Evaluation of pathogenicity islands in uropathogenic Escherichia coli isolated from patients with urinary catheters

Abstract

Introduction: Uropathogenic Escherichia coli (UPEC), an important causative agent of urinary tract infections (UTIs), carries virulence factors which are clustered on pathogenicity islands (PAIs). The goal of this study was to characterize the PAIs among the UPEC isolated from patients with urinary catheters.

Methodology: A descriptive cross-sectional study was designed and from December 2014 to April 2015, 78 non-duplicate E. coli were collected from hospitalized patients with UTIs, including patients with and without indwelling urinary catheters. Two multiplex polymerase chain reaction (PCR) assays were performed to evaluate the presence of the eight most studied PAIs (I ₅₃₆, II ₅₃₆, III ₅₃₆, IV₅₃₆, I _CFT073, II _CFT073, PAI I_J96, and PAI II_J96).

Results: Of 78 patients with a UTI 31 (39.7%) used indwelling catheters. Of these 31 patients, 27 (87.1%) carried PAIs markers, including 25 (80.6%) PAI IV₅₃₆, 12 (38.7%) PAI I_CFT073, 6 (19.4%) PAI II_CFT073, 6 (19.4%) PAI III₅₃₆ and 3 (9.7%) PAI II₅₃₆. PAI I₅₃₆, PAI I_J96, and PAI II_J96 were not detected in the UPEC strains.

Conclusions: The findings of this study revealed that the frequency of PAI markers in UPEC isolates from patients with indwelling urinary catheters was high. The rate of multiple PAIs carriage was notable among those patients, suggesting that UPEC strains that colonize the indwelling urinary catheters have the potential to cause complicated urinary infections. PAI I_CFT073, which was found in association with pyelonephritis, prostatitis, and sepsis, could be considered as a target for medical interventions.