Necrotizing Enterocolitis

Abstract

Necrotizing enterocolitis (NEC) is the commonest inflammatory gastrointestinal disorder of newborn infants, occurring primarily in premature neonates. Presenting as a medical and surgical emergency, it is associated with significant morbidity and mortality. NEC is characterized by acute intestinal inflammation and necrosis with intramural dissection of gas, pathognomically appearing as pneumatosis intestinalis on radiography. The incidence and mortality, with an inverse relationship to maturation, range between 3-11% and 17-20% respectively. Mortality may be up to 50% in extremely premature infants who require surgery for intestinal perforation or gangrene. The exact etiopathogenesis is unknown. Over 90% of infants are premature and more than 98% are enterally fed. NEC presents with feeding intolerance and abdominal distension, which may rapidly progress to cardiorespiratory decompensation and death in severe cases. Intestinal dysbiosis and its functional and immunological immaturity are proposed to play roles in the pathogenesis. While exact triggers are undetermined, the disease is marked by an anomalous immunological response of enterocytes to inflammation, invoking cytokines and chemokines. NEC is treated with bowel rest, antibiotics, cardiorespiratory support, parenteral nutrition, and blood products transfusion. Approximately 30% of cases require surgery and a significant number of survivors suffer from neurological deficits, intestinal dysfunction, and post surgical short bowel syndrome.