Necrotizing enterocolitis of the neonate.

Necrotizing enterocolitis is the most common gastrointestinal emergency in the newborn. The syndrome strikes premature infants during the first 2 weeks of life. Abdominal distention, lethargy, and feeding intolerance are early signs of NEC that may progress to gastrointestinal bleeding and hemodynamic instability. The radiographic hallmark of NEC is pneumatosis intestinalis (air in the bowel wall). The ileum and colon are the usual sites of crepitant intestinal necrosis, leading frequently to perforation. In spite of appropriate medical therapy, about half of the infants with NEC develop intestinal gangrene or perforation and require surgery, consisting of bowel resection and enterostomy formation. The most common late complication, intestinal stricture, occurs in 15 to 35 per cent of recovered infants. Overall mortality from NEC ranges from 20 to 40 per cent. The etiology of NEC is poorly understood and is considered to be multifactorial, related to ischemia, bacterial colonization, and formula feedings in a susceptible infant. Future progress in the treatment of NEC may be achieved by earlier detection of necrosis, modification of gastrointestinal flora, or by bolstering the deficient gastrointestinal immune mechanisms of the premature neonate.