Caracterização de Escherichia coli produtoras de beta-lactamases de espectro estendido isoladas de bezerros

Abstract

Antimicrobial resistance is not a recent phenomenon, but it is a critical problem of world public health. The production of extended spectrum beta-lactamase (ESBL) by the Enterobacteriales group is the increasingly cited bacterial resistance mechanism in recent decades, present in the human-amimal-environment interface. This study aimed to verify in fecal calf samples, the presence of ESBL-producing Escherichia coli strains, identifying blaCTX-M-2, blaCTX-M-8, blaCTX-M-15, blaSHV and blaTEM by the Polymerase Chain Reaction method (PCR) and phenotypically by the approach disc screening method. It also was an aim of a rapid identification method for multiresistant E. coli isolates, using the Fourier Transform Infrared Spectroscopy (FTIR) method. Diarrheagenic E. coli isolates, and eight isolates were subjected to PCR, the presence of at least one of the genes mentioned in 35.6% of the total (n = 74). A distributed genes from positive samples occurred as follows: 3.84% were positive for blaCTX-M-2, 5.28% for blaSHV gene and 29.3% for the blaTEM gene. The blaCTX-M-15 and blaCTX-M-8 genes were not observed in the study. Regarding susceptibility to antimicrobials, the samples showed high resistance rates to the beta-lactam group, as well as for tetracycline (80%), in which 50.9% (106/208) were phenotypically multi-resistant, showing that strains carriers with strains bacterial with ESBL enzyme can be a constant dissemination reservoir. Additionally, 40 isolates of E. coli diarrheagenic multiresistant were selected to be measured in the FTIR, with spectra harvested from 4000 to 700 cm-1, 3000 to 2800 cm-1, and 1800 to 800 cm-1. The FTIR method for machine learning was able to identify the isolates of E. coli diarrheagenic multi-resistant with 70% accuracy in validation tests, demonstrating that the FTIR could be a screening tool for bacteriological and diagnostic studies.