Determination of Resistance pattern of Gram positive(+) and Gram Negative (-) Microorganisms against Antibiotic Standard Powder

Abstract

Antibiotic susceptibility is the susceptibility of bacteria to antibiotics. Antibiotic resistance is the ability of microbes to resist the effects of drugs. The main objective of the study was to determine MIC value of Fluoroquinolones, Cephalosporins, Azithromycin and Vancomycin against 7 isolates of E.coli, 5 isolates of Klebsiella, 2 isolates Salmonella typhi of and 1 isolates of Staphyloococcua aureus and Acinetobacter using broth microdilution. At different concentration of drug organisms were added to 96 well microtiter plate. After incubation optical densities were determined by microtiter plate reader and Minnimum Inhibitory Concentration end point was determined. MIC obtained by this study of fluoroquinolones, Azithromycin and Vancomycin were sensitive for different clinical isolates. But Cephalosporin drugs (cephradine and ceftriaxone) had shown resistance to different isolates of gram positive and gram negative bacteria. Ceftriaxone is a 3rd generation cephalosporin drug which showed resistance to many isolates of different organism. So, further study should be carried out for ceftriaxone using other different methods to determine its susceptibility for different microorganism