Evaluation of Empiric Nafcillin Versus Vancomycin for Suspected Late Onset Sepsis in the Neonatal Intensive Care Unit

To compare clinical outcomes in neonates receiving empiric vancomycin or nafcillin containing regimens for neonatal late onset sepsis (nLOS).

This retrospective study evaluated neonates > 72 hours of age initiated on vancomycin/gentamicin (VANC) or nafcillin/gentamicin (NAF) for suspected nLOS. The primary composite endpoint was clinical worsening, defined as a composite of increased respiratory support or vasopressor requirement, both within the first 24 hours, or prolonged bacteremia. Secondary endpoints included acute kidney injury, methicillin-resistant Staphylococcus aureus colonization, deep-seated infection, and mortality.

The final cohort included 97 neonates (46 VANC, 51 NAF). There was no difference in the clinical worsening composite (VANC 15.2% vs NAF 15.7%; p = 0.95) or in the individual components of the composite. Secondary endpoints did not yield statistically significant differences.

Use of nafcillin as the Gram-positive empiric treatment agent did not result in increased clinical worsening compared to vancomycin at our institution.