Work

Whole-Genome Characterization of Pediatric Urinary E. coli Isolates from a Tertiary Care Pediatric Hospital in Guayaquil, Ecuador: Identification of the High-Risk ST1193 Clone

Year: 2026

Type: article

Abstract: Background: Escherichia coli is a leading cause of urinary tract infections (UTIs) in children, and increasing antimicrobial resistance complicates empirical treatment. However, genomic information on pediatric urinary E. coli associated with urinary tract infection in Ecuador remains limited. Objective: This exploratory study analyzed four E. coli isolates obtained from urine samples of pediatric patients at a tertiary hospital in Guayaquil, Ecuador. Methods: Whole-genome sequencing (WGS) was performed to determine sequence types (STs), serotypes, antimicrobial resistance genes (ARGs) virulence factors (VFs), and phylogenetic relationships. Results: Two isolates were assigned to the globally disseminated high-risk clone ST1193 and carried extended-spectrum β-lactamase (ESBL) genes, including blaCTX-M-27, whereas one isolate was assigned to ST162 and carried blaCTX-M-65. The remaining isolate could not be assigned to a complete ST because of missing MLST loci, but it harbored blaCTX-M-15, blaOXA-1, and blaTEM-1. Fluoroquinolone resistance-associated substitutions were detected in gyrA, parC, and parE in three isolates. The isolates shared a conserved set of VFs involved in adhesion, iron acquisition, and secretion systems. ARGs were frequently associated with insertion sequences and IncF plasmid replicons, indicating a potential contribution of mobile genetic elements (MGEs) to the dissemination of antimicrobial resistance. Conclusions: Despite the limited number of isolates, these findings provide preliminary genomic evidence of the presence of ST1193 and diverse ESBL-producing urinary E. coli lineages among pediatric patients in Guayaquil, supporting the need for expanded genomic surveillance and antimicrobial stewardship efforts at the hospital level.

Source: Antibiotics

DOI: 10.3390/antibiotics15100996