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

Abstract

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 (≥ 37 weeks) with a diagnosis of NEC between 1990 and 2012. Patients were identified by ICD-9 and age. Early onset for NEC was ≤ 7 days and late onset after 7 days 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 b 0.05 was considered significant. Univariate outcomes with a p-value b 0.1 were selected for multivariable analysis. Results: Thirty-nine patients (24 boys, 15 girls) with median EGA of 39 weeks 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 7 days of life, have congenital heart disease, and/or need UA catheterization have increased mortality. © 2014 Elsevier Inc. All rights reserved. The pathogenesis of necrotizing enterocolitis (NEC) in infants remains incompletely understood. Most commonly, NEC occurs in the premature infant, with less than 10% occurring in full-term neonates It is not known whether the underlying pathophysiology of NEC in the term infant is distinctly different from that in the premature infant. In addition to the frequent presence of significant co-morbidities, term infants are frequently reported to present with NEC earlier in postnatal life Methods Patient Population We performed a two-center retrospective review of all full-term infants (≥ 37 weeks) with a diagnosis of NEC between 1990 and 2012. Charts were identified by including ICD-9 codes (777.5-777.6) and were reviewed to verify diagnosis of NEC and gestational age. Term infants determined to have Bell's stage 2 or 3 NEC were included. Term infants with possible Bell's stage I NEC were excluded from analysis. Infants who had an estimated gestational age less than 37 weeks were also excluded from the study. The subject met inclusion criteria for NEC if he/she had evidence of Bell's stage II or greater and had diagnosis of NEC documented in the chart with signs and symptoms that included temperature instability, apnea, bradycardia, lethargy, pneumatosis, metabolic acidosis, peritonitis, and/or pneumoperitoneum Similar to a previous publication, early-onset NEC was defined as development of NEC during the 1st week of life (≤ 7 days) and lateonset NEC as any time after day 7 of lif