Distribution of ß-Lactamase Genes Among Multidrug-Resistant and Extended-Spectrum ß-Lactamase-Producing Diarrheagenic Escherichia coli from Under-Five Children in Ethiopia

PURPOSE: Escherichia coli strains that produce extended-spectrum ß-lactamase (ESBL) and carbapenemase are among the major threats to global health. The objective of the present study was to determine the distribution of ß-lactamase genes among multidrug-resistant (MDR) and ESBL-producing Diarrheagenic E. coli (DEC) pathotypes isolated from under-five children in Ethiopia. PATIENTS AND METHODS: A cross-sectional study was conducted in Addis Ababa and Debre Berhan, Ethiopia. It was a health-facility-based study and conducted between December 2020 and August 2021. A total of 476 under-five children participated in the study. DEC pathotypes were detected by conventional Polymerase Chain Reaction (PCR) assay. After evaluating the antimicrobial susceptibility profile of the DEC strains by disk diffusion method, confirmation test was done for ESBL and carbapenemase production. ß-lactamase encoding genes were identified from phenotypically ESBLs and carbapenemase positive DEC strains using PCR assay. RESULTS: In total, 183 DEC pathotypes were isolated from the 476 under-five children. Seventy-nine (43%, 79/183) MDR-DEC pathotypes were identified. MDR was common among enteroaggregative E. coli (EAEC) (58%, 44/76), followed by enterotoxigenic E. coli (ETEC) (44%, 17/39)) and enteroinvasive E. coli (EIEC) (30%, 7/23). Phenotypically, a total of 30 MDR-DEC pathotypes (16.4%, 30/183) were tested positive for ESBLs. Few ETEC (5.1%, 2/39) and EAEC (2.6%, 2/76) were carbapenemase producers. The predominant β-lactamase genes identified was bla(TEM) (80%, 24/30) followed by bla(CTX-M) (73%, 22/30), bla(SHV) (60%, 18/30), bla(NDM) (13%, 4/30), and bla(OXA-48) (13%, 4/30). Majority of the ß-lactamase encoding genes were detected in EAEC (50%) and ETEC (20%). Co-existence of different β-lactamase genes was found in the present study. CONCLUSION: The bla(TEM), bla(CTX-M), bla(SHV), bla(NDM), and bla(OXA-48), that are associated with serious and urgent threats globally, were detected in diarrheagenic E. coli isolates from under-five children in Ethiopia. This study also revealed the coexistence of the β-lactamase genes.