Necrotizing enterocolitis: Susceptibility of premature infants

Immaturity of the intestinal epithelial barrier and the neonatal mucosal immune system predispose the premature infant to microbial invasion, which triggers the sequence of events leading to necrotizing enterocolitis (NEC). Stimulation of pro-inflammatory cytokines compromises intestinal defenses. An imbalance between epithelial cell injury and repair leads to a cycle of bacterial invasion, immune activation, uncontrolled inflammation, and gut barrier failure.