Detection of Multidrug-resistant Extended-spectrum Beta-lactamase-producing Enterobacteria from Community Infections in the city of Reynosa, Tamaulipas Mexico

Abstract Production of extended spectrum beta-lactamases (ESBL) is one of the main problems related to antimicrobial resistance worldwide, with the CTX-M, TEM and SHV types standing out as the most prevalent. These enzymes are usually related to plasmids which facilitates their horizontal genetic transmission. In the northeast region of Tamaulipas their clinical prevalence is unknown. Therefore, the aim of this work was to define the molecular epidemiology of ESBL-producing Enterobacteriaceae in clinical strains collected in Reynosa Tamaulipas, Mexico. A selection of 123 Enterobacteriaceae strains from different clinical patients were collected from August 2018 to December 2019. These strains were phenotypically identified by double disk synergy tests (DDST) and subsequently subjected to polymerase chain reaction for the detection and amplification of the blaTEM, blaSHV, blaCTX−M−1, blaCTX−M−2, blaCTX−M−9 and blaCTX−M−8/25 genes. Lastly, antimicrobial resistance profiles were determined by plate diffusion method and their capacity to transfer this sort of resistance by conjugation was assessed. Our results showed a prevalence of 48.78% (60/123) of ESBL-producing enterobacteria, with the blaTEM and blaCTX−M−1 genes most commonly detected in 76.67% (46/60) and 58.33% (35/60), respectively. Additionally, a 68.33% (41/60) of these ESBL-producing Enterobacteriaceae were multidrug-resistant, while 51.67% (31/60) were able to transfer some genes related to ESBL production, being blaCTX−M−1 the most common. This is the first study in the region that evaluates ESBL production in clinical Enterobacteriaceae strains, as well as the content of genes related to this phenotype and the ability to transfer this type of antimicrobial resistance.