A Relationship Between O-Serotype, Antibiotic Susceptibility and Biofilm Formation in Uropathogenic Escherichia coli.

ABSTRACT

Uropathogenic Escherichia coli (UPEC) is a well-known pathogen that has perturbed the medical scenario because of its resistance to diverse therapeutic drugs and its ability to form a biofilm. Different O-serogroups are the prevalent cause of urinary tract infections (UTIs) along with their ability to form a biofilm. The present research aimed to assess antibiotic susceptibility, biofilm formation, and serotyping of UPEC isolates in conjunction with the demographic data. Antibiotic susceptibility was determined using the Kirby-Bauer method and biofilm formation was assessed phenotypically and at the molecular level. Serotyping was performed by multiplex PCR. A significant proportion of the total of 120 UPECs was isolated from women (p < 0.05). Most isolates were resistant to cefotaxime, ceftazidime, and tetracycline, but maintained their sensitivity to imipenem. O25, O15, O8, and O75 were the most commonly detected serogroups. Moreover, O25, O15, and O8 were the highest biofilm-producing serogroups among the UPEC isolates. Serogroups O75 and O21 were significantly associated with diabetic patients and subjects with renal disease, respectively (p < 0.05). Overall, our results show that UTI incidence in women should be a subject of concern. The high prevalence of the O25 serogroup associated with a specific antibiotic profile and a high percentage of biofilm formation suggests a close relation between serogroups and characteristic features of UPEC isolates.