title: Vancomycin-resistant enterococci (VRE) colonization of high-risk patients in tertiary care Canadian hospitals. Canadian VRE Surveillance Group.
abstract: We isolated 1487 Enterococcus species from 1200 stool specimens collected from high-risk patients in 12 Canadian tertiary care hospitals between October 1995 and November 1996. The composition of the 1487 isolates was 601 vancomycin-sensitive Enterococcus faecalis (40.4%), 667 vancomycin-sensitive Enterococcus faecium (44.9%), 18 vancomycin-resistant (nine isolates MIC 8-16 micrograms/mL; nine isolates MIC > or = 32 micrograms/mL) E. faecium (VREF) (1.2%), 95 vancomycin-sensitive Enterococcus gallinarum (6.4%), 29 vancomycin-resistant (all MICs 8-16 micrograms/mL) E. gallinarum (2.0%), and 77 vancomycin-sensitive Enterococcus casseliflavus (5.2%). Nine of the 18 VREF isolates collected possessed the vanA genotype and were from three patients at one hospital. Two other VREF isolates, of the vanB genotype, were from a single patient at a second hospital, and the remaining seven isolates, also all of the vanB genotype, were from five patients at a third hospital. All VREF were ampicillin resistant (MIC > or = 16 micrograms/mL), streptomycin resistant (MIC > 1000 micrograms/mL), and ciprofloxacin resistant (MIC > or = 4 micrograms/mL). Ten of the 18 VREF were also resistant to gentamicin (MIC > 500 micrograms/mL), while all 18 isolates had quinupristin/dalfopristin MICs < or = 0.5 microgram/mL. In conclusion, high-risk patients in tertiary care Canadian hospitals are rarely colonized (9/1200 patients, 0.75%) with VREF in their lower gastrointestinal tract. These findings correlate well with the lack of reported VREF infection in high-risk patients in Canadian hospitals. Quinupristin/dalfopristin demonstrated excellent in vitro activity against VREF and other non-faecalis species of Enterococcus, many of which also possessed high-level ampicillin, and/or high-level aminoglycoside, and/or ciprofloxacin resistance.
authors.affiliation: Department of Medical Microbiology, Faculty of Medicine, University of Manitoba, Winnipeg, Canada.
authors.forename: J A
authors.initials: JA
authors.lastname: Karlowsky
authors.forename: G G
authors.initials: GG
authors.lastname: Zhanel
authors.forename: D J
authors.initials: DJ
authors.lastname: Hoban
mesh_terms: D002170:Canada; D003428:Cross Infection / Q000382:microbiology*; D016983:Enterococcus / Q000187:drug effects* / Q000235:genetics / Q000254:growth & development; D016908:Gram-Positive Bacterial Infections / Q000382:microbiology*; D006761:Hospitals; D006801:Humans; D008826:Microbial Sensitivity Tests; D012307:Risk Factors; D020713:Vancomycin Resistance