MOLECULAR CHARACTERISATION OF EXTENDED-SPECTRUM μ-LACTAMASE-PRODUCING ESCHERICHIA COLI AND SALMONELLA ISOLATED FROM POULTRY AND POULTRY PRODUCTS IN EGYPT.

Extended-spectrum β-lactamase (ESBL) producing E. coli and salmonellae have spread rapidly worldwide and pose a serious threat to human and animal health. The present study was conducted to determine the prevalence of ESBL-producing E.coli and salmonellae, to perform molecular characterisation of the ESBL-related bla genes, including blaTEM, blaSHV and blaCTX, and the susceptibilities of these bacteria to various antimicrobial agents. From a total of 300 poultry samples, 25 and 20 samples were recognised as Salmonella and E. coli, respectively by microbiological and molecular methods. All E. coli and Salmonella isolates were positive for an ESBL phenotype. Molecular detection for antibiotic resistance gene revealed blaTEM in all isolates of salmonellae and E. coli (100%), while blaSHV was detected in 5 (20%) and 2 (10%) of salmonellae and E. coli isolates, respectively. None of the isolates contained blaCTX gene. Serotyping of Salmonella spp. in chickens revealed that S. enteritidis was the major isolates followed by S. Infantis (21.4%), S. Kentucky (14.2%) and S. Typhimurium, S. Kapemba, S. Newport, S. Vejle and S. Magherafelt were detected at 7.1% respectively. S. Infantis was the major isolate detected in chicks (60%), while in ducks S. Typhimurium and S. Blegdam were identified. In ducklings, S. Sinchew, S. Infantis and S. Sekondi were equally prevalent. Only S. Newmexico was identified in poultry products. E. coli in chicken were serotyped into O1, O8, O29, O125, O128 and O157. In chicks, O29 and O126 serotypes were detected. In poultry products only O8 was detected. The results indicate that ESBL frequency has reached an alarming level in poultry isolates in Egypt, with TEM enzymes being the predominant β-lactamases detected. [ABSTRACT FROM AUTHOR]