English

Abstract

BACKGROUND Urinary tract infections are some of the most common community-acquired as well as nosocomial infections with E. coli being the most common pathogen. There is increased antimicrobial resistance among bacteria worldwide. One of the important mechanisms of resistance and virulence of bacteria is biofilm formation. This study was conducted to find out the association between antibiotic resistance pattern and biofilm formation in E. coli in non-catheterised patients of UTI in a tertiary care hospital. We further wanted to determine the association between the ability of E. coli to form biofilm and their ability to produce extended-spectrum beta-lactamases (ESBLs) and carbapenemase in non-catheterised patients. METHODS Urine samples collected from 300 non-catheterised patients who had symptoms of UTI were inoculated into MacConkey’s agar and blood agar media. Then identification and antibiotic susceptibility tests were done. Phenotypic detection of ESBL production was done by double disc diffusion test and carbapenemase production was done by mCIM (modified carbapenem inactivation method) and eCIM (EDTA carbapenem inactivation method) tests according to Clinical and Laboratory Standards Institute (CLSI) 2019 guideline. Biofilm detection was done by Congo red agar (CRA) method. RESULTS Out of 78 isolates E. coli were the commonest (61.5 %) isolate. Out of 48 E. coli isolates from non-catheterised UTI patients, 26 (54.1%) were biofilm producers. Antibiotic sensitivity pattern among the E. coli isolates showed the highest susceptibility of the strains to amikacin, whereas the least susceptibility was for amoxicillin. Out of 48 E. coli, 20 (41.6 %) were ESBL producers, 16 (33.33 %) E. coli were carbapenemase producers. Significant association was found between ESBL and biofilm production. However, no statistical significance was found between the association of carbapenemase production and biofilm formation. CONCLUSIONS Uropathogenic E. coli is not an uncommon pathogen for biofilm formation even in non-catheterised patients. The antibiotic-resistance rate was higher among biofilm producing E. coli isolates. The biofilm forming ability was found to be significantly higher among ESBL producing strains but was not statistically significant for carbapenemase producing strains of E. coli. KEYWORDS Biofilm, Uropathogen, Congo Red Agar (CRA) Method, UTI, ESBL, Carbapenemase