Characterization of biofilm-forming Escherichia coli in canine urinary tract infections: Phenotypic and genotypic insights

Abstract

Uro-pathogenic Escherichia coli (UPEC) is responsible for causing urinary tract infections in canines. The capacity to form biofilms and employ diverse virulence factors enables UPEC to endure within the uroepithelium, causing chronic and persistent infections. Unintended antimicrobial usage, whether for therapeutic purposes or otherwise, exposes bacterial pathogens to varying concentrations of antimicrobial drugs, promoting the emergence and proliferation of resistant bacteria. To characterize UPEC from urinary tract infections, samples (n=51) were collected and subjected to microbial isolation using MacConkey Lactose agar (MLA) and Eosin Methylene Blue agar (EMB), which led to the isolation of 19 E. coli isolates, confirmed using uspA gene amplification. These isolates were characterized using a set of three virulence genes namely aer, pap and cnf1. Furthermore, all the 19 isolates were subjected to microtiter plate assay for biofilm detection and the result showed that biofilm formation was observed in both LB and TSB media and at 72h incubation time indicated that in LB media, 2 (10.5%) isolates were strong biofilm producers, 3 (15.7%) isolates were moderate biofilm producers, 7 (36.8%) isolates were weak biofilm producers and 7 (36.8%) isolates had not produced any biofilm while in TSB media (72h), 4 (21%) isolates were strong biofilm producers, 9 (47.3%) isolates were moderate biofilm producers, 3 (15.7%) isolates were weak biofilm producers and 3 (15.7%) isolates had not produced any biofilm. Antimicrobial sensitivity test using Bauer-Kirby revealed that isolates were found maximum resistant to Cephalexin, Ciprofloxacin, Metronidazole, Ampicillin, Penicillin G, Tetracycline while susceptible to Chloramphenicol, Co-trimoxazole, Imipenem, Meropenem, Gentamicin and Amikacin. This study demonstrates the presence of UPEC capable of forming biofilms in canines suffering from urinary tract infections. Further research is essential to elucidate the role of biofilms in the pathogenesis of UPEC and their implications for antimicrobial resistance.