Mupirocin resistance among consecutive isolates of oxacillin-resistant and borderline oxacillin-resistant Staphylococcus aureus at a university hospital.
Mupirocin resistance was determined in consecutive oxacillin-resistant and borderline oxacillin-resistant Staphylococcus aureus clinical isolates collected over 14 months at a university hospital during 1991 and 1992. Twenty of 86 (23%) oxacillin-resistant and borderline oxacillin-resistant S. aureus isolates were mupirocin resistant; 80% were high-level resistant. Prior mupirocin use was a significant risk factor (relative risk, 6.08; 95% confidence interval, 3.7 to 9.99). Seven of 20 resistant isolates were distinct strains, as determined by pulsed-field gel electrophoresis typing. Two instances of clonal dissemination of a single strain occurred, but several other distinct mupirocin-resistant strains were documented. Mupirocin resistance was unexpectedly common among these isolates.
Layton
M C
MC
Department of Medicine, Yale University School of Medicine, New Haven, Connecticut 06520.
Patterson
J E
JE
D004269:DNA, Bacterial / Q000032:analysis; D004352:Drug Resistance, Microbial; D006785:Hospitals, University; D006801:Humans; D016712:Mupirocin / Q000494:pharmacology*; D010068:Oxacillin / Q000494:pharmacology*; D010403:Penicillin Resistance; D013203:Staphylococcal Infections / Q000382:microbiology; D013211:Staphylococcus aureus / Q000187:drug effects*; D014481:United States
D004269:DNA, Bacterial; D016712:Mupirocin; D010068:Oxacillin