Phenotypic and molecular characterization of extended spectrum and#946; lactamase producing Escherichia coli and Klebsiella pneumonia isolates from animal sources

Abstract

Extended-spectrum beta-lactamase producing Enterobacteriaceae has become a newlinemajor threat to both animals and human health globally. The present study was newlineundertaken to isolate and identify ESBL producing Escherichia coli and Klebsiella newlinepneumoniae from various sources, to study their resistant gene profile, to detect insertion newlinesequences, to genogroup the isolates and to compare the efficacy of REP-PCR and PFGE newlineto discriminate ESBL producing E. coli and K. pneumoniae isolates. newlineOut of 385 samples from various sources, 31 (8.05%) were positive for ESBL newlineproducing E. coli. Such isolates could be isolated from 10.05, 8.33, 15.63, 6.67 and 4.35 newlineper cent of cattle milk, curd, chicken, pork and cattle faeces samples, respectively. newlineHowever, no ESBL producing E. coli could be isolated from goat milk, goat faeces and newlinebeef samples. A total of 59 (15.32%) samples were positive for ESBL producing K. newlinepneumoniae, which could be isolated from 14.35, 6.25, 21.43 and 34.78 per cent samples newlineof cattle milk, chicken, beef and cattle faeces, respectively. No ESBL producing K. newlinepneumoniae isolates could, however, be isolated from goat milk and faeces, curd and newlinepork. newlineIn-vitro drug susceptibility assay against 3rd and 4th generation cephalosporins newlineshowed resistance of all the 90 ESBL isolates to at least one antibiotic. In CDT, 93.55% newlineof E. coli and 88.14% K. pneumoniae and in ESBL E test, 96.77% E. coli and 88.14% newlineK. pneumoniae showed positive results. newlineAntibiogram of the ESBL producing E. coli and K. pneumoniae showed newlineresistance of 74.19% and 69.49%, respectively to ceftizoxime, 25.81% and 23.73% to newlineboth co-trimoxazole and tetracycline, 19.35% and 25.42% to ciprofloxacin, 9.68% and newline16.95% to chloramphenicol, 3.23% and 5.08% to pipercillin-tazobactam, and 3.23% and newline3.39% to gentamicin. newlineResistance gene profiling showed blaCTX-M gene to be present in all the 90 newline(100%) ESBL isolates. The blaTEM gene was found in 54.84% and 55.93%, blaSHV newlinegene in 90.32% and 77.97%, Sul 1 gene in 90.32% and 86.44% isolates. The Int1 gene newlinewas detected in 70.97% an