Biofilm formation, antimicrobial susceptibility, serogroups and virulence genes of uropathogenic E. coli isolated from clinical samples in Iran

Antimicrob Resist Infect Control. 2016 Apr 1:5:11. doi: 10.1186/s13756-016-0109-4. eCollection 2016.

Abstract

Background: Uropathogenic Escherichia coli O- Serogroups with their virulence factors are the most prevalent causes of UTIs. The present research performed to track common uropathogenic E.coli serogroups, antibiotic resistance pattern of strains and prevalence of virulence genes in isolations having the ability to constitute biofilm.

Methods: In this research 130 E.coli isolation from patients having UTI symptoms were collected and antimicrobial resistance pattern was performed by Kirby-Bauer method. Polymerase chain reaction was done using primer pairs to identify common serogroups of uropathogenic E.coli and studying virulence genes in isolations creating biofilm.

Results: Among 130 E.coli isolates, 80 (61.53 %) were able to make biofilm that 15 isolates (18.75 %) indicated strong reaction, 20 (25 %) of medium and 45 (56.25 %) of weak biofilm reaction. Among isolations creating biofilm, the highest resistance reported to Ampicillin (87.5 %) and the lowest to Nitrofurantoin (3.75 %). The frequency of fimH, pap, sfa and afa genes in isolations having the ability to create strong biofilm reported 93.33 %, 86.66 %, 86.66 % and 66.66 %, respectively.

Conclusions: The findings indicated the importance of virulence genes in serogroups producing uropathogenic E.coli biofilm. It is recommended that strains producing biofilm before antibiotic use should be studied.

Keywords: Antibiotic resistance pattern; Biofilm; Urinary Tract Infection; Uropathogenic E. coli; Virulence genes.