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

Abstract

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 multidrugresistant (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-facilitybased 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. ßlactamase 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 βlactamase genes.

Antimicrobial Susceptibility and Characterization of Extended-Spectrum β-Lactamase-Producing Escherichia coli Isolated from Stools of Primary Healthcare Patients in Ethiopia

“…These higher rates of the bla CTX-M-15 gene may be associated with incompatibility group FII conjugative plasmids which carry this gene and play a great role in the spread and acquisition of resistance genes in E. coli [48]. In contrast to the present study, bla TEM was found to be the predominant β-lactamase gene in a study with children under five years of age in Ethiopia [49] and in diarrheic patients in Ghana [50]. Several variants of the bla CTX-M and bla TEM genes have been identified on both plasmids and chromosomes [9,51].…”