Nosocomial infections due to Methicillin Resistant Staphylococcus aureus (MRSA) has been an element of concern to the medical personnel for the past four decades. Community associated MRSA (CA-MRSA) which was initially considered as more sensitive than hospital acquired MRSA (HA-MRSA) is now presenting with increasing levels of drug resistance. Along with the mecA gene, pvl gene is characteristically present in most isolates of CA-MRSA. To study the varying drug resistant patterns of MRSA isolates with pvl gene. A total of 150 clinical isolates of MRSA analysed in the study were subjected to susceptibility testing to cefoxitin (30 µg) and growth on oxacillin screen agar containing 6 µg/mL of oxacillin for the detection of methicillin resistance. All the isolates which were included in the study, were checked by PCR for the presence of mecA gene, which codes for methicillin resistance and for pvl gene. Amplification of 540bp and 625bp gene fragments in the PCR reaction indicates the presence of mecA and pvl genes respectively. mecA gene was present in all the 150 isolates of MRSA and pvl gene was present only in 26 isolates. Of these 26 isolates that had pvl gene, 14 were in MRSA isolated from outpatient samples and were sensitive to most of the non- beta lactam antibiotics. Among the other 12 inpatient MRSA isolates which had the pvl gene, nine were sensitive to most of the non- beta lactam antibiotics, whereas remaining three were resistant to most of the antibiotics except vancomycin and linezolid. The presence of pvl gene can no longer be used to discriminate between CA-MRSA and HA-MRSA. Indiscriminate empirical treatment of MRSA infections with high end antibiotics like glycopeptides needs to avoided and therapy with non beta lactam antibiotics like lincosamides which have better soft tissue penetration should be used as very few new antimicrobial agents are in the pipeline.

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