Broth Microdilution Method for Determining Resistance pattern of clinically isolated common pathogenic Microorganisms against conventional antibiotics

Abstract

Antibiotic resistance is a common phenomenon over the years in the world. Gradually more MIC of Fluoroquinolones, Macrolides, Cephalosporins and Vancomycin against 7 isolates of E.coli and Klebsiella, 2 isolates of Salmonella typhi, 1 isolates of Staphylococcus aureus, Pseudomonas and Acinetobacter. At different concentration of drug, organisms were added to 96 well containing microtiter plate. After incubation,optical densities were determined by microtiter plate reader and Minnimum Inhibitory Concentration end point was determined. Fluoroquinolones were sensitive against most isolates of organisms and they showed resistance against gram positive bacteria (Staphylococcus aureus) as Levofloxacin is considered to be active against gram positive bacteria so further study should be carried out. In case of, MIC of Azithromycin against most isolates of gram negative bacteria were sensitive however, Azithromycin showed resistance against some isolates of E.coli so further study should be carried out.