Comparison of intravenous and oral definitive antibiotic regimens in hospitalised patients with Gram-negative bacteraemia from a urinary tract infection

Transitioning patients from intravenous (IV) to oral antibiotic therapy has been shown to be a successful approach for several infections. However, minimal data exist evaluating outcomes following transition from to oral antibiotics for patients with bacteraemia secondary to a urinary tract infection (UTI). This study compared treatment failures between patients treated exclusively with IV antibiotics and those transitioned from IV to oral antibiotics for bacteraemia secondary to UTI.This single-centre, retrospective cohort study included hospitalised, non-critically ill adult patients treated with culture-susceptible antibiotic therapy for 7-21 days. Patients were divided into two cohorts based on the route of definitive antibiotic administration. Treatment failure was a composite outcome of death and recurrence of the index micro-organism within 21 days following negative blood cultures.Among the 346 patients enrolled, 82 (23.7%) were in the IV cohort and 264 (76.3%) were in the IV-to-oral cohort. A total of six treatment failures occurred; 2 (2.4%) in the IV cohort and 4 (1.5%) in the oral transition cohort (hazard ratio=0.62, 95% confidence interval 0.11-3.39; P=0.58). All failures were due to recurrence of the index organism. Secondary outcomes demonstrated a significantly higher rate of IV line-associated complications in the IV cohort (P=0.03) and a favourable hospital length of stay in the oral cohort (P<0.001). Patients transitioned from IV to oral antibiotics based on culture-susceptibility data experienced similarly low rates of treatment failure as those who received exclusive IV therapy.