Outcomes associated with initial narrow-spectrum versus broad-spectrum antibiotics in children hospitalized with urinary tract infections.

We identified 10,740 hospitalizations for UTI across 39 hospitals. Approximately 5% of encounters demonstrated initial narrow-spectrum antibiotics, with hospital-level narrow-spectrum use ranging from <1% to 25%. Approximately 80% of hospital antibiograms demonstrated >80% Escherichia coli susceptibility to cefazolin. In adjusted models, those who received initial narrow-spectrum antibiotics had shorter LOS (narrow-spectrum: 33.1 [95% confidence interval; CI]: 30.8-35.4] h vs. broad-spectrum: 46.1 [95% CI: 44.1-48.2] h) and reduced costs (narrow-spectrum: $4570 [$3751-5568] versus broad-spectrum: $5699 [$5005-$6491]). There were no differences in ED revisits or hospital readmissions. In summary, children's hospitals have low rates of narrow-spectrum antibiotic use for UTIs despite many reporting high rates of cefazolin-susceptible E. coli. These findings, coupled with the observed decreased LOS and costs among those receiving narrow-spectrum antibiotics, highlight potential antibiotic stewardship opportunities.