Necrotizing enterocolitis

The survival of infants with necrotizing enterocolitis (NEC) has steadily improved since the late 20th century. The mortality rate in NEC ranges from 10% to more than 50% in infants who weigh less than 1500 grams (depending on the severity) compared with a mortality rate of 0-20% in babies who weigh more than 2500 grams. Extremely premature infants (1000 grams) are still particularly vulnerable, with reported mortality rates of 40-100%.^[1]

Of the infants who survive, about 50% develop a long-term complication and 10% of the infants will have late gastrointestinal problems, but the remaining 50% do not have any long-term sequelae.^[1][2] The 2 most common complications are intestinal stricture and short gut syndrome. Intestinal stricture occurs when an area of the intestine heals with scarring that impinges on the inside of the bowel. It is most common in infants treated without surgery. Short gut syndrome is the most serious post-operative complication in NEC, occurring in as many as 23% after resection. It is a malabsorption syndrome resulting from removing excessive or critical portions of the small bowel.^[1] The neonatal gut typically grows and adapts over time, but this growth may take up to 2 years, but it can result in persistent loose stools or frequent bowel movements.^[1][2]  Babies who can never successfully tube feed and/or who develop life-threatening liver disease may need organ transplantation.^[1]

Most of the babies who have not had extensive intestinal resection have normal gastrointestinal function at 1 to 10 years of age.^[2] 

Recurrent NEC is an uncommon complication (occurring in about 4-6%), but it can occur after either operative or nonoperative management of NEC. Infants who survive NEC are also at increased risk for neurodevelopmental problems; however, these problems may result from underlying prematurity rather than from NEC.^[1]

In a 2002 study of children who formerly had NEC (ranging from 5-10 years of age), the authors found that most children were enrolled in school full time, suggesting that children can expect a relatively favorable long-term outcome.^[3] A 1998 study looking at the long-term outlook for affected individuals reported that several years after having NEC, most long-term survivors achieved a normal quality of life with no persistent health problems.^[4]