Evaluation of cefoxitin disk diffusion test for the detection of methicillin resistant Staphylococcus aureus / 临床检验杂志

ABSTRACT

Objective To establish and evaluate the method for detection of methicillin-resistant Staphylococcus aureus (MRSA) by the cefoxitin disk diffusion test.Methods The disks with 30 microgramme of cefoxitin and oxacillin recommended by NCCLS were used for the detection of MRSA with PCR by using mecA as the reference.The MIC of cefoxitin to Staphylococcus aureus was also determined.Results Of the 145 test isolates of Staphylococcus aureus,83 isolates showed the mecA-positive by PCR,62 isolates were negative.In cefoxitin disk diffusion tests,82 isolates showed MRSA-positive and 63 isolates were negative.The sensitivity was 98.8% and the specificity was 100%.In oxacillin diffusion tests,the sensitivity was 95.2% and the specificity was 96.8%.Conclusions For the detection of MRSA,the cefoxitin disk diffusion test was consistent with the results by PCR for mecA.The cefoxitin disk diffusion test is easy to be performed and can be used in routine diagnostic works.