Definitions of neonatal Necrotizing Enterocolitis (NEC) in randomised controlled trials: a systematic review

Necrotizing Enterocolitis (NEC) is a significant cause of morbidity and mortality for preterm neonates. Although Bell's criteria are frequently used to assess stage of NEC, it was not a definition and, since its inception in 1978 and with the survival of neonates at earlier gestations, there is a requirement for an updated NEC definition. This systematic review aimed to evaluate the use of criteria for the diagnosis and staging of NEC in randomised clinical control trials.

This systematic review was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. A search was conducted through PubMed to identify Randomised Control Trials (RCTs) in the last twenty years that used NEC in the study title and in either the primary outcome or the inclusion criterion.

The initial search identified fifty-six RCTs. Thirty-six RCTs were included for full-text analysis. Thirty-three trials used Bell's criteria or Modified Bell's criteria to define NEC and three RCTs unique, author-created definitions.

There is consistent use of Bell's and Modified Bell's criteria of necrotizing enterocolitis in RCTs. However, international consensus on further modifications of the definition will greatly contribute to both research and clinical practice relating to NEC, in allowing greater consistency in the staging of NEC, and therefore optimal management.