Prevalence of ESBLs and MBLs among Escherichia coli and Klebsiella pneumoniae Isolates from a Nigerian Abattoir

Abstract

Background: Food products of animal origin play significant role in the transfer of antibiotic resistance. This work evaluated the antibiotic resistance profile and prevalence of beta-lactamases producing Escherichia coli and Klebsiella pneumoniae isolates in an abattoir in Awka, Nigeria. Methods: One hundred swab samples were aseptically collected from the abattoir between January to April 2016 with sterile swab sticks and cultured in freshly prepared nutrient broth and MacConkey agar plates. E. coli and K. pneumoniae isolates were identified using standard microbiological identification techniques. The isolates were evaluated for antibiotic susceptibility and for the expression of ESBL, MBL and AmpC β-lactamases. Findings: Ninety-four isolates comprising 60 E. coli and 34 K. pneumoniae were bacteriologically obtained from the abattoir samples. Their antibiotic resistances pattern was in the order of: erythromycin>cloxacillin>cefuroxime>augmentin>ceftriaxone>ceftazidime>ofloxacin>gentamicin (E.coli isolates) & erythromycin>cloxacillin>cefuroxime>augmentin>ofloxacin> ceftriaxone>gentamicin>ceftazidime (for K. pneumoniae isolates). Seven (12%) of the E. coli isolates and 15% K. pneumoniae isolates were confirmed phenotypically to be ESBL producers. None of the isolates was AmpC producing but 10% E. coli and 12% isolates of K. pneumoniae were confirmed to be MBL-producers. Abattoir isolates harbor resistance traits for the expression of ESBL and MBL-which are responsible for the MDR nature of Gram-negative bacteria and could serve as route via which these organisms can be transmitted through the food chain.