Intravenous Antibiotic Susceptibility for Urinary Tract Infection Prior to Emergency Department Discharge

Background: Urinary tract infection (UTI) is a common infectious disease managed in the emergency department (ED). Patients may be initially treated with an intravenous (IV) antibiotic and subsequently discharged with an oral antibiotic regimen. Objective: The purpose of this study was to determine whether the current Infectious Diseases Society of America guideline recommendation for an initial dose of long-acting IV antibiotic for treatment of UTI when the prevalence of fluoroquinolone resistance exceeds 10% improves the likelihood of providing in vitro susceptibility to the isolated uropathogen. Methods: This was a retrospective study of patients in ED presenting between May 2009 and August 2018 who received treatment for UTI. The primary outcome was susceptibility of uropathogen to the IV antibiotic administered. Secondary outcomes included susceptibility to the oral antibiotic regimen prescribed at discharge, repeat health care visit within 30 days related to UTI follow-up, adverse events (AEs) associated with antibiotic use, and identification of risk factors associated with pathogen resistance. Results: A total of 255 patients were included for analysis. Of these patients, 230 (90.2%) had pathogens susceptible to the administered IV antibiotic. The oral regimen susceptibility was 81.6% with 29 patients returning for UTI follow-up and 4 patients reporting AEs related to antibiotic use. Men and long-term care facility residents were more likely to have resistant uropathogens. Conclusion: Administration of a long-acting IV antibiotic for treatment of UTI prior to ED discharge is recommended when the fluoroquinolone resistance rate exceeds 10% to improve in vitro susceptibility coverage.