Prevalence of Extended Spectrum Β-Lactamase (ESBL) Producing Escherichia coli and Molecular Characterization of ESBL, Carbapenemases, and Blacmy2 Genes in Broilers and Humans at Menoufia Governorate, Egypt

Abstract

Antibiotic resistance is a serious worldwide problem threatening human health and life.Poultry, especially broilers, represent a major source of ESBL-producing E. coli due to theextensive use of antibiotics during their production. This study investigated the prevalenceof ESBL-EC in broilers, the surrounding environment, and humans, as well as theoccurrence of ESBLs, carbapenemases, and blaCMY2 genes. 249 samples were included inthat study: 130 broiler cloacal swabs, 54 environmental samples, and 65 human samples.All samples were grown on Macconkey broth, then cultured on EMB containing cefotaximesodium. Suspected E. coli isolates were identified and confirmed biochemically by IMVICtests. The disc diffusion method was used to determine the antibiotic susceptibility patternof E. coli isolates grown on EMB with cefotaxime. PCR was performed for the amplificationof ESBLs, carbapenemases, and blaCMY2 genes. Our results revealed that ESBL-EC wasisolated from 180 (72.3%) of the 249 collected samples. The prevalence of ESBL-producingE. coli was as follows: 85.4%, 46.3%, and 67.7% in broiler cloacal swabs, environmentalsamples, and human samples, respectively. Among 188 E. coli isolates grown on EMBcontaining cefotaxime, 187 were resistant to CTX, 170 to CAZ, 166 to FEP, and 146 to FOX.PCR amplification showed that the predominant gene was blaTEM, which was detected in98% of the amplified isolates, followed by blaCTX-M (88%). BlaKPC wasn't detected in anyisolates. Many gene combinations were detected, and the most common one was blaTEMwith blaCTX-M, which was detected in 24 (48%) of the 50 isolates.