Molecular Characterization of Extended-Spectrum Beta-Lactamase-Producing Escherichia coli from Community Fecal...

This study aimed to determine beta-lactamase genes, clonal relationships, and the prevalence of the E.coli sequence type 131 (ST131) clone in extended-spectrum beta-lactamase (ESBL)-producing E.coli (ESBL-Ec) strains isolated from community fecal samples.

A total of 161 fecal samples were collected from healthy individuals and outpatients at Sivas Cumhuriyet University Hospital. ESBL-Ec isolates obtained from these samples were analyzed. Antimicrobial susceptibility was determined by the disc diffusion method following EUCAST guidelines. The presence of blaTEM, blaSHV, blaCTX-M, blaOXA, blaPER, blaVEB, and blaGES genes was investigated by multiplex PCR. The ST131 clone was detected by PCR and Multi Locus Sequence Typing analyses. Clonal relatedness among ESBL-Ec strains was evaluated using ERIC-PCR.

The fecal ESBL-Ec carriage rate was 31.05%. Resistance rates to ciprofloxacin, trimethoprim-sulfamethoxazole, gentamicin, amikacin, and ertapenem were 38%, 58%, 14%, 6%, and 4%, respectively. ESBL genes were detected at rates of blaTEM 82%, blaCTX-M 68%, and blaOXA 10%. ESBL-Ec isolates were grouped into 15 clusters, and 5 (10%) of 50 isolates were identified as the ST131 clone.

This first study in Sivas, Türkiye, shows a high fecal carriage rate of ESBL-Ec and the presence of the E.coli ST131 clone.