Phenotypic characterization of extended-spectrum-beta‑lactamase producing E. coli from healthy individuals, patients, sewage sludge, cattle, chickens and raw meat

Objective: The present study aimed to determine the frequency and antimicrobial profile of ESBL-producing isolates of E. coli in different environments.

Methods: This cross-sectional study was conducted at The Children’s Hospital and The Institute of Child Health, Lahore from July to December 2015. The faecal specimens from healthy individuals, patients, sewage sludge, cattle, chickens and raw meat (n = 122) were processed for microbiological analysis using MacConkey agar supplemented with cefotaxime. The identification of organisms was confirmed by API 10S and antimicrobial resistance profile was recorded by Kirby-Bauer disc diffusion method.

Results: On the basis of screening, 77 (63.0%) specimens were found to be positive for ESBL production. The confirmation of 74 (60.0%) ESBL producing E. coli was done using double disc synergy test (DDST). The frequency of ESBL producing E. coli was found to be 17 (57.0%) in healthy individuals, 15 (53.0%) in patients, 10 (66.0%) in cattle faeces, 5 (71.0%) in sewage sludge, 14 (70.0%) in raw meat and 13 (59.0%) in chicken faeces. All of these isolates were resistant to cephalosporins and some of these were resistant to fluoroquinolones and meropenem. None of the isolates showed resistance to cefoperazone-sulbactam, imipenem, piperacillin-tazobactam and amikacin.

Conclusion: The prevalence of ESBL-producing E. coli was recorded in all the environments, suggesting a global expansion of these enzymes.