The abdomen may be swollen, stools may be bloody, and the newborn may vomit a greenish, yellow, or rust-colored fluid and appear very sick and sluggish.
The diagnosis is confirmed by abdominal x-rays.
About 70 to 80% of newborns with this disorder survive.
Treatment involves stopping feedings, passing a suction tube into the stomach to remove stomach contents to relieve pressure, and giving antibiotics and fluids by vein (intravenously).
In severe cases, surgery is required to remove the damaged intestine.
Over 90% of cases of necrotizing enterocolitis occur in premature newborns Premature Newborn A premature newborn is a baby delivered before 37 weeks of gestation. Depending on when they are born, premature newborns have underdeveloped organs, which may not be ready to function outside... read more . Necrotizing enterocolitis may occur in clusters or as outbreaks in neonatal intensive care units (NICUs). Sometimes these outbreaks can be linked to specific bacteria (such as E. coli Escherichia coli Infections Escherichia coli (E. coli) are a group of gram-negative bacteria that normally reside in the intestine of healthy people, but some strains can cause infection in the digestive... read more ), but often the cause is not known.
The cause of necrotizing enterocolitis is not completely understood, but it is in part related to immaturity of the intestine along with low oxygen levels in the blood and/or diminished blood flow to the intestine. Diminished blood flow to the intestine in a sick premature newborn may result in injury to the inner surface of the intestine. The injury allows bacteria that normally exist within the intestine to invade the damaged intestinal wall and then enter the newborn’s bloodstream, causing infection (sepsis Sepsis in Newborns Sepsis is a serious bodywide reaction to infection spread through the blood. Newborns with sepsis appear generally ill—they are listless, do not feed well, often have a gray color, and may have... read more ) and sometimes death. If the injury progresses through the entire thickness of the intestinal wall and the intestinal wall tears (perforates) Perforation of the Digestive Tract Any of the hollow digestive organs may become perforated (punctured), which causes a release of gastrointestinal contents and can lead to sepsis (a life-threatening infection of the bloodstream)... read more , intestinal contents leak into the abdominal cavity and cause inflammation and usually infection of the abdominal cavity and its lining (peritonitis Peritonitis Abdominal pain is common and often minor. Severe abdominal pain that comes on quickly, however, almost always indicates a significant problem. The pain may be the only sign of the need for surgery... read more ).
In addition to prematurity Premature Newborn A premature newborn is a baby delivered before 37 weeks of gestation. Depending on when they are born, premature newborns have underdeveloped organs, which may not be ready to function outside... read more , other risk factors include
Prelabor rupture of the membranes Prelabor Rupture of the Membranes (PROM) Prelabor rupture of the membranes is the leaking of amniotic fluid from around the fetus at any time before labor starts. After the membranes rupture, labor often soon follows. If labor does... read more (the mother's water breaks more than 12 hours before labor begins): The leaking amniotic fluid can lead to an infection in the fetus.
Disturbance of the bacteria that live in the digestive system: Treatment with antibiotics or acid-suppressing drugs can encourage growth of potentially harmful bacteria that may penetrate the intestine.
Perinatal asphyxia Perinatal asphyxia Birth injury is damage that occurs as a result of physical pressure during the birthing process, usually during transit through the birth canal. Many newborns have minor injuries during birth... read more : This disorder involves a decrease in blood flow to the newborn's tissues or a decrease in oxygen in the newborn's blood before, during, or just after delivery.
Heart disease present at birth Overview of Heart Defects About one in 100 babies is born with a heart defect. Some are severe, but many are not. Defects may involve abnormal formation of the heart's walls or valves or of the blood vessels that enter... read more (congenital heart disease): Birth defects of the heart may affect the way blood flows or affect the levels of oxygen in the blood.
Anemia Anemia in the Newborn Anemia is a disorder in which there are too few red blood cells in the blood. Anemia can occur when red blood cells are broken down too rapidly, too much blood is lost, or the bone marrow does... read more (low number of red blood cells): In anemia, it can be difficult for a newborn's blood to carry an adequate supply of oxygen.
Exchange transfusions Exchange transfusion Jaundice is a yellow color to the skin and/or eyes caused by an increase in bilirubin in the bloodstream. Bilirubin is a yellow substance formed when hemoglobin (the part of red blood cells... read more : During this procedure, the newborn's blood is removed and replaced, which may affect blood flow to the organs.
Formula feeding: Breast milk contains substances that help protect the walls of the digestive tract that formulas do not have.
Symptoms of NEC
Newborns with necrotizing enterocolitis may develop swelling of the abdomen and may have difficulty feeding. They may vomit bloody or green- or yellow-stained 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).
Diagnosis of NEC
X-rays of the abdomen
The diagnosis of necrotizing enterocolitis is confirmed by abdominal x-rays Plain X-Rays X-rays are high-energy radiation waves that can penetrate most substances (to varying degrees). In very low doses, x-rays are used to produce images that help doctors diagnose disease. In high... read more that show gas in the intestinal wall (called pneumatosis intestinalis) or that free air is in the abdominal cavity if the intestinal wall has perforated. Doctors may also do an ultrasound of the abdomen to look at the thickness of the intestinal wall, pneumatosis intestinalis, and blood flow.
Blood samples are taken to look for bacteria and other abnormalities (for example, a high white blood cell count).
Prognosis for NEC
Current medical and surgical treatments have improved the prognosis for infants with necrotizing enterocolitis. About 70 to 80% of affected newborns survive.
Narrowing of the intestine (intestinal stricture) is the most common long-term complication. Strictures occur in 10 to 36% of infants who survive the initial episode of necrotizing enterocolitis. Strictures typically cause symptoms 2 to 3 months after the episode of necrotizing enterocolitis. Sometimes strictures need to be corrected surgically.
Prevention of NEC
Feeding premature newborns their mother’s breast milk Breastfeeding Breast milk is the ideal food for newborns. Although babies may be fed breast milk or formula, the World Health Organization (WHO) and American Academy of Pediatrics (AAP) recommend exclusive... read more rather than formula seems to provide some protection against necrotizing enterocolitis. In addition, hospital personnel avoid giving the infant highly concentrated formula and take measures to prevent low oxygen levels in the infant's bloodstream. Antibiotics and acid-supressing drugs also should be avoided when possible.
There is some evidence that probiotics (good bacteria) may be helpful in prevention, but this therapy is still experimental.
Pregnant women who are at risk of having a preterm birth may be given corticosteroids to help prevent necrotizing enterocolitis.
Treatment of NEC
Nutrition, fluids, and antibiotics given by vein
Newborns who have necrotizing enterocolitis remain in the hospital and are treated in the neonatal intensive care unit (NICU) Neonatal intensive care unit (NICU) Problems in newborns may develop Before birth while the fetus is growing During labor and delivery After birth About 10% of newborns need special care after birth due to prematurity, problems... read more .
Feedings are stopped in newborns with necrotizing enterocolitis. A suction tube is passed into the newborn's stomach to remove its contents, which decreases pressure and helps prevent vomiting. Nutrition and fluids are given by vein to maintain hydration and nutrition and allow the intestine to heal. Antibiotics are given by vein to treat infection.
Over 75% of newborns with necrotizing enterocolitis do not need surgery. However, surgery is needed if there is intestinal perforation or part of the intestine is severely affected. The surgery involves removing the part of the intestine that has not been receiving enough blood. The ends of the healthy intestine are brought out to the skin surface to create a temporary opening to allow the intestines to drain (ostomy). Later, when the infant is healthy, the ends of the intestine are reattached and the intestine is put back into the abdominal cavity.
In extremely small (about 1 pound or less, or less than 600 grams) or seriously ill infants who may not survive more extensive surgery, doctors may place peritoneal drains into the abdominal cavity. Peritoneal drains allow the infected material in the abdomen to drain out of the body and may lessen symptoms. The procedure helps stabilize these infants so that an operation can be done at a later time when they are in less critical condition. In some cases, infants recover without needing additional surgery.