NECROTIZING ENTEROCOLITIS

Background 1. Pathogenesis is multifactorial. a. Immaturity of the GI tract is the most important factor. i. Immaturity results in intestinal hyperpermeability. ii. Decreased peristalsis increases the time intestinal bacteria are in contact with carbohydrate substrates from feedings and increases the time the bowel is exposed to bacterial antigens, thus increasing inflammation. iii. Decreased immunoglobulin A (IgA) production by the immature intestine compromises an important protective mechanism against pathogens. b. It is thought that an exaggerated inflammatory response occurs after the exposure of bacterial pathogens colonizing the gut to substrate provided by enteral feedings. c. A perinatal hypoxic-ischemic episode preceding NEC may be the inciting event in some cases; however, this is unlikely to be the overall primary cause because the age of onset for NEC, about 21 days in preterm neonates, is remote from birth, and no such event is identifiable in many cases of NEC. d. Necrosis usually involves the ileum and proximal colon.

#Enterocolitis #pediatrics #neonates