Antibiotic Resistance, Biofilm Formation and Sub-Inhibitory Hydrogen Peroxide Stimulation in Uropathogenic .

Uropathogenic (UPEC) is the most prevalent cause of urinary tract infections (UTIs). Biofilm formation and antibiotic resistance could be high among the causative agent. The purpose of this study was to determine antibiotic resistance, biofilm production, and biofilm-associated genes, and , and sub-inhibitory hydrogen peroxide (HO) stimulation in UPEC for biofilm formation. A total of 71 UPEC were collected from a tertiary care hospital in Kathmandu and subjected to identify antibiotic susceptibility using Kirby-Bauer disk diffusion. The biofilm formation was assessed using microtiter culture plate method while pellicle formation was tested by a tube method. In representative 15 isolates based on biofilm-forming ability, and were screened by conventional polymerase chain reaction, and treated with sub-lethal HO. The UPEC were found the most susceptible to meropenem (90.2%), and the least to ampicillin (11.3%) and 90.1% of them were multi-drug resistant (MDR). Most UPEC harbored biofilm-producing ability (97.2%), and could form pellicle at 37°C. Among representative 15 isolates, was detected only among 10 isolates (66.67%) while gene was present in 13 isolates (86.67%). This study revealed that level of biofilm production elevated after sub-lethal HO treatment ( = .041). These findings suggested that the pathogens are emerging as MDR. The biofilm production is high and the majority of selected strains contained and genes. Pellicle formation test was suggestive to be an alternative qualitative method to screen biofilm production in UPEC. The sub-inhibitory concentration of HO may contribute in increasing biofilm formation in UPEC.