Study on antibiotic resistance by pathogenic bacteria isolated from clinical specimen

An attempt was made to isolate and study the resistance of bacterial pathogens fromclinical specimens (stool, blood and skin lesion) of hospitalized patients against threeantibiotics viz., erythromycin, tetracycline and penicillin G. Seven different strains ofpathogenic bacteria viz., Salmonella typhi, S. paratyphi, A. shigella dysenteriae, S. sonnei,Staphylococcus aureus, Enterobacter aerogenes and Escherichia coli were isolated. All theisolates were found resistance to penicillin G and tetracycline except S. typhi and S. sonneiwhich were found sensitive to tetracycline. On the other hand, all the isolates were found tobe sensitive against erythromycin tested herein and the highest zone of inhibition (26 mm)was recorded against S. typhi. Subsequent agarose gel electrophoresis showed no plasmid-DNAband in the gel indicating that observed resistance was chromosomal gene-mediated.