Detección del gen blaCTX-M grupo 1 en enterobacterales productores de betalactamasas de espectro extendido en cepas procedentes de la Clínica Santa Ana y Hospital del Río, Cuenca 2024

Abstract

Background: Extended-spectrum beta-lactamases (ESBLs) are enzymes that hydrolyze the beta-lactam ring, resulting in the main mechanism of bacterial resistance. These enzymes are encoded on plasmids and arise from mutations in the bla gene, bringing about beta-lactamase variants like Cefotaximases (CTX-M). Particularly, CTX-M has the ability to hydrolyze cefotaxime, ceftriaxone, ceftazidime, and cefepime more efficiently. Objectives: To detect the presence of the blaCTX-M group 1 gene in Enterobacterales producing extended-spectrum beta-lactamase. Methods: This is cross-sectional descriptive study. The universe included bacterial strains including Enterobacterales which produce ESBL, from Santa Ana Clinic and the Del Rio Hospital in 2024. Data was collected using registration forms and Microsoft Excel and IBM SPSS 30.0. Results: During March-August 2024, 85 ESBL producing Enterobacterales strains were isolated, in which Escherichia coli prevailed (78,8%), mainly in urine samples (64,6%), followed by Klebsiella pneumoniae (14%), Proteus mirabilis, and Morganella morganii (2,4%), mainly isolated from urine samples. The presence of the blaCTX-M group 1 gene represented 68,2%, a percentage distributed in Escherichia coli (57,6%), Klebsiella pneumoniae (9,4%), Morganella morganii (1,2%), and no presence in Proteus mirabilis. Conclusions: The detection of the blaCTX-M group 1 gene by microbiological and molecular tests allowed to determine its frequency through updated epidemiological data.