Phenotypic and Genotypic Detection of CTX-M, SHV, and TEM Extended-Spectrum β-Lactamases in Community Clinical Isolates from Tegucigalpa, Honduras

Abstract

The global increase in infections caused by extended-spectrum β-lactamase (ESBL)-producing bacteria constitutes a serious public health threat, as it compromises the effectiveness of available antibiotics and leads to higher healthcare costs. Although historically these infections were primarily associated with hospital settings, over the past decade their spread in the community has reached concerning levels, especially in developing countries, where surveillance and control systems are limited. In this context, generating scientific evidence in community settings is a priority, where inappropriate prescription and indiscriminate use of antibiotics favor the selection and dissemination of resistant strains. Phenotypic and genotypic characterization of resistance mechanisms is essential to guide public policies related to antimicrobial access regulation and the implementation of educational programs targeting both the general population and healthcare personnel. The present study aimed to detect ESBL-encoding genes (blaCTX-M, blaTEM, and blaSHV) in Gram-negative bacteria isolated from community patients in Tegucigalpa, Honduras, during the period from September 2018 to September 2019. Clinical samples were analyzed using phenotypic double-disk synergy test, and the presence of ESBL genes was confirmed by endpoint PCR. A significant proportion of ESBL-producing strains was identified, with blaCTX-M being the most frequent gene, followed by blaTEM and blaSHV. These findings highlight the emergence of multidrug-resistant Enterobacteriaceae in the Honduran community, emphasizing the urgent need to strengthen microbiological surveillance, optimize antimicrobial prescribing policies, and develop effective containment strategies to mitigate the spread of resistance.