COMPARISON OF RAPID METHOD OF DNA EXTRACTION USING MICROWAVE IRRADIATION WITH CONVENTIONAL PHENOL CHLOROFORM TECHNIQUE FOR USE IN MULTIPLEX PCR FOR mec A AND fem B GENES TO IDENTIFY GENOTYPES OF MRSA FROM CULTURES.

Methicillin Resistant Staphylococcus aureus (MRSA) infection is a major cause of morbidity and mortality in hospitalised patients and requires vancomycin for effective therapy. Rapid identification of MRSA is vital to control MRSA outbreaks in hospitals. Identification of MRSA is a time consuming process requiring more than 48 hours and is labour intensive involving culture, biochemical tests and antimicrobial susceptibility testing. In this study we have used microwave irradiation of the bacterium obtained from cultures which was then directly subjected to a multiplex PCR technique to accurately and rapidly identify the presence of mec A and fem B genes which characterise MRSA. This has been compared with the standard method of lysing the bacterium and DNA extraction using phenol chloroform method followed by multiplex PCR. The microwave lysis method followed by direct PCR has been found to be less time consuming, 5 hours, as compared to 9 hours by conventional technique. Use of this strategy would enable early identification and early implementation of control measures.