Celiac disease (nontropical sprue, gluten enteropathy, celiac sprue) is a hereditary intolerance to gluten (a protein found in wheat, barley, and oats) that causes characteristic changes in the lining of the small intestine, resulting in malabsorption.

• The intestinal lining becomes inflamed after a person ingests the protein gluten.
• Symptoms in adults include diarrhea, undernutrition, and weight loss, and symptoms in children include abdominal bloating and bulky, very foul-smelling stools.
• The diagnosis is based on typical symptoms and examination of a tissue specimen removed from the lining of the small intestine.
• Most people do well if they maintain a gluten-free diet.

Celiac disease is a hereditary disorder that usually affects people of northern European heritage. Celiac disease may affect 1 out of 300 people in Europe, especially in Ireland and Italy, and perhaps 1 out of 250 people in some parts of the United States, yet it is extremely rare in Africa, Japan, and China. About 10 to 20% of close relatives of people with celiac disease are also affected. The disease affects about twice as many women as men.

In this disease, gluten―a protein found in wheat and, to a lesser extent, barley, rye, and oats―stimulates the immune system to produce certain antibodies. These antibodies damage the inner lining of the small intestine, resulting in flattening of the villi. The resulting smooth surface leads to malabsorption of nutrients. However, the small intestine's normal brushlike surface and function are restored when the person stops eating foods containing gluten.

Symptoms

Some people develop symptoms as children. Others do not develop symptoms until adulthood. The severity of symptoms depends on how much of the small intestine is affected.

Most affected adults have weakness and loss of appetite. Diarrhea, often with oily or greasy-appearing stool, is common. Some people are undernourished, have mild weight loss, and occasionally have mouth sores and an inflamed tongue. However, some people do not have digestive symptoms at all. About 10% of people with celiac disease develop a painful, itchy skin rash with small blisters—a disease called dermatitis herpetiformis (see Blistering Diseases: Dermatitis Herpetiformis).

In children, symptoms can begin in infancy or early childhood after cereals (most of which contain gluten) are introduced. Some children experience only mild upset stomach, whereas others develop painful abdominal bloating and have light-colored, unusually foul-smelling, bulky stools (steatorrhea). Children typically fail to grow at a normal rate and appear weak, pale, and listless.

The nutritional deficiencies resulting from malabsorption in celiac disease can cause additional symptoms, which tend to be more prominent in children. Some children develop growth abnormalities, such as short stature. Anemia, causing fatigue and weakness, develops as a result of iron deficiency. Low protein levels in the blood can lead to fluid retention and tissue swelling (edema). Malabsorption of vitamin B₁₂ can lead to nerve damage, causing a pins-and-needles sensation in the arms and legs. Poor calcium absorption results in abnormal bone growth, a higher risk of broken bones, and painful bones and joints. Lack of calcium can also cause tooth discoloration and greater susceptibility to painful tooth decay. Girls with celiac disease may not have menstrual periods because of a low production of hormones, such as estrogen.

Diagnosis

Doctors suspect the diagnosis when a person has the previously mentioned symptoms. Measurement of the level of specific antibodies produced when a person with celiac disease consumes gluten is a helpful test. To help confirm the diagnosis, doctors remove a sample of tissue from the person's lining of the small intestine and examine it under a microscope (biopsy). The diagnosis is confirmed if the biopsy shows the intestinal villi are flattened and if the lining of the small intestine subsequently improves after the person stops eating foods containing gluten.

Once the diagnosis is made, doctors do blood tests to look for deficiencies of certain vitamins (such as folate [folic acid]) and minerals (such as iron and calcium).

Prognosis

Without diagnosis and treatment, celiac disease is ultimately fatal in 10 to 30% of people. Currently, such outcomes are rare, and most people do well if they avoid gluten.

Celiac disease does increase the risk of certain cancers of the digestive tract. The most common cancer is lymphoma of the intestine. Such lymphomas affect about 6 to 8% of people who have had celiac disease for a long time (typically more than 20 to 40 years). Strictly adhering to a gluten-free diet significantly decreases the risk of cancer.

Treatment

People with celiac disease must exclude all gluten from their diet, because eating even small amounts may cause symptoms. The response to a gluten-free diet is usually rapid. Once gluten is avoided, the brushlike surface of the small intestine and its absorptive function return to normal. Gluten is so widely used in food products that people with celiac disease need detailed lists of foods to be avoided and expert advice from a dietitian. Gluten is found, for example, in commercial soups, sauces, ice cream, and hot dogs.

Doctors give most people with celiac disease supplements to replace vitamins (such as folate) and minerals (such as iron).

Some people continue to have symptoms even when gluten is avoided. In such people, either the diagnosis is incorrect or the disease has progressed to a condition called refractory celiac disease. In refractory celiac disease, treatment with corticosteroids, such as prednisone, may help. In rare cases, if there is no response to either gluten withdrawal or drug treatment, intravenous feeding is needed. Sometimes children are seriously ill when first diagnosed and need a period of intravenous feeding before starting a gluten-free diet.

Last full review/revision January 2013 by Atenodoro R. Ruiz, Jr., MD