Discordant antibiotic therapy and length of stay in children hospitalized for urinary tract infection.

BACKGROUND Urinary tract infections (UTIs) are a common reason for pediatric hospitalizations. OBJECTIVE To determine the effect of discordant antibiotic therapy (in vitro nonsusceptibility of the uropathogen to initial antibiotic) on clinical outcomes for children hospitalized for UTI. DESIGN/SETTING Multicenter retrospective cohort study in children aged 3 days to 18 years, hospitalized at 5 children's hospitals with a laboratory-confirmed UTI. Data were obtained from medical records and the Pediatric Hospital Information System (PHIS) database. PARTICIPANTS Patients with laboratory-confirmed UTI. MAIN EXPOSURE Discordant antibiotic therapy. MEASUREMENTS Length of stay and fever duration. Covariates included age, sex, insurance, race, vesicoureteral reflux, antibiotic prophylaxis, genitourinary abnormality, and chronic care conditions. RESULTS The median age of the 216 patients was 2.46 years (interquartile range [IQR]: 0.27, 8.89) and 25% were male. The most common causative organisms were E. coli and Klebsiella species. Discordant therapy occurred in 10% of cases and most commonly in cultures positive for Klebsiella species, Enterobacter species, and mixed organisms. In adjusted analyses, discordant therapy was associated with a 1.8 day (95% confidence interval [CI]: 1.5, 2.1) longer length of stay [LOS], but not with fever duration. CONCLUSIONS Discordant antibiotic therapy for UTI is common and associated with longer hospitalizations. Further research is needed to understand the clinical factors contributing to the increased LOS and to inform decisions for empiric antibiotic selection in children with UTIs.