Once-daily intramuscular amikacin for outpatient treatment of lower urinary tract infections caused by extended-spectrum ß-lactamase-producing Escherichia coli in children

Abstract

Background: The rise in community-acquired urinary tract infections (UTIs) with extendedspectrum ß-lactamase (ESBL)-producing Escherichia coli strains raises the question of how to treat these infections effectively in pediatric outpatients. Amikacin has shown promising in vitro activity against ESBL-producing urinary isolates of E. coli; however, clinical data are limited. Objective: To investigate the clinical and microbiological outcomes of community-acquired lower UTIs caused by ESBL-producing E. coli treated with outpatient amikacin in children. Materials and methods: A retrospective cohort study was performed on pediatric patients aged ?2 to 18 years treated as outpatients with intramuscular amikacin (given at a dose of 15 mg/kg/day once daily) for community-acquired lower UTIs caused by ESBL-producing E. coli, between January 2015 and December 2016. Results: A total of 53 pediatric patients (38 females) were enrolled in this study. The median age was 4.7 years (range 3-12 years). All E. coli isolates were susceptible to amikacin with minimum inhibitory concentrations of ?4 mg/L. The median duration of amikacin treatment was 6 days (range 3-7 days). Favorable clinical and bacteriological responses were observed in 51 of 53 (96%) patients. Development of resistance during treatment with amikacin was seen in only 1 patient (2%), who failed to respond to amikacin treatment and developed acute pyelonephritis with bacteremia. Relapsed lower UTI after initial treatment response occurred in 1 patient (2%) 2 weeks after completion of amikacin treatment. All patients had normal serum creatinine values at baseline, and no significant nephrotoxicity or ototoxicity was observed in any of the patients. Conclusion: Our study suggests that once-daily intramuscular amikacin could be an alternative option for outpatient treatment of community-acquired lower UTIs caused by amikacinsusceptible ESBL-producing E. coli in pediatric patients with normal renal function, when there are no suitable oral antibiotics. © 2017 Polat and Kara.