Duration of Antibiotic Therapy for Escherichia coli Bacteremia in Infants With Normal Cerebrospinal Fluid Studies and Without Meningitis.

OBJECTIVE

The optimal antibiotic duration for infants with Escherichia coli bacteremia with reliable, normal cerebrospinal fluid (CSF) studies and without meningitis is unknown. We evaluated whether treatment duration is associated with infection recurrence or mortality in these infants.

METHODS

This cohort study included infants discharged from Pediatrix Medical Group neonatal intensive care units between 2003-2022 with first instance of E coli bacteremia. Exclusion criteria included absence of CSF test results, CSF pleocytosis, positive culture or Gram stain from the CSF, delayed antimicrobial initiation (>2 days), or death/discharge during therapy. Antibiotic duration was categorized as <10, 10 to 14, or >14 days. Univariable analysis and multivariable logistic regression were used to assess associations between antibiotic duration and 30-day and in-hospital mortality, recurrence of infection, and the combined outcome of recurrence of infection or 30-day mortality. Sensitivity analysis excluded courses <5 days.

RESULTS

In 682 infants with E coli bacteremia, recurrence of infection or death following antibiotics occurred in 3% and was not associated with antibiotic duration (p = 0.82). After adjusting for gestational age and severe disease (defined as 1 or more of the following: mechanical ventilation, inotropic administration, or extracorporeal support) on the first day of bacteremia, antibiotic durations of 10 to 14 days were associated with lower odds of 30-day mortality (OR 0.18; 95% CI: 0.03-0.99) than antibiotic durations of <10 days. In the sensitivity analysis (N = 667), antibiotic duration was not predictive of any outcomes.

CONCLUSIONS

A 10-day course of antibiotics for E coli bacteremia with normal CSF results is likely sufficient for term and preterm infants.