Susceptibility of Gram-positive bacteria from ICU patients in UK hospitals to antimicrobial agents.
Microbiologists in 25 sentinel laboratories were each asked to refer up to 100 clinically-significant Gram-positive bacteria isolated from consecutive intensive care unit (ICU) patients. A total of 1595 isolates were collected from patients in 23 hospitals; these included Staphylococcus aureus (47.6%), coagulase-negative staphylococci (CNS) (30.6%), enterococci (14.3%), pneumococci (2.8%) and other streptococci (3.5%). A few coryneforms, other bacilli and a Nocardia sp. were also collected. Rates of oxacillin resistance among S. aureus and CNS isolates were 59.3 and 78.5%, respectively. Vancomycin-resistant S. aureus were not detected, although two isolates (0.3%) were resistant to teicoplanin [minimum inhibitory concentrations (MICs) 8 mg/L]. In contrast, 13.7% of CNS were teicoplanin resistant (MICs 8-32 mg/L) and 1.2% were resistant to vancomycin. Among the enterococci, 72.5% were Enterococcus faecalis and 24.5% were Enterococcus faecium, the remainder including isolates of Enterococcus casseliflavus or Enterococcus gallinarum. Eighteen percent of E. faecium isolates were vancomycin-resistant, compared with only 3% of E. faecalis isolates. Rates of high-level gentamicin resistance in E. faecalis and E. faecium were 40 and 25%, respectively. Nine percent of pneumococci and streptococci were resistant to penicillin, with 7 and 11%, respectively, resistant to erythromycin. None of the isolates showed resistance to linezolid, with the MICs for the entire study population falling in the range of 0.5-4 mg/L.
Johnson
A P
AP
Antibiotic Resistance Monitoring and Reference Laboratory, Central Public Health Laboratory, Colindale, London, UK. ajohnson@phls.org.uk
Henwood
C
C
Mushtaq
S
S
James
D
D
Warner
M
M
Livermore
D M
DM
D003030:Coagulase / Q000502:physiology; D024881:Drug Resistance, Bacterial / Q000502:physiology; D016983:Enterococcus / Q000302:isolation & purification / Q000502:physiology; D006094:Gram-Positive Bacteria / Q000302:isolation & purification* / Q000502:physiology*; D006801:Humans; D007362:Intensive Care Units; D008826:Microbial Sensitivity Tests / Q000379:methods*; D013210:Staphylococcus / Q000302:isolation & purification / Q000502:physiology; D006113:United Kingdom
D003030:Coagulase