Outcome of a screening program for vancomycin-resistant enterococci in a hospital in Victoria.

Abstract

Objective: To screen for faecal colonisation with vancomycin-resistant enterococci (VRE) among potentially at-risk patients. Design(s): Infection control screening program. Setting(s): Monash Medical Centre (a tertiary care hospital), Melbourne, Victoria, in the seven months from June 1997. Patient(s): Patients in the Renal, Oncology and Intensive Care (ICU) Units. Main Outcome Measure(s): Presence of VRE in a rectal swab or faecal specimen taken at admission and at regular intervals during inpatient stay; presence of vancomycin-resistance genes (vanA, vanB and vanC) assessed by polymerase chain reaction (PCR); genetic clonality of isolates assessed by pulsed-field gel electrophoresis (PFGE). Result(s): 574 patients (356 renal, 134 ICU and 84 oncology) were screened; 12 were colonised with VRE - nine renal inpatients, two having peritoneal dialysis or in-centre haemodialysis, and one ICU patient. Nine isolates were Enterococcus faecalis (seven positive for vanB and two negative for all three resistance genes) and three were Enterococcus faecium (all positive for vanB). Eight were high-level gentamicin resistant. PFGE suggested genetic clonality between the index isolate and five other isolates from renal patients. No specific clinical practice was associated with VRE colonisation. Attempts to clear rectal carriage with oral ampicillin/amoxyciliin or bacitracin were of limited success. Although antibiotic prescribing in the Renal Unit was generally consistent with defined protocols, use of vancomycin and third-generation cephalosporins has been further restricted. Conclusion(s): Renal inpatients in our institution appear most at risk of VRE colonisation (4.6% overall) and thereore of VRE infection. Routine screening, especially of potentially high-risk patients, should be considered in major Australian hospitals.