Isolation and characterization of glycopeptide-resistant enterococci from hospitalized patients over a 30-month period.
In February 1996, a Hospital Infection Control Practices Advisory Committee-style screening program was commenced to isolate and subsequently characterize glycopeptide-resistant enterococci (GRE) from patients at a hospital trust in Glasgow, Scotland. Over the next 30 months, GRE were isolated from 154 patients. GRE were isolated from patients in traditionally high-risk areas such as the renal unit and intensive care unit and also in areas considered to be lower risk, including medical wards and associated long-stay geriatric hospitals. The majority (90%) of isolates were Enterococcus faecium vanB. The remaining isolates consisted of seven E. faecalis (vanA), three E. gallinarum (vanC), and a further six E. faecium (five vanA, one both vanA and vanB) isolates. Analysis of SmaI-digested DNA by pulsed-field gel electrophoresis revealed that 34 of 40 (85%) VanB E. faecium isolates were identical or closely related, while 11 of 13 (85%) VanA GRE were distinct. High-level aminoglycoside resistance was seen in less than 8% of isolates. VanB E. faecium isolates were almost uniformly resistant to ampicillin and tetracycline. In this study, GRE have been isolated over a prolonged period from a broad range of patients. Glycopeptide resistance within the study hospital trust appeared to be mainly due to the clonal dissemination of a single strain of E. faecium VanB.
Nelson
R R
RR
Department of Clinical Microbiology, Western Infirmary, Glasgow, United Kingdom.
McGregor
K F
KF
Brown
A R
AR
Amyes
S G
SG
Young
H
H
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics; D015373:Bacterial Typing Techniques; D003428:Cross Infection / Q000453:epidemiology*; D016521:Electrophoresis, Gel, Pulsed-Field; D016983:Enterococcus / Q000145:classification / Q000187:drug effects* / Q000235:genetics; D006020:Glycopeptides; D016908:Gram-Positive Bacterial Infections / Q000453:epidemiology*; D006801:Humans; D017720:Molecular Epidemiology; D012606:Scotland; D020713:Vancomycin Resistance
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D006020:Glycopeptides; C079913:VanB protein, Enterococcus