Emergence of the vanA genotype among Enterococcus gallinarum isolates colonising the intestinal tract of patients in a university hospital in Rio de Janeiro, Brazil.

We describe the characteristics of seven unusual isolates of vancomycin-resistant enterococci (VRE) carrying both the vanC1 and vanA genes that were detected during a 3-month survey carried out to investigate the occurrence of faecal carriage of VRE. The isolates were identified as Enterococcus gallinarum and showed high-level resistance to both vancomycin and teicoplanin (minimum inhibitory concentrations >256 microg/mL and 64-96 microg/mL, respectively). All seven isolates were also resistant to chloramphenicol, erythromycin and high levels of gentamicin, and showed intermediate susceptibility to both quinolones tested (ciprofloxacin and norfloxacin). Susceptibility to fosfomycin, rifampicin and tetracycline varied among isolates. High-level resistance to gentamicin was associated with the aac(6')-aph(2'') gene, and resistance to erythromycin was associated with the erm(B) gene. The seven vanA-carrying E. gallinarum isolates had similar pulsed-field gel electrophoresis (PFGE) profiles. The emergence of multiple antimicrobial resistance, including high-level resistance to glycopeptides, among E. gallinarum points out the need to increase awareness for detection and proper characterisation of these microorganisms, as they may represent potential reservoirs of transmissible, clinically significant resistance genes in nosocomial settings.