Comparison of Oxacillin and Cefoxitin for the Detection of mecA Gene to Determine Methicillin Resistance in Coagulase Negative Staphylococci (CoNs)

作者：Shah Dania Aijaz; Wasim Shehnaz; Abdullah Farhan Essa^*

来源：Journal of the College of Physicians and Surgeons Pakistan, 2017, 27(8): 520-522.

• Cefoxitin
• Methicillin
• Oxacillin
• mecA gene
• Methicillin resistant coagulase-negative staphylococci

The aim of the study was to compare the effectiveness of Cefoxitin with that of Methicillin/Oxacillin in the determination of mecA gene in Methicillin resistant Coagulase-negative staphylococci (CoNS). We assessed 57 CoNS isolates for mecA gene via PCR, which were subsequently subjected to Methicillin/Oxacillin and Cefoxitin disc diffusion test. These methods are simple, inexpensive and easily available compared to PCR despite less specificity. Out of 41 mecA positive species, 33 (80.5%) were resistant to Methicillin/Oxacillin. Cefoxitin-resistance was seen in all 41 (100%) mecA positive samples. Two (12.5%) mecA negative isolates of S. saprophyticus were Methicillin/Oxacillin resistant, but were Cefoxitin sensitive. Four (9.7%) isolates of S. saprophyticus, three (7.3%) of S. epidermidis species, and one (2.4%) S. haemolyticus that were mecA positive were sensitive to Methicillin/Oxacillin but resistant to Cefoxitin. Cefoxitin resistance provides a more accurate picture of mecA gene positivity as compared to Methicillin and Oxacillin.

• 出版日期2017-8