Cefoxitin disk diffusion screen for confirmation of oxacillin-resistant Staphylococcus aureus isolates and utility in the clinical laboratory.
One hundred Vitek-2 identified oxacillin resistant S. aureus (ORSA) isolates were tested by oxacillin screen-plate (OXA-plate) and cefoxitin disk (FOX-disk) for confirmation of oxacillin resistance. Ninety-five of 100 confirmed oxacillin resistant by both, 3 of 5 were oxacillin susceptible by both and mecA negative, and 2 of 5 were oxacillin susceptible by OXA-plate, resistant by FOX-disk and mecA positive. The FOX-disk out-performed the OXA-plate for ORSA confirmation and can be performed using standard laboratory techniques.
Sharp
Susan E
SE
Kaiser Permenente, Department of Pathology, Regional Laboratory, Portland, OR, USA. susan.e.sharp@kp.org
Warren
Julie A
JA
Thomson
Richard B
RB
D002440:Cefoxitin / Q000494:pharmacology*; D004058:Diffusion; D024881:Drug Resistance, Bacterial; D006801:Humans; D008826:Microbial Sensitivity Tests; D010068:Oxacillin / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects*
D002440:Cefoxitin; D010068:Oxacillin