycin-resistant Enterococcus faecium; Baltch AL et al.; One hundred ninety-five individual vancomycin-resistant Enterococcus faecium (VRE) isolates from five upstate New York hospitals were studied for antimicrobial susceptibilities to LY333328, quinupristin-dalfopristin, teicoplanin, ampicillin, and gentamicin . LY333328 was the most active antibiotic against VRE . The effect of media and methods on the antibacterial activity of LY333328, its synergy with ampicillin, and the postantibiotic effects (PAE) of LY333328 and ampicillin were evaluated . In microdilution tests, the MIC of LY333328 at which 90% of the isolates were inhibited (MIC90) was 2 microg/ml in Mueller-Hinton II (MH II) broth and 1 microg/ml in brain heart infusion (BHI) broth . In contrast, on MH II agar the MIC90 was 4 microg/ml and on BHI agar it was >16 microg/ml . Bactericidal activity was observed for most strains at concentrations from 8 to >/=133 times the MIC of the tube macrodilution in MH II broth . A bactericidal effect of LY333328 plus ampicillin was demonstrated in time-kill studies, but there was great strain-to-strain variability . By the MH II agar dilution method, bacteristatic synergy (defined as a fractional inhibitory concentration of <0.5) with LY333328 and ampicillin was demonstrated for 61% of the strains tested . Under similar conditions, there was synergy with LY333328 and quinupristin-dalfopristin or gentamicin for 27 and 15% of the strains tested, respectively . The PAE of LY333328 was prolonged (23.0 h at 10 times the MIC) . However, 50% normal pooled human serum decreased the PAE to 12.2 h at 10 times the MIC . Test conditions and media had a considerable effect on VRE susceptibilities to LY333328 . The prolonged PAE of LY333328, a potent new bactericidal glycopeptide, and its synergy with ampicillin in a large proportion of strains suggest that further evaluation of this drug in pharmacokinetic studies and experimental infections, including those with VRE, is warranted. Chem Biol, 1998 Sep, 5(9), 489 - 504 Homologs of the vancomycin resistance D-Ala-D-Ala dipeptidase VanX in Streptomyces toyocaensis, Escherichia coli and Synechocystis: attributes of catalytic efficiency, stereoselectivity and regulation with implications for function; Lessard IA et al.; BACKGROUND: Vancomycin-resistant enterococci are pathogenic bacteria that have altered cell-wall peptidoglycan termini (D-alanyl-D-lactate {D-Ala-D-lactate} instead of D-alanyl-D-alanine {D-Ala-D-Ala}), which results in a 1000-fold decreased affinity for binding vancomycin . The metallodipeptidase VanX (EntVanX) is key enzyme in antibiotic resistance as it reduces the cellular pool of the D-Ala-D-Ala dipeptide . RESULTS: A bacterial genome search revealed vanX homologs in Streptomyces toyocaensis (StoVanX), Escherichia coli (EcoVanX), and Synechocystis sp . strain PCC6803 (SynVanX) . Here, the D,D-dipeptidase catalytic activity of all three VanX homologs is validated, and the catalytic efficiencies and diastereoselectivity ratios for dipeptide cleavage are reported . The ecovanX gene is shown to have an RpoS (sigma(s))-dependent promoter typical of genes turned on in stationary phase . Expression of ecovanX and an associated cluster of dipeptide permease genes permitted growth of E . coli using D-Ala-D-Ala as the sole carbon source . CONCLUSIONS: The key residues of the EntVanX active site are strongly conserved in the VanX homologs, suggesting their active-site topologies are similar . StoVanX is a highly efficient D-Ala-D-Ala dipeptidase; its gene is located in a vanHAX operon, consistent with a vancomycin-immunity function . StoVanX is a potential source for the VanX found in gram-positive enterococci . The catalytic efficiencies of D-Ala-D-Ala hydrolysis for EcoVanX and SynVanX are 25-fold lower than for EntVanX, suggesting they have a role in cell-wall turnover . Clustered with the ecovanX gene is a putative dipeptide permease system that imports D-Ala-D-Ala into the cell . The combined action of EcoVanX and the permease could permit the use of D-Ala-D-Ala as a bacterial energy source under starvation conditions. Klin Padiatr, 1998 Jul-Aug, 210(4), 261 - 3 Vancomycin-resistant-enterococci--colonization of 24 patients on a pediatric oncology unit; Schuster F et al.; BACKGROUND: Colonization with multidrug-resistant vancomycin-resistant-enterococci (VRE) could become a serious problem, since there is no proven therapy in case of an infection or in case of transfer of glycopeptid-resistance to other organisms . PATIENTS: Description of 24 from 48 pediatric oncology patients with VRE-colonization . METHODS: Stool samples were taken from all patients of our pediatric oncology unit from March 1996 until June 1997 . Barrier isolation was introduced in May 1996, a prudent use of glycopeptid antibiotica in July 1996 . RESULTS: 193 stool sample examinations demonstrated that 24 (50%) of the 48 patients were colonized with VRE . 11 (46%) of these 24 patients were VRE-carriers at the time of their first examination; 9 (37%) patients acquired VRE during their therapy and 4 (17%) patients had come from other hospitals and already were VRE-positive when they entered our unit . In March 1997, one year after the outbreak only four patients still were VRE-positive, in June 1997 all of them were VRE-negative . The average time of colonization was 12.5 weeks . 17 (70%) of the 24 colonized patients had received glycopeptide antibiotics, 16 of them within two months before the appearance of VRE in their stool . Five colonized patients died, four of them because of their oncological illness, one because of a sepsis without proof of VRE in his blood . In the end none of our patients suffered from a VRE-infection, and besides that, the transfer of glycopeptid-resistance to other organisms was not observed . CONCLUSION: With barrier isolation and a very restrictive use of glycopeptid-antibiotica, colonization can be decreased and even stopped . Inspite of the high number of colonized patients no VRE-infectious disease occurred. Am J Kidney Dis, 1998 Sep, 32(3), 415 - 8 Vancomycin-resistant enterococcus in end-stage renal disease; Brady JP et al.; The percentage of nosocomial vancomycin-resistant enterococci (VRE) has been increasing rapidly in the United States . This has recently resulted in recommendations to reserve vancomycin use for cases with proven resistance to other antimicrobials . We prospectively investigated the incidence of VRE in our dialysis population and compared it with a control group of 40 clinic patients with chronic renal insufficiency (CRI) who had a serum creatinine level greater than 1.5 mg/dL, but were not undergoing dialysis . The incidence of VRE on our campus is almost 10%, which is similar to US data . We studied 50 chronic hemodialysis (HD) patients and 50 peritoneal dialysis (PD) patients . Each patient had a rectal swab test performed and cultured for the presence of enterococci . Antimicrobial exposures over the 6 months before the initial swab test were reviewed in each patient . At least one repeated swab test was performed in 30 CRI, 45 HD, and 37 PD patients . From the initial swab culture, vancomycin-sensitive enterococci (VSE) were isolated in 65% of CRI, 54% of HD, and 70% of PD patients . No CRI or HD patients had VRE isolated and 2% (1 of 50) of PD patients had VRE isolated . The remaining patients had no enterococci isolated . Review of antimicrobial exposures in the 6 months before the initial swab test showed 0% of CRI, 32% of HD, and 36% of PD patients received vancomycin . Other antimicrobials were administered to 40% of CRI, 46% of HD, and 78% of PD patients in the same time period . In the month immediately preceding the initial swab test, 0% of CRI, 12% of HD, and 22% of PD patients received vancomycin and 18% of CRI, 20% of HD, and 36% of PD patients received other antimicrobials . Results from repeated cultures showed that 57% of CRI, 40% of HD, and 38% of PD patients changed their culture status related to VSE, VRE, or no enterococci present . Cultures of 342 swabs from 140 patients yielded three VRE isolates in two patients . We conclude that despite the frequent use of vancomycin and other antimicrobials, the incidence of VRE in our renal population is less than the reported incidence . Given this lack of VRE isolates, we recommend the continued judicious use of vancomycin in treating renal patients and continued enterococcal sensitivity surveillance. J Clin Microbiol, 1998 Oct, 36(10), 2996 - 3001 Use of molecular and reference susceptibility testing methods in a multicenter evaluation of MicroScan dried overnight gram-positive MIC panels for detection of vancomycin and high-level aminoglycoside resistances in enterococci; Chen YS et al.; Modified MicroScan gram-positive MIC no . 8 panels (PM-8) were analyzed for their improved ability to detect vancomycin resistance (VR) and high-level aminoglycoside resistance (HLAR) in enterococci . A validation study design that utilized selected challenge strains, recent clinical isolates, and reproducibility experiments in a multicenter format was selected . Three independent medical centers compared the commercial panels to reference broth microdilution panels (RBM) and Synergy Quad Agar (QA) . Resistance was verified by demonstration of VR and HLAR genes by PCR tests . The study was conducted in three phases . (i) In the challenge phase (CP), two well-characterized sets of enterococci were obtained from the Centers for Disease Control and Prevention; one set contained 50 isolates for VR testing and one contained 48 isolates for HLAR testing . In addition, a set of 47 well-characterized isolates representing diverse geographic areas, obtained from earlier national surveillance studies, was tested at the University of Iowa College of Medicine (UICM) . (ii) In the efficacy phase (EP), each laboratory tested 50 recent, unique clinical isolates by all methods . (iii) In the reproducibility Phase (RP), each laboratory tested the same 10 strains by all methods in triplicate on three separate days . All isolates from the EP were sent to the UICM for molecular characterization of vanA, -B, -C1, -C2-3, and HLAR genes . In the CP, the ranking of test methods by error rates (in parentheses; very major and major errors combined, versus PCR results) were as follows: for high-level streptomycin resistance (HLSR), QA (12.0%) > PM-8 (5.2%) > RBM (1.6%); for high-level gentamicin resistance (HLGR), RBM (3.7%) > PM-8 (3.1%) > QA (2.6%); and for VR, RBM = QA (3.0%) > PM-8 (1.2%) . In the EP, agreement between all methods and the reference PCR result was 98.0% for HLSR, 99.3% for HLGR, and 98 . 6% for VR . In the RP, the percentages of results +/- 1 log2 dilution of the all-participant mode were as follows: for VR, 100% (PM-8), 98.9% (QA), and 90.0% (RBM); for HLSR, 99.6% (RBM), 98.5% (PM-8), and 82.2% (QA); and for HLGR, 99.6% (RBM), 99.3% (PM-8), and 98.1% (QA) . The ability of the PM-8 to detect VR and HLAR in enterococci was comparable to those for reference susceptibility and molecular PCR methods and was considered acceptable for routine clinical laboratory use. Antimicrob Agents Chemother, 1998 Sep, 42(9), 2215 - 20 Glycopeptide antibiotic resistance genes in glycopeptide-producing organisms; Marshall CG et al.; The mechanism of high-level resistance to vancomycin in enterococci consists of the synthesis of peptidoglycan terminating in D-alanyl-D-lactate instead of the usual D-alanyl-D-alanine . This alternate cell wall biosynthesis pathway is ensured by the collective actions of three enzymes: VanH, VanA, and VanX . The origin of this resistance mechanism is unknown . We have cloned three genes encoding homologs of VanH, VanA, and VanX from two organisms which produce glycopeptide antibiotics: the A47934 producer Streptomyces toyocaensis NRRL 15009 and the vanc