Distribution of Ciprofloxacin-Resistance Genes Among St131 and Non-St131 Clones of Escherichia Coli Isolates With Esbl Phenotypes Isolated From Women With Urinary Tract Infection



Rasoulinasab M¹ ; Shahcheraghi F¹ ; Feizabadi MM^{2, 3} ; Nikmanesh B⁴ ; Hajihasani A¹ ; Aslani MM¹
Source: Iranian Journal of Microbiology Published:2021

Abstract

Background and Objectives: Escherichia coli (E. coli) sequence type 131 (ST131) is associated with extended-spectrum beta-lactamase (ESBL) production and fluoroquinolone resistance. This study aimed to investigate the prevalence of ST131, ESBL, and plasmid-mediated quinolone resistance (PMQR) genes in the ciprofloxacin-resistant (CIPR) and ESBL producers from women with UTI. Materials and Methods: The CIP-resistant ESBL producing (CIPR/ESBL+) E. coli isolates were screened for ST131-by specific PCR of mdh and gyrB. The ESBL and PMQR genes were screened by single PCR. The ST131 and non-ST131 isolates were selected to determine the mutations of gyrA and parC using PCR and sequencing, and also their genetic background by the Pasteur-MLST scheme. Results: Overall, 55% (33/60) CIPR/ESBL+ isolates were identified as ST131 (94% O25b-ST131). Resistance rate to ampi-cillin-sulbactam (70%), aztreonam (97%) and gentamicin (61%), the prevalence of aac(6′)-Ib-cr (66%), blaCTX-M-15 (82%), the profile of qnrS+aac(6′)-Ib-cr (30%), and the double mutation in the parC was significantly higher in ST131 than non-ST131 isolates. The coexistence of PMQR and ESBL genes was found in more than 50% of ST131 and non-ST131 isolates. ST131 isolates differentiated into PST43 and PST506. Conclusion: Management of women with UTI caused by the CIPR/ESBL+ isolates (ST131) co-harbored PMQR, ESBL, and chromosomal mutations, is important for their effective therapy. © 2021 The Authors. Published by Tehran University of Medical Sciences.