Enterococcal bacteremia in a tertiary care centre in Winnipeg

To review experience with enterococcal bacteremia before the emergence of vancomycin-resistant enterococcus at a tertiary care teaching hospital.

Retrospective chart review of episodes of enterococcal bacteremia identified through the clinical microbiology laboratory from January 1990 to December 1994. Antimicrobial susceptibilities were performed for all isolates and pulsed-field gel electrophoresis for genetic typing of selected strains.

One hundred and twenty-six episodes of bacteremia were identified in 109 patients: 108 Enterococcus faecalis, 13 Enterococcus faecium, four both E faecalis and E faecium, and one Enterococcus durans. Enterococcal isolates occurred with polymicrobial bacteremia in 62 (49%) episodes. The most common sites of infection were central venous catheters (45%) and the urinary tract (21%). Enterococcal bacteremia was usually nosocomially acquired (88%), and associated with older age, instrumentation, and prior or current antimicrobial therapy. Overall mortality was 22%, and 7.2% was partially or fully attributable to enterococcal bacteremia. Resistance to ampicillin, high level gentamicin and high level streptomycin were 0%, 32% and 31% for E faecalis, respectively, and 44%, 0% and 47% for E faecium, respectively.

During this review, the frequency and impact of enterococcal bacteremia at this institution was relatively limited. Isolates resistant to ampicillin and aminoglycosides were emerging, but differences in patient outcomes were similar for resistant and susceptible isolates.