Linkage of determinants for streptogramin A, macrolide-lincosamide-streptogramin B, and chloramphenicol resistance on a conjugative plasmid in Enterococcus faecium and dissemination of this cluster among streptogramin-resistant enterococci.

A new streptogramin A resistance gene, satG (= vatE), has been recently identified in Enterococcus faecium UW1965 (Werner and Witte 1999. Antimicrob. Agents Chemother.

In vitro activity of gatifloxacin compared with gemifloxacin, moxifloxacin, trovafloxacin, ciprofloxacin and ofloxacin against uropathogens cultured from patients with complicated urinary tract infections.

Minimum inhibitory concentrations (MICs) of gatifloxacin were compared with those of gemifloxacin, moxifloxacin, trovafloxacin, ciprofloxacin and ofloxacin using an agar dilution method for 400 uropathogens cultured from the urine of urological patients with complicated and/or hospital-acquired urinary tract infections (UTI). The collection of strains was made up of Enterobacteriaceae (34.5%), enterococci (31.

Effect of subinhibitory antibiotic concentrations on polysaccharide intercellular adhesin expression in biofilm-forming Staphylococcus epidermidis.

Biofilm production is an important step in the pathogenesis of Staphylococcus epidermidis polymer-associated infections and depends on the expression of the icaADBC operon leading to the synthesis of a polysaccharide intercellular adhesin. A chromosomally encoded reporter gene fusion between the ica promoter and the beta-galactosidase gene lacZ from Escherichia coli was constructed and used to investigate the influence of both environmental factors and subinhibitory concentrations of different antibiotics on ica expression in S. epidermidis.

Impact of flavophospholipol and vancomycin on conjugational transfer of vancomycin resistance plasmids.

The influence of vancomycin and flavophospholipol (FPL) on the transfer rate of conjugative plasmids harboring the vancomycin resistance operon vanA was determined in several clinical and animal isolates of Enterococcus faecium. FPL significantly inhibited the frequency of transfer of conjugative VanA plasmids up to 70-fold. Vancomycin had no significant effect on the transfer rate of VanA plasmids.

Multicenter evaluation of epidemiological typing of methicillin-resistant Staphylococcus aureus strains by repetitive-element PCR analysis. The European Study Group on Epidemiological Markers of the ESCMID.

Rapid and efficient epidemiologic typing systems would be useful to monitor transmission of methicillin-resistant Staphylococcus aureus (MRSA) at both local and interregional levels. To evaluate the intralaboratory performance and interlaboratory reproducibility of three recently developed repeat-element PCR (rep-PCR) methods for the typing of MRSA, 50 MRSA strains characterized by pulsed-field gel electrophoresis (PFGE) (SmaI) analysis and epidemiological data were blindly typed by inter-IS256, 16S-23S ribosomal DNA (rDNA), and MP3 PCR in 12 laboratories in eight countries using standard reagents and protocols. Performance of typing was defined by reproducibility (R), discriminatory power (D), and agreement with PFGE analysis.

Selective pressure by antibiotics as feed additives.

Antibacterial substances are used in considerable amounts as growth promoters in animal husbandry. There are, however, incalculable risks for human health resulting from the use of particular feed additives. Even 30 years ago the detection of transferable antibiotic resistance in Enterobacteriaceae led to the demand that antibiotics used in human chemotherapy, or for which cross-resistance against human therapeutics has been demonstrated, should be prohibited as growth promoters.

Quinupristin/dalfopristin-resistant enterococci of the satA (vatD) and satG (vatE) genotypes from different ecological origins in Germany.

The semisynthetic streptogramin combination quinupristin/dalfopristin (Synercid) is a promising alternative for treatment of infections due to multiply resistant gram-positive bacteria including vancomycin-resistant Enterococcus faecium. Resistance is mediated by acetyltransferases SatA (VatD) or SatG (VatE). Recent papers have indicated a possible link between the use of the streptogramin virginiamycin S/M as a feed additive in commercial animal husbandry and a selection of quinupristin/dalfopristin-resistant E.

Ecological impact of antibiotic use in animals on different complex microflora: environment.

Different means of interaction between microecological systems in different animal hosts (including humans) and the environment may occur during the transfer of resistant bacteria and their resistance genes. Spread of resistance takes place in different ways with respect to clonal spread of resistance strains by the spread of wide host range plasmids and translocatable elements. Commensals in ecosystems have a special significance and a pronounced capacity for acquisition and transfer of resistance genes as with Enterococcus faecium and Escherichia coli in the gut flora or Pseudomonas spp.

Nosocomial cross transmission as a primary cause of vancomycin-resistant enterococci in Austria.

Stool specimens from 226 patients from intensive care units (N=69), general wards (N=112), and outpatient-clinics (N=45) at the Innsbruck University Hospital and from 433 healthy volunteers were inoculated on to Enterococcosel Agar supplemented with 5 microg/mL vancomycin and 4 microg/mL cefodizime. Faecal specimens from 105 dairy cows, 171 pigs and 47 egg-laying hens were processed the same way. Thirteen of 226 patients (5.

Antibiotic resistance in gram-positive bacteria: epidemiological aspects.

The emergence and spread of antibiotic resistance in gram-positive bacterial pathogens has become an increasing problem. There has been a dramatic increase in the prevalence of methicillin-resistant Staphylococcus aureus (MRSA), coagulase-negative staphylococci and enterococci. This is mainly due to the clonal dissemination of certain epidemic multiply-resistant strains, for example, those of MRSA and S.

Practical approach to the identification of clinically relevant Enterococcus species.

Enterococci have become important nosocomial pathogens, with Enterococcus faecalis and then Enterococcus faecium predominating. Because of the emergence of glycopeptide (vancomycin and teicoplanin) resistance in enterococci, laboratories have been required to screen for resistant strains and to identify them to the species level. This has resulted in the need for accurate identification of species less commonly associated with clinical infections, such as Enterococcus casseliflavus and Enterococcus gallinarum, which are inherently resistant to the glycopeptides.

Phages for methicillin-resistant Staphylococcus aureus: an international trial.

An internationally agreed and validated set of phages is used worldwide for the typing of strains of Staphylococcus aureus of human origin. However, because of the sometimes reduced susceptibility of methicillin-resistant strains (MRSA) to these phages, some of the national typing centres use locally isolated and characterized sets of experimental phages. In this trial, 42 such phages were distributed to 6 centres and tested against 744 isolates of MRSA with the intention of defining a phage set to augment the international set.

Outbreak of methicillin-resistant Staphylococcus aureus in a German tertiary-care hospital.

A biphasic outbreak of methicillin-resistant Staphylococcus aureus in intensive-care units of a German tertiary-care hospital afflicted 89 patients within 4 years. The spread of the outbreak most likely was facilitated by the contamination of mobile radiograph equipment. The outbreak was controlled by measures of hospital hygiene.

Decreased incidence of VanA-type vancomycin-resistant enterococci isolated from poultry meat and from fecal samples of humans in the community after discontinuation of avoparcin usage in animal husbandry.

The use of the glycopeptide antibiotic avoparcin (AVO) as a feed additive in animal husbandry of many European countries led in 1994-1995 to frequent isolation of VanA-type vancomycin-resistant enterococci (VRE) from commercially produced animal foodstuffs as well as from fecal samples of nonhospitalized persons in Germany (Saxony-Anhalt state). However, at the end of 1997, a decreasing number of such VRE was detected in frozen and fresh poultry meat (chickens and turkeys) from German producers. At this point in time, AVO had been discontinued in animal husbandry for more than 2 and one-half years in Denmark/Norway, nearly 2 years in Germany, and about 8-9 months in all countries of the European Community and Switzerland, respectively.

Survey of antibiotic resistance among enterococci in North Rhine-Westphalia, Germany.

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.