Detection of Antimicrobial Susceptibility and Integrons Among Extended-spectrum β-lactamase Producing Uropathogenic Escherichia coli Isolates in Southwestern Iran.

Abstract

Urinary tract infections (UTIs) are one of the most prevalent infectious diseases and can lead to a high rate of morbidity and mortality. The emergence of multiple-drug resistant strains, particularly extended-spectrum beta-lactamases (ESBLs) producing strains, has become a global healthcare concern. Our study sought to investigate the antimicrobial resistance pattern and presence of integrons and fimH determinants among uropathogenic Escherichia coli (UPEC) isolates obtained from hospitalized Iranian patients. This cross-sectional study was performed on 121 E. coli isolates recovered from patients with clinical symptoms of UTIs, referred to Shiraz Nemazee Hospital, in 2016-17. The isolates were identified by standard microbiologic tests and confirmed by API 20E strip. Antimicrobial susceptibility testing was determined using the disk diffusion method. The presence of fimH and classes 1-3 integron encoding genes was determined using the polymerase chain reaction. Ampicillin (9.1%) and nalidixic acid (19.0%) showed the lowest level of antibiotic susceptibility. The highest level of susceptibility was toward imipenem (77.7%). The rate of ESBL-producing isolates was 42.1%. There was a significant association between production of ESBLs and higher antibiotic resistance in the tested isolates. Of the investigated virulence and resistance genes, fimH, intI1, and intI2 were positive in 98.3%, 59.5%, and 7.4% of isolates, respectively. The remarkable rate of ESBL-producing UPEC isolates accompanied with the presence of integrons suggest the necessity of restricted infection control policies to prevent further dissemination of resistant strains.