Necrotizing enterocolitis

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at October 2, 2016
StartDiseasesNecrotizing enterocolitis

Premature infants suffer from many ailments due to improper bodily development. Necrotizing enterocolitis is a condition that is most likely to happen among premature children, and if it is not treated quickly, the disease may be very dangerous.

Contents

Definition & Facts

As the name implies, necrotizing enterocolitis happens when tissues in the body suffer from necrosis, and this tissue death causes many issues. Necrotizing enterocolitis specifically happens in the tissues of the intestines, and when it occurs it makes it impossible for patients to digest properly.

At first, only the lining of the intestinal wall is affected, but the necrosis can quickly spread through the rest of the gastrointestinal system. Each year, necrotizing enterocolitis is the second most prevalent cause of mortality among premature infants, and overall, black infants are three times as likely to have it as white infants.

Symptoms & Complaints

This medical condition does not happen in utero, but it can quickly develop once a baby is born. Typically, the time that the first symptoms of necrotizing enterocolitis start to occur is related to the age of an infant at birth.

Very premature babies tend to take longer to develop it, and babies who are born only slightly premature start showing symptoms very quickly. Since this condition most often happens among premature infants, premature babies are often monitored for signs and symptoms of necrotizing enterocolitis as soon as they are born.

At first, an infant may just lose their appetite, have slightly bloody stool, seem lethargic, have a temperature that fluctuates quickly, and retain fluid in their stomach after eating.

Over time, the infant will develop cysts filled with gas along their bowel wall, their stomach will look swollen and red, and they will cry whenever their stomach is touched.

As the tissue death progresses, symptoms quickly become more severe. Infants may go into shock, which is characterized by a very slowed breathing rate (bradypnea), and they can develop peritonitis which is a dangerous infection of the abdominal lining. 

Causes

The precise cause of necrotizing enterocolitis is unknown, but it clearly has something to do with the underdeveloped organs that many premature babies have. This medical condition only happens among infants who are either very ill or already premature, and it always starts with a small area of tissue dying. This tissue death most likely seems to be caused by a reduction in blood flow, but it can also be triggered by microbial infections.

If either the intestinal system or the circulatory system is underdeveloped, infants may not be able to get enough oxygen flowing to the intestines. Since a heavy growth of certain bacteria can also stimulate a case of necrotizing enterocolitis, it can also be caused by an outbreak of the condition in a nursery or day care. Though doctors are not positive of the exact spreading mechanism for necrotizing enterocolitis, it does seem to be somewhat contagious if several premature babies are in the same location.

Necrotizing enterocolitis is more common among formula-fed infants because human breast milk contains antibodies and immune system cells that can prevent infection.

Diagnosis & Tests

Since doctors will be on the lookout for necrotizing enterocolitis in premature infants, they normally start receiving tests for it as soon as they exhibit any signs or symptoms of the disease. Tests for necrotizing enterocolitis primarily rely on medical imaging tests to examine the state of an infant's bowels.

One of the most common tests is a computed tomography (CT) scan or X-ray of the bowels to look for the gas-filled cysts in the bowel wall which is also called pneumatosis intestinalis. This clinical sign is normally all that is needed for a necrotizing enterocolitis diagnosis in a premature infant.

Imaging tests of the abdominal region can sometimes show specific locations of necrosis if they are detailed enough. However, if the infant is not premature, doctors may not immediately start considering necrotizing enterocolitis, so more tests may be required to confirm the diagnosis.

A stool guaiac test can be used to determine whether or not stool contains blood because many infants have blood in their stool that is not visible. Other blood tests to look at electrolyte levels and arterial blood gas levels can be used to determine the severity of the condition.

Treatment & Therapy

The first step in treating necrotizing enterocolitis is typically to stop feeding the infant, especially if they are being fed through a feeding tube, so the bowels can rest and recover. During this time, the infant will be heavily monitored and receive intravenous fluids and electrolyte supplements.

Many infants suffer from excessive gas that can distend their stomach, so it may become necessary to insert a tube into the stomach to allow this gas to escape. In severe cases, infants can need help maintaining a steady heart rate.

If there is a large area of tissue death, a perforated bowel, or peritonitis, the infant may need surgery. Surgery will focus on removing any dead bowel tissue that is causing issues and then providing support to the gastrointestinal system.

During this surgery a portion of the intestinal tract may need to be removed, so some infants need a colostomy that puts a bowel opening through the abdominal wall and exiting the stomach. This allows infants to get nutrition and pass waste without using the portion of the intestines that is damaged due to the necrotizing enterocolitis. The colostomy is often reversed and closed up at a later date once the infant is healthier. 

Prevention & Prophylaxis

Premature infants need heavy monitoring and carefully formulated feedings to ensure that they do not develop necrotizing enterocolitis. Feeding infants with human breast milk is the best method of preventing.

If formula must be used, a higher amount of fats in the formulas can help to reduce the chances of developing necrotizing enterocolitis. Probiotic supplementation is also beneficial because it seems to prevent the necrotizing enterocolitis from becoming severe if it does develop.