Stool Carriage, Clinical Isolation, and Mortality During an Outbreak of Vancomycin-Resistant Enterococci in Hospitalized Medical and/or Surgical Patients

Abstract

During a nosocomial outbreak of infection due to vancomycin-resistant enterococci (VRE), rectal swabs that were collected weekly were used to identify and isolate VRE carriers. Over 6 months, 1,458 stool specimens from 724 high-risk patients were cultured, and 187 VRE isolates were recovered from 61 patients; 96% of the isolates were Enterococcus faecium. VRE tended to be isolated from clinical specimens from patients identified as VRE carriers by stool surveillance (P < .01). However, isolation of VRE from surveillance cultures preceded clinical isolation for only approximately 50% of the patients from whom a clinical VRE isolate was recovered. Mortality was greater (P < .05) among patients from whom a clinical VRE isolate was recovered than among patients from whom VRE was isolated only by stool surveillance. The mortality (1[17%] of 6) among patients for whom VRE was isolated from blood was similar to that (10 [27%] of 37) among patients for whom vancomycin-susceptible enterococcus was isolated from blood (P = .97). Despite prompt initiation of contact precautions for VRE carriers, the incidence of fecal carriage of VRE remained approximately 8% among this patient population for the 6-month period of the study.