Necrotizing enterocolitis is injury to the inner surface of the intestine. This disorder occurs most often in very premature newborns.
Eighty-five percent of cases of necrotizing enterocolitis (NEC) occur in premature newborns. The cause is not understood. Diminished blood flow to the intestine in a sick premature newborn may result in injury to the inner layers of the intestine, allowing bacteria that normally exist within the intestine to invade the damaged intestinal wall and then enter the infant's bloodstream, causing infection (sepsis). If the injury progresses through the entire thickness of the intestinal wall and the intestinal wall tears (perforates), intestinal contents leak into the abdominal cavity and cause inflammation and usually infection of the abdominal cavity and its lining (peritonitis).
Symptoms and Diagnosis
Newborns with NEC may develop swelling of the abdomen. They may vomit bile-stained intestinal fluid, and blood may be visible in the stools. These newborns soon appear very sick and sluggish (lethargic) and have a low body temperature and repeated pauses of breathing (apnea). The diagnosis of NEC is confirmed by abdominal x-rays, which show gas has formed in the intestinal wall (pneumatosis intestinalis) or that free air is in the abdominal cavity if the intestinal wall has perforated. Blood samples are taken to look for bacteria and other indicators of sepsis.
Intensive medical treatment and surgery when needed have improved the outcome for newborns with NEC. About 60 to 80% of such newborns survive.
Prevention and Treatment
Feeding premature newborns their mother's breast milk rather than formula seems to provide some protection.
If NEC is present, feedings are stopped. A suction tube is passed into the stomach to remove pressure from swallowed air and milk, thereby decompressing the intestine. Fluids are given by vein to maintain hydration, and antibiotics are given immediately.
About 70% of newborns with NEC do not need surgery. However, surgery is needed if there is intestinal perforation with peritonitis. Surgery may also be needed if the condition progressively worsens despite treatment. The surgery involves removing the part of the intestine that has not been receiving its blood supply. The ends of the healthy intestine are brought out to the skin surface to create a temporary opening for the excretion of stools (ostomy). Later, when the infant is healthy, the ends of the intestine are reattached and the entire intestine is put back into the abdominal cavity.
In the tiniest and sickest newborns with peritonitis who may not survive more extensive surgery, peritoneal drains are placed into the abdominal cavity on each side of the lower abdomen. Peritoneal drains allow stools and peritoneal fluid to drain from the abdominal cavity and, along with antibiotics, may lessen symptoms. The procedure helps stabilize many newborns so that an operation can be done at a later time when the newborns are in less critical condition. In some cases, newborns recover completely without needing additional surgery.
Last full review/revision February 2009 by Arthur E. Kopelman, MD