Clinical features and treatment strategies of febrile urinary tract infection caused by extended-spectrum beta-lactamase–producing Enterobacteriaceae in children: a multicenter retrospective observational study in Japan

Objectives: The incidence of infections caused by extended-spectrum beta-lactamase (ESBL)–producing bacteria has increased. This study aimed to clarify the risk factors and treatment strategies for febrile urinary tract infection (fUTI) caused by ESBL-producing bacteria in Japanese children. Methods: A retrospective observational study was conducted in 21 hospitals among children aged <16 years diagnosed with an fUTI between 2008 and 2017. Clinical data of children with fUTI caused by ESBL-producing and non-ESBL–producing bacteria were compared. Results: Of the 2049 cases of fUTI, 147 (7.2%) were caused by ESBL-producing bacteria. Children in the ESBL group were more likely to have a history of recent antibiotic use or prophylactic antibiotic use, and experience recurrent UTIs (P <0.001) compared with those in the non-ESBL group. Of the 124 cases of fUTI due to ESBL-producing bacteria that were reviewed, 20 and 100 had concordant and discordant antibiotic use, respectively, and four had unknown antibiotic susceptibility. The median time from the start of treatment to fever resolution was 24 hours and did not differ significantly by therapy group (P = 0.39). Conclusion: ESBL-producing bacteria should be considered in children with recurrent UTIs and recent antibiotic use. Most children with fUTI experience clinical improvement regardless of the choice of antibiotic.