Resistance pattern of antibiotics against clinical isolates of Staphylococcus aureus.

The present research was conducted to study the susceptibility and resistance pattern of Staphylococcus aureus isolates against various brands of commonly used antibiotics. A total of 50 bacterial isolates were obtained from various clinical specimens submitted to the clinical laboratory of Pakistan Institute of Medical Sciences Islamabad (PIMS). Out of 50 isolates 30 (60%) were identified as coagulase positive Staphylococcus aureus. These isolates were tested for susceptibility pattern 19 (63%), these isolates were resistant to penicillin, 17 (57%) to ampicillin, 19 (63%) to cloxacillin, 20 (67%) to streptomycin, 11 (37%) to clindamycin, 16 (53%) to lincomycin and 19 (63%) to neomycin. These isolates had MIC range of penicillin and lincomycin ( 512 microg/mL), ampicillin, cloxacillin and clindamycin (0.5 to 256 microg/mL), streptomycin (4 to >512 microg/mL) and neomycin (2 to 256 microg/mL). Clindamycin was found to be the most effective among these antibiotics tested in the study against these clinical isolates.