Antimicrobial Susceptibility Patterns of Community-Acquired Uropathogenic Escherichia coli, Dublin 2010-2022

Background: Escherichia coli is a common cause of urinary tract infections. Due to the increase in antimicrobial resistance (AMR) and global differences in antimicrobial susceptibility data, routine assessment of local antimicrobial susceptibility patterns is necessary to guide the selection of appropriate empiric therapy. The aim of this study was to evaluate antimicrobial susceptibility patterns of community-acquired uropathogenic Escherichia coli within a catchment area in Dublin over a 13-year period, 2010-2022. Methods All mid-stream urine samples received from local general practitioners in which there was a significant Escherichia coli bacteriuria during the study period, 2010-2022 were included in the analysis. Antimicrobial susceptibility testing was performed by disc diffusion as per the European Committee on Antimicrobial Susceptibility Testing recommendations. Results An average of 11,407 urine samples per month had significant bacteriuria; with Escherichia coli accounting for an average of 67% of those. Overall AMR rates were highest for ampicillin (53.9%), followed by trimethoprim (32.4%), gentamicin (18.6%), co-amoxiclav (16.5%), ciprofloxacin (12.3%), cephalexin (8.3%), cefpodoxime (6.8%) and nitrofurantoin (2%). While rates appeared grossly static, statistically significant reduced resistance rates were noted for co-amoxiclav (rs = -0.95; p = <0.001), cephalexin prior to 2019 (rs = -0.783; p = 0.013) and trimethoprim (rs = -0.639; p = 0.019); with a statistically significant increase in non-susceptibility to cefpodoxime (rs = 0.802; p = 0.001). Conclusions In order to generate efficient empiric antimicrobial prescribing guidelines, knowledge of region-specific contemporaneous antimicrobial susceptibility patterns is pivotal. Our findings support the use of nitrofurantoin or cephalexin as empiric antimicrobial therapy within our setting.