Comparative analysis of minimum inhibitory concentration of various brands of cephalosporin against clinical isolates of Staphylococcus aureus

Staphylococcus aureus poses a serious global threat due to difficulty in treatment of its multi-drug resistant strains. One hundred and fifty isolates were collected from pathology laboratory of Nashtar Medical Hospital, Multan; out of which, 50% isolates were found resistant to erythromycin, 100% to carbenicillin and 97% to ampicillin. Vancomycin was comparatively most effective as compared to other antibiotics. Regarding the cephalosporin groups, cefotaxime (73%), ceftazidime (81%), ceftriaxone 82%, cefaclor and cefoperazone (90%) and cephradine was 50% effective against these isolates. Bacterial resistance of twenty five isolated and identified strains of S. aureus were tested against local and multinational brands from 1st, 2nd and 3rd generations’ injectables. It was noted that 1st generation brands were more resistant than 2nd and 3rd generation. On the basis of mean value, minimum inhibitory concentration (MIC) of local brands were better than multinational brands but on the basis of statistical analysis by ANOVA, the MIC obtained for local and multinational brands were equally effective against theS. aureus isolates. Key words: Staphylococcus aureus, antibiotics, local and multinational brands, cephalosporins, minimum inhibitory concentration.