Comparative study on detection of MRSA using oxacillin agar screening method, cefoxitin disc diffusion method and mecAgene by PCR among clinical isolates of Staphylococcus aureus.

Abstract

Cefoxitin is a good marker of the mecA regulatory system. It is being recommended for detection of methicillin resistance in Staphylococcus aureus (MRSA) using disk diffusion testing. The aim of our study was to evaluate the efficacy of cefoxitin disc diffusion test to characterize MRSA and compare it with oxacillin agar screening and detection of mecA gene by PCR. We have observed 100% sensitivity and specificity in cefoxitin disc diffusion method over detecting mecA gene by PCR. Results of cefoxitin disc diffusion test is in concordance with the PCR for mecA gene. Thus, the test can be an alternative to PCR for detection of MRSA in resource constraint settings.