Molecular characteristics, antimicrobial resistance profiles, and antibiotic resistance determinants in uropathogenic fluoroquinolone resistant-Escherichia coli isolates

Abstract

The concern about multidrug resistance (MDR) in the bacterial pathogen is significant. The antimicrobial susceptibility testing performed in forty Escherichia coli isolates responsible for urinary tract infections (UTIs) to following antibiotics: ceftazidime, cefotaxime, ceftriaxone, aztreonam, co-trimoxazole, gentamicin, amikacin, nitrofurantoin, tobramycin, ciprofloxacin, and nalidixic acid performed by disk diffusion method. The presence of resistance sul1, aacC1, aadB, aphA6, qnrA, qnrB, qnrS, and ESBL genes were investigated in clinical isolates by PCR-based sequencing assay. Molecular fingerprinting of UTI isolates characterized by Pulsed-Field Gel Electrophoresis for clonal distribution and determined of predominant pulsotypes. The highest and least active agents against uropathogenic E. coli (UPEC) isolates were ciprofloxacin (100%), and tobramycin (7.5%). Fifty-percent (20/40) of the UPEC isolates were identified as ESBL-producers by phenotype. The most prevalent ESBL genes were related to bla TEM (100%; 20/20). The presence of sul1, aadB, qnrB, and qnrS genes detected in 67.5% (n = 27), 5% (n = 2), 47.5% (n = 19), and 2.5% (n = 1) of E. coli isolates, respectively. None of isolates harbor of aacC1, aphA6, and qnrA genes. The results of molecular characterizations confirmed that 31 pulsotypes found among 40 UPEC isolates. Of 31 pulsotypes, 26 types were unique and five types found in more than one isolate. Only two isolates (2/40) were not typeable. A high prevalence of plasmid-mediated quinolone resistance and ESBL genes in E. coli detected in urine samples. Data in this study suggested that these multiple pulsotypes patterns showed no clonal association between UPEC isolates.