Prevalence and antibiotic resistance of extended- spectrum beta-lactamase (ESBL) producing Escherichia coli and Klebsiella species isolated from foods of animal origin in Turkey

The present study includes 50 Klebsiella oxytoca, 45 Escherichia coli and 13 Klebsiella pneumoniae isolated from raw meat (chicken drumsticks and minced meat), raw milk, white cheese and ice cream samples and was undertaken to determine the prevalence of extended-spectrum β-lactamase (ESBL)-producing isolates and antibiotic resistance. The double-disk synergy test was used to determine ESBL production. ESBL production was detected in 20 of 45 E. coli (44.4%), 5 of 13 K. pneumoniae (38.5%) and 13 of 50 K. oxytoca (26%) isolates. Resistance of all isolates to 14 antibiotics was determined by the disk diffusion method. All isolates showed resistance to ampicillin but none exhibited resistance to imipenem, ertapenem, cefepime and piperacillin/tazobactam. E. coli andKlebsiella spp. isolates have also been found resistant to cefotaxime, ceftazidime, ceftriaxone, aztroenam, tetracycline and ciprofloxacin. All isolates were resistant to two or more antimicrobial agents.   Key words: β-Lactamases, antibiotic resistance, Escherichia coli, Klebsiella spp., foods.