Prevalence and molecular epidemiology of glycopeptide-resistant enterococci in Belgian renal dialysis units.

The molecular epidemiology of glycopeptide-resistant enterococci (GRE) colonizing the intestinal tracts of Belgian renal dialysis patients was studied among 1318 patients of a population of 1800 dialysis patients from 29 dialysis centers. Of these, 185 patients (14.0%) were colonized with a VANA-positive GRE; GRE harboring the VANB gene were not detected. The majority of the VANA GRE (80.5%) were identified as Enterococcus faecium; 14.8% were identified as E. faecalis; and a limited number were identified as E. avium, E. casseliflavus, E. dispar, E. durans, or E. gallinarum. Genome analysis of 277 VANA-positive GRE by pulsed-field gel electrophoresis revealed a high genetic variability both within the different dialysis centers and within the patients' own GRE flora. No high-level gentamicin-resistant VANA-positive GRE were detected, and most strains remained susceptible to ampicillin. These findings do not support a hospital-driven endemicity of VANA-positive enterococcal isolates in Belgium.