In the treatment of MRSA infection, rapid detection of MRSA is extremely important. The mecA gene codes the new drug resistant polypeptides called PBP2'which mediates the clinically relevant resistance to all beta-lactam antibiotics. The identical mecA gene has been found in coagulase-negative staphylococcus with the methicillin-resistant phenotype. On the other hand, the femA gene was absent from coagulase negative staphylococcus strains with the methicillin resistant phenotype. This study is aimed at early detection and definite diagnosis of MRSA.

A total of 24 MRSA strains were studied. All strains were tested for antimicrobial susceptibility and purified DNA. We amplified both mecA and femA genes by PCR in 24 strains.

In MRSA all the 16 strains (100%) carried femA gene and 11 strains (68.7%) carried mecA gene. In contrast, in methicillin sensitive staphylococcus all the 8 strains (100%) carried femA and only 3 strains (37.5%) were detected mecA.

As results, there are difference in the phenotype and genotype of methicillin resistance by PCR of mecA and femA. Such disparities between methicillin resistance and the presence of mecA gene suggest the presellce of control gene of the meccA.