Necrotizing enterocolitis in infants with periventricular hemorrhagic infarction: Associations and outcomes

Background: Necrotizing enterocolitis (NEC) and periventricular hemorrhagic infarction (PVHI) are complications of prematurity associated with poor neurodevelopmental outcomes. Objectives: We characterized temporal and causal associations between NEC and type of PVHI as well as associations with outcomes. Methods: This was a multicenter retrospective study of infants with birth weight <1,500 g and diagnosis of PVHI by a pediatric radiologist at 3 neonatal intensive care units in North Carolina, USA, between January 1998 and December 2004. NEC was confirmed using radiological and surgical pathology findings. Infants were assessed by 3 years using the Bayley Scales of Infant Development, second edition. Results: 35 of 112 (31%) of study patients developed NEC. NEC was diagnosed subsequent to PVHI by a median of 16.6 days (95% CI [9.5, 24.9], p < 0.0001). Indomethacin use and the presence of bilateral PVHI were associated with an increased risk of subsequent NEC (OR 2.8, 95% CI [1.1, 7.2] and OR 2.4, 95% CI [1.1, 5.7], respectively). Having bilateral versus unilateral PVHI was associated with a 2.34-fold increased risk of death (95% CI [1.27, 4.33], p = 0.007). NEC was not associated with worse motor outcomes in this population. Overall, the probability of a mental development index >70 was greatest for infants with unilateral PVHI versus bilateral PVHI, although the presence of NEC was associated with worse cognitive outcomes in both groups. Conclusions: Premature infants with PVHI often subsequently develop NEC, especially if they have bilateral PVHI and are exposed to indomethacin. While NEC results in worse neurodevelopmental outcomes, PVHI severity appears more important to the outcome of these infants.