Evaluation of the Virulence Genes in Quinolone and Fluoroquinolones- resistant Uropathogenic Escherichia coli Isolates

 Uropathogenic Escherichia coli (UPEC) is the most prevalent causative agent of urinary tract infections (UTIs) in both community and hospital settings. Annually about 150 million people globally develop UTIs, resulting in increased healthcare costs. The current study examined the identification and the frequency distribution of virulence factors among fluoroquinolones-resistant (FQs-R) and fluoroquinolones-susceptible (FQs-S) UPEC strains in Hamadan hospitals, west of Iran.

 One hundred-seventy urine samples were collected consecutively from inpatients at three hospitals in Hamadan from March to September 2018. The UPEC isolates were identified using biochemical tests and polymerase chain reaction (PCR). The disk diffusion and the broth microdilution methods determined the antimicrobial susceptibility and the minimum inhibitory concentration (MIC) of Ciprofloxacin. The multiplex-PCR method investigated the prevalence of pap, aer, and hly genes.

Among 170 urine samples collected from inpatients, E. coli was the most common isolate, with a frequency of 125 (73.5%). Resistance to Nalidixic acid and fluoroquinolones, including Ciprofloxacin, Norfloxacin, and Ofloxacin, was detected in 88.8%, 71.2%, 70.4%, and 68.8% of UPEC isolates, respectively. The prevalence of hly and pap genes in FQs-R strains was significantly lower than in FQs-S strains.

 The high-level antibiotic resistance to quinolones & fluoroquinolones and heterogeneity of virulence genes among clinical UPEC isolates need strong attention.