# Safety and efficacy of early oral switch in Enterobacterales bacteremia: a systematic review and meta-analysis

## TL;DR

Switching to oral antibiotics early in treating Enterobacterales bacteremia may reduce treatment failure, especially if done within 4 days.

## Contribution

This study provides the first systematic review and meta-analysis on the safety and efficacy of early oral switch in Enterobacterales bacteremia.

## Key findings

- Early oral switch reduces treatment failure compared to continued IV therapy (RR 0.72).
- Switching within 4 days showed the greatest benefit (RR 0.58).
- Switching after 4 days showed no significant advantage (RR 0.87).

## Abstract

Early oral switch (EOS) has been proposed as an alternative to prolonged intravenous (IV) therapy for Enterobacterales bacteremia; however, its safety and effectiveness have not been clearly established. This systematic review and meta-analysis evaluated whether EOS reduces treatment failure in uncomplicated Enterobacterales bacteremia and examined how the timing of switching affects outcomes.

We conducted a systematic review and random-effects meta-analysis of randomized controlled trials and observational studies that compared EOS with continued IV therapy in adults with uncomplicated Enterobacterales bacteremia. Pooled risk ratios (RRs) with 95% confidence intervals (CIs) were calculated using random-effects models. The primary outcome was treatment failure by ≤90 days. Prespecified analyses evaluated the timing of the switch.

Across 10 studies that met the inclusion criteria, EOS was associated with lower treatment failure than continued IV therapy (RR, 0.72; 95% CI, 0.58–0.89; I²=26%). Switching within 4 days reduced the failure (RR, 0.58; 95% CI, 0.44–0.76; I²=0%), whereas switching after 4 days showed no clear advantage (RR, 0.87; 95% CI, 0.71–1.06; I²=0%). No evidence of small study effects was observed.

EOS was associated with a lower risk of treatment failure than prolonged IV therapy, with the greatest benefit observed when the switch occurred within 4 days. These findings should be interpreted with clinical caution given that most of the evidence is observational.