Abstract

Introduction. Urinary tract infection (UTI) is the most common diagnosed bacterial infection in the world and its most frequent causal agent is the Escherichia coli (E. coli), a bacterium that has gained importance due to its ability to produce extended-spectrum beta-lactamase (ESBL), which makes treatment difficult and leads to more frequent recurrent infections including their complications, and even more in immunocompromised patients. Objective. To identify patients with UTI caused by ESBL-producing E. coli and evaluate their antibacterial and molecular spectrum. Material and methods. A longitudinal and prospective study performed with urinary samples from 53 patients of Caja Nacional de Salud in La Paz, Bolivia. In 72% of the samples, E. coli was isolated as a causative agent, of these, 35 had ESBL phenotype, sensitive to imipenem, gentamicin and nitrofurantoin (100%) and amikacin (94%). Phenotyping assays reported a predominance of PhP-2 type and phylogenetic assays (PCR and sequencing) identified a predominance of bla CTX-M-15 associated with bla TEM-1. Conclusion. Early recognition and effective treatment of UTI produced by multiresistant ESBL-producing strains of E. coli should be recognized based on the evidence obtained.