2.2.2. Determination of VRE

After isolation and identification of suspected VRE colonies antibiotic susceptibility was determined for ampicillin (AM), vancomycin (VA), teicoplanin (TEC), linezolid (LZD), tigecycline (TGC) and trimethoprim/sulfamethoxazole (SXT) by disc diffusion test according to the EUCAST guidelines (EUCAST V2.0, 2012). *E. faecalis* DSM20478 was used as reference. The minimal inhibition concentration (MIC) for 22 antibiotics was assigned by VITEK®2 using the AST-P586 card (bioMérieux, Marcy-l'Etoile, France). Resistance to the glycopeptides vancomycin and teicoplanin was confirmed by Etest (bioMérieux, Marcy-l'Etoile, France) according to the manufacturer's instructions. The detection of the vancomycin resistance genes (*vanA/vanB)* was performed by real time PCR applying the Light cycler VRE Detection Kit (Roche, Branchburg, NJ, USA).
