StaphylococcalCassette Chromosome mec (SCCmec) Typing of Clinical Isolates of staphylococcus aureus by Multiplex PCR

The widespread use of various antibiotics has been responsible for the resistance of Staphylococcus aureusto the antibiotics. Methicillin resistance has become especially important because of limiting therapeutic options. Therefore, in this study we evaluated drug resistance and genotyping of staphylococcal cassette chromosome mec(SCCmec) in S.aureusstrains isolated from patients admitted in Tehran hospitals.

The 215 clinical isolates of S. aureuswas collected from clinical specimens. Antibiotic susceptibility was determined by disk diffusion. PCR was performed to identify the mecA gene. Different types of SCC mecwere identified using the Multiplex PCR method.

The highest resistance was observed for tetracyclin (49.3%), oxacilin (46.04%) and erythromcin (36.5%), followed by ciprofloxacin (29.7%), gentamycin (28.3%), clindamycin (27.4%), co-trimoxazole (23.3%) and vancomycin (0). The frequency of mecA gene was 46.44%. Multiplex PCR analysis showed that the distribution of different types of SCCmecin this study was the SCCmecIII (88.9%), SCCmecII (03.03%), SCCmecI (02.2%), and none typable (6.5%).

It seems that there is a genetic diversity among MRSA circulating in studied hospitals that highlights the need to implement appropriate infection control policies in order to decrease dissemination of multi-drug resistance MRSA types in our hospitals