Oral β-Lactam Antibiotics vs Fluoroquinolones or Trimethoprim-Sulfamethoxazole for Definitive Treatment of Enterobacterales Bacteremia From a Urine Source

In this cohort study of adults with E coli, Klebsiella spp, or Proteus spp bacteremia from a suspected urine source, the relative risk of recurrent bacteremia was not significantly higher with β-lactam antibiotics compared with fluoroquinolones or TMP-SMX, and the absolute risk and risk difference were small (ie, <3%). No significant difference in mortality was observed. Oral β-lactam antibiotics may be a reasonable step-down treatment option, primarily when alternative options are limited by resistance or adverse effects. Further study is needed because statistical power was limited owing to a low number of recurrent bacteremia events.