Epidemiology of urinary tract infection in adults caused by extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae - a case-control study from Qatar

Background: Community-acquired urinary tract infection (UTI) is the most common infection caused by extended -spectrum beta-lactamase (ESBL)-producing organisms. Aim: to estimate the prevalence of ESBL-UTI in adults and to identify potential risk factors that may predispose to ESBL-UTI. Methods: A retrospective study involving adult patients with UTI caused by ESBL-producing organisms was undertaken. Patients with UTI caused by non-ESBL-producing organisms represented the control group. Results: In total, 1100 UTI isolates were included in the study, 277 of which were ESBL positive. The prevalence rate was 25.2%. The mean age of patients was 55.87 years. On univariate analysis, prior history of UTI or ESBL-UTI, invasive urological procedure within preceding 3 months, hospital admission within preceding 3 months, and exposure to antibiotics were found to be significant risk factors for ESBL-UTI. On multi-variate analysis, use of cephalosporins [adjusted odds ratio (OR) 1.61, P = 0.048], previous ESBL-UTI (adjusted OR 2.67, P < 0.001), and invasive urological procedure in the preceding year (adjusted OR 1.61, P = 0.022) were found to be independent risk factors for ESBL-UTI. Conclusions: In Qatar, the prevalence of ESBL-UTI in adults is modest. Recent exposure to antibiotics, previous ESBL-UTI and invasive urological procedures were found to be independent risk factors for ESBL-UTI.