Antimicrobial Resistance Trends and Molecular Mechanisms of Extended-Spectrum Beta-Lactamase (ESBL) Production in Pediatric Diarrheagenic Escherichia coli

International Journal of Medicine and Medical Sciences | Vol. 11, No. 5, May 2021 | pp. 33–40

DOI: 10.46882/2021/IJMMS/110033

Original Research Article

Antimicrobial Resistance Trends and Molecular Mechanisms of Extended-Spectrum Beta-Lactamase (ESBL) Production in Pediatric Diarrheagenic Escherichia coli

Elizabeth A. Cole¹, Moses Z. Tarawallie², Victoria N. Okoye¹*

¹Department of Medical Microbiology, College of Medicine and Allied Health Sciences, University of Sierra Leone, Freetown, Sierra Leone.

²Department of Paediatrics, Connaught Hospital, Freetown, Sierra Leone.

Abstract:

The emergence of Extended-Spectrum Beta-Lactamase (ESBL)-producing enteric bacteria in pediatric populations complicates clinical management and limits oral antibiotic options. This prospective cross-sectional study evaluated the prevalence, susceptibility trends, and molecular genotypes of ESBL-producing Escherichia coli isolated from stool samples of children under five years old presenting with acute diarrhea. Stool specimens from 300 children were cultured on selective media, and E. coli isolates were identified using standard biochemical profiles. Phenotypic confirmation of ESBL production was performed using the double-disk synergy test, and underlying genotypes (blaCTX-M, blaTEM, and blaSHV genes) were screened via multiplex PCR. The overall isolation rate of diarrheagenic E. coli was 38.0% (114/300). Among these isolates, the prevalence of phenotypically confirmed ESBL producers was 24.6% (28/114). Antibiogram screening showed high co-resistance rates among ESBL strains to trimethoprim-sulfamethoxazole (92.8%), ciprofloxacin (64.3%), and gentamicin (57.1%); however, all strains remained completely susceptible to amikacin and meropenem (100%). Molecular analysis revealed that the blaCTX-M gene was the most common genotype (78.6%), followed by blaTEM (53.6%) and blaSHV (17.8%), with multiple resistance genes detected in 35.7% of the isolates. Risk factor analysis indicated that previous over-the-counter antibiotic use (OR = 3.8, 95% CI = 1.9–7.6, p < 0.01) was strongly associated with ESBL-producing infections. ESBL-producing E. coli represents a significant cause of pediatric diarrhea, showing high resistance to common oral drugs. This highlights the need for stronger oversight of over-the-counter antibiotic sales and routine laboratory testing for pediatric gastrointestinal infections.

Keywords: Diarrheagenic Escherichia coli, Pediatric Diarrhea, Extended-Spectrum Beta-Lactamase, blaCTX-M gene, Drug Resistance, Antimicrobial Stewardship

Manuscript Timeline: Received: January 10, 2021; Revised: February 20, 2021; Accepted: March 15, 2021; Published: May 12, 2021.

Citation: Cole EA, Tarawallie MZ, Okoye VN. Antimicrobial Resistance Trends and Molecular Mechanisms of Extended-Spectrum Beta-Lactamase (ESBL) Production in Pediatric Diarrheagenic Escherichia coli. International Journal of Medicine and Medical Sciences, 2021, 11(5): 33–40. DOI: 10.46882/2021/IJMMS/110033

Subscribe to read the full article: https://internationalscholarsjournals.org/subscribe-to-read