Late onset of necrotizing enterocolitis in the full-term infant is associated with increased mortality: results from a two-center analysis.

PURPOSE: The effect of timing of onset of necrotizing enterocolitis (NEC) on outcomes has not been determined for the full-term infant. In this study we aimed to characterize the full-term NEC population and to evaluate onset of NEC.

METHODS: We performed a two-center retrospective review of all full-term infants (≥ 37weeks) with a diagnosis of NEC between 1990 and 2012. Patients were identified by ICD-9 and age. Early onset for NEC was ≤7days and late onset after 7days of life. Demographics, comorbidities, maternal factors, clinical factors, surgical intervention, complications, and mortality were evaluated. Wilcoxon's test was performed on continuous variables and Fisher's exact test on categorical data. A p-value<0.05 was considered significant. Univariate outcomes with a p-value<0.1 were selected for multivariable analysis.

RESULTS: Thirty-nine patients (24 boys, 15 girls) with median EGA of 39weeks were identified. Overall mortality was 18%. Univariate predictors of mortality included congenital heart disease and placement of an umbilical artery (UA) catheter. Multivariate analysis revealed late onset of NEC to be an independent predictor of mortality (OR 90.8, 95% CI 2.6-3121).

CONCLUSION: Full-term infants who develop NEC after 7days of life, have congenital heart disease, and/or need UA catheterization have increased mortality.