Study on the presence of resistant diarrheagenic pathotypes in Escherichia coli isolated from patients with urinary tract infection.

AIM: This article aimed to analyze the diarrheagenic potential of E. coli isolated from urinary tract infection (UTI) and to recognize the presence of antibiotic resistance genes.
BACKGROUND: The marked genome plasticity of Escherichia coli has allowed the emergence of resistant pathogenic strains displaying an unusual arrangement of genes.
METHODS: In this cross-sectional study, 110 E. coli were isolated from patients with the symptoms of UTI in Sanandaj, west of Iran between July and September - 2015. The isolates were examined by the disk diffusion method for antibiotic susceptibility test and by polymerase chain reaction for the presence of genes characteristic of diarrheagenic E. coli (DEC), Uropathogenic E. coli (UPEC) virulence genes, extended-spectrum β-lactamase bla CTX-M and plasmid-mediated quinolone resistance determinants, qnrA, qnrB, and qnrS.
RESULTS: The most and the least effective antibiotics were nitrofurantoin and cefotaxime (96.4% and 27.3% sensitivity, respectively). Of the 110 UTI isolates, 57.3% carried diarrheagenic genes. The bundle-forming pilus bfpA was the most prevalent diarrheagenic gene (39.1%). The most commonly detected DEC pathotype was enterotoxigenic E. coli (-ETEC, 12.7%). All the pathotypes carried the bla CTX-M and qnr. The -UPEC hly hemolysin and pap adhesin genes were mainly detected among ETEC isolates.
CONCLUSION: Our results indicated the presence of resistant diarrheagenic pathotypes in UTI-associated E. coli. Such isolates may have the capacity of causing both extraintestinal and intestinal infections. Based on our knowledge, this is the first report of the presence of qnr in ETEC from urine. ©2019 RIGLD, Research Institute for Gastroenterology and Liver Diseases.