Celiac disease is a gluten-related autoimmune disease with bowel-related symptoms early in the disease. It is the most common of all autoimmune diseases. Chronic celiac disease may produce widespread symptoms in the body due to poor absorption of nutrients by the intestine. Chronic celiac disease can be confused with other disease processes as a result of malabsorption. It occurs in 1-2% of the population.
Gluten occurs mainly in wheat, barley and rye, and Americans eat about 15-25 grams of gluten per day. A single slice of bread contains 3 grams of gluten, which can cause abdominal pain and bloating.
Since gluten resists digestive enzymes, large immune-stimulating proteins are sent to the small intestine. These proteins cause inflammation and destruction to the lining of that intestine. This inflammation eventually causes destruction of the microscopic anatomy, resulting in malabsorption of essential nutrients. Inflammation causes the formation of antibodies which can enter the blood stream and perpetuate the problem with continued consumption of gluten.
Untreated celiac disease can cause osteoporosis, osteopenia, fractures, iron deficiency anemia, miscarriages, amenorrhea, and adenocarcinoma of the intestine. It also increases mortality by 30-40%. It must be excluded in cases of unexplained gastrointestinal symptoms, unexplained iron deficiency, men with osteoporosis, and women with early osteoporosis.
The symptoms of celiac disease include gastroesophageal reflux, dizziness, headaches, chronic fatigue, numbness and tingling of hands or feet, diarrhea, constipation, bloating, and unexplained anemia. Celiac disease can be misdiagnosed as stress, osteoporosis, multiple sclerosis, Lyme disease, temporal arteritis, and pernicious anemia.
Definitive diagnosis of celiac disease is made first by blood testing for immunoglobulins, followed by small bowel biopsy. Probably 3 million people in the U.S. have celiac disease, but only about 10% are diagnosed. Finland is the country with the highest rates of diagnosis at 70% of people likely to have the disease. It is a small country with good screening programs, and Finnish restaurants and grocery stores have many gluten-free options available.
Treatment by dietary exclusion of gluten is only partly successful, and the damaged intestine is unlikely to return to normal even with proper diet. Treatment is only partly successful because of contamination of all grains with gluten in the field, factory and kitchen. Thirty-two percent of gluten-free grains, seeds and flours have over 30 parts per million of gluten from cross contamination. Two-thirds of patients are still symptomatic after 8-12 years of treatment, and inflammation of the intestine persists. The area of the intestine for absorption should be the size of a tennis court, but is only about the size of a kitchen table even after long term treatment.
In addition to gluten-free diets, pharmaceutical treatments are being researched for use in addition to gluten-free diets. Dr. Adelman of UCSF is associated with a lab studying a drug to degrade the immunogenic ability of gluten. The drug decreases the size of the immunogenic proteins that get to the bowel, and is successful in reducing the injury to the intestinal lining caused by gluten.
Unlike celiac disease, “gluten sensitivity” is not an allergy and is not autoimmune. Gluten sensitivity causes symptoms related to gluten which may improve on a reduced-gluten diet. This occurs in 5-20% of the population. The symptoms are caused by eating gluten, and the diagnosis of celiac disease must be excluded. True “wheat allergy” occurs in 1% of the population and is an allergy to wheat protein.
Adelman, DC, Celiac Disease and Gluten-Related Autoimmunity. UCSF Medical Grand Rounds. University of California at San Francisco, San Francisco, California, USA.