Phenotypic and genotypic characterization of virulence factors in carbapenemase-producing uropathogenic Escherichia coli strains

Ramos-Nolazco G.A.; Coral-Clavijo S.A.; Egoavil-Rosales R.D.; Gonzales-Escalante E. · Anales de la Facultad de Medicina (2025) · DOI: 10.15381/anales.v86i4.31563

Resumen

Introduction. Uropathogenic Escherichia coli (UPEC) is the leading cause of urinary tract infections (UTIs). Its carbapenem-resistant form (UPEC-rC) harbors specific virulence factors that further limit therapeutic options. Objective. Identify virulence factors in UPEC-rC isolates recovered from urine samples of patients with UTIs in Lima, Peru. Methods. We conducted a descriptive observational study including 58 UPEC-rC isolates. Virulence factors were analyzed in the laboratory: phenotypically (hemolysin on blood agar, P fimbriae by erythrocyte hemagglutination and biofilms production using the microtiter plate method) and genotypically (α-hly, papGII, aer, cnf1, sfa/focDE) by PCR. Results. 28 out of 58 isolates exhibited at least one virulence factor. Genotypically, aer gene was the most frequent (34,5%), while phenotypically, biofilm formation predominated (17,2%). Conclusion. The frequency of aer gene and biofilm production suggests a possible relationship between carbapenem resistance and the attenuation of pathogenic mechanisms.

Instituciones: Universidad de Piura