Abstract
BACKGROUND: Pediatric urinary tract infection (UTI) is associated with diagnostic and therapeutic challenges. OBJECTIVE: To determine the least-broad-spectrum oral antibiotic that would cover 80% of pathogens from lower (afebrile) and upper (febrile) UTIs in a Canadian pediatric emergency department (ED). METHODS: This retrospective case series involved children discharged from the ED between September 2020 and February 2021 with a diagnosis of UTI and collection of a sample for urinalysis that had growth on culture. RESULTS: Of 188 patients who met the inclusion criteria, 184 (97.9%) were discharged on antibiotics. Culture results indicated a UTI in 170 cases (92.4% of those discharged on antibiotics). The 95 urinary isolates from lower UTIs were susceptible to cephalexin (n = 81, 85.3%), cefixime (n = 78, 82.1%), nitrofurantoin (n = 76, 80.0%), trimethoprim-sulfamethoxazole (TMP-SMX) (n = 64, 67.4%), and amoxicillin (n = 55, 57.9%). The 75 urinary isolates from upper UTIs were susceptible to cefixime (n = 71, 94.7%), TMP-SMX (n = 57, 76.0%), and amoxicillin (n = 48, 64.0%). The mean prescribed duration of antibiotic therapy was 8.3 days for patients with a lower UTI and 9.1 days for those with an upper UTI (mean difference 0.80 days, 95% confidence interval 0.05-1.54). CONCLUSIONS: Empiric treatment with cephalexin or nitrofurantoin would have been successful for almost all lower UTIs. More complete reporting of cephalexin minimal inhibitory concentrations might have allowed use of this drug for most upper UTIs. Although there was a trend toward shorter duration of therapy for lower versus upper UTI, lower UTIs were always treated for longer than recommended by current guidelines.