What is celiac disease?
Celiac disease is a disease in which there is a hereditary allergy to gluten that injures the lining of the small intestine. It is also called celiac sprue. Gluten is a protein found in wheat, rye, and barley. The small intestine is the long food tube that digests and absorbs nutrients from the food you eat into your body. Gluten intolerance refers to both celiac disease and other conditions in which gluten causes symptoms or illness.
The immune system defends the body against germs (bacteria and viruses) and other foreign substances. In celiac disease, the immune system does not function properly and attacks part of the patient's own body, the small intestine, when exposed to gluten. This is an example of an autoimmune disease. The lining of the small intestine consists of millions of small, fingerlike structures called villi that enable the small intestine to efficiently absorb nutrients into the body. These villi are damaged in celiac disease.
What are the symptoms of celiac disease?
By damaging the small intestine and impairing the absorption of nutrients, celiac disease can cause digestive symptoms and nutritional deficiencies. It can cause:
--Diarrhea --Gas (flatulence)
--Abdominal bloating --Abdominal pain (stomach pain)
--Change in mood --Slowed growth in children
--Osteoporosis (weak, brittle bones) --Abnormal liver enzymes
--An itchy skin rash called dermatitis herpetiformis
--Vitamin and mineral deficiencies (iron, calcium, vitamin B12, folate, vitamin D, copper, zinc)
These symptoms may also be caused by many diseases other than celiac disease. Most people with celiac disease have at least one of these symptoms, but occasionally celiac disease may not cause any symptoms. Celiac disease is a lifelong disease. It may occur in children or adults. It is found in 10% of close relatives of celiac disease patients.
How is celiac disease diagnosed?
Celiac disease can be missed for a long time because some of the symptoms are like those of other diseases. Many patients with celiac disease have been diagnosed with other conditions such as irritable bowel syndrome or iron deficiency anemia for years. Once your doctor suspects celiac disease, you should get a blood test. Dr. Albert M. Harary, in his New York City office, will order a blood test called a transglutaminase antibody or an endomysial antibody. This test is positive in 97-100% of patients with celiac disease. It occasionally is positive in people who do not have celiac disease. Some doctors will order the gliadin antibody blood test, but this test is not very helpful, as it is frequently positive in people without celiac disease.
There is a second important test that Dr. Albert M. Harary uses to diagnose celiac disease: upper GI endoscopy (EGD). Please refer to the Services section in this website on this procedure. In this test, the patient is sedated and a thin tube with a camera is passed painlessly through the mouth down into the intestine to obtain biopsies of the small intestine. Biopsies are small fragments of tissue which are pinched off the lining of the small intestine. The biopsies are then examined under a microscope. In celiac disease, the biopsies will show shrinkage or loss ("atrophy") of the villi and inflammation in the lining of the small intestine. Rarely, Dr. Harary uses wireless capsule endoscopy to diagnose celiac disease when the diagnosis is uncertain after a conventional upper GI endoscopy (EGD) and small intestinal biopsy.
People should not go on a gluten-free diet until after these tests are done, because the tests may miss celiac disease if they are done while the patient is already on a gluten-free diet. When Dr. Harary sees a patient with suspected celiac disease who was already on a gluten-free diet but has not been adequately tested yet, he uses one of the 3 following approaches:
- Genetic tests for HLA DQ2 and HLA DQ8. If these tests are negative, it is very unlikely that celiac disease is present. However a positive test is found at 30% of people without celiac disease, so a positive test is not useful.
- Going back on a diet that contains moderate amounts of gluten for 3-4 weeks before having the blood test and an upper GI endoscopy (EGD).
- Testing with blood tests and/or endoscopy while staying on a gluten-free or low gluten diet. This is a less accurate approach, but can be useful if the tests still show evidence of celiac disease.
Dr. Harary will discuss these options during your visit to his New York City office.
Some people whose symptoms improve on a gluten-free diet do not have celiac disease, but had non-celiac gluten sensitivity (or intolerance). The blood test and small intestinal biopsy will be normal in patients with non-celiac gluten sensitivity. It is helpful to know whether you have celiac disease or non-celiac gluten sensitivity (or intolerance). This is because celiac disease patients often require a stricter gluten-free diet and require monitoring for nutritional deficiencies and other consequences of their celiac disease.
How is celiac disease treated?
A gluten-free diet is the only treatment for celiac disease. Completely avoiding gluten will allow the small intestine to heal. Eating even small amounts of gluten will continue to harm the small intestine. You should not go on a gluten-free diet until your doctor has done specific tests for celiac disease.
A gluten-free diet is difficult to maintain. A registered dietitian with experience with celiac disease should be consulted to assist. Wheat, barley, rye, and triticale are the grains that contain gluten. Spelt and kamnut are forms of wheat. You should check the ingredient labels of all processed foods that you eat. Flour, semolina, farina, pasta, matzah, croutons, and breading contain wheat. In addition, many foods often have added wheat products. These include:
Brown rice syrup Chips/potato chips Candy
Communion wafers French fries Gravy
Imitation fish or bacon Rice mixes Sauces
Seasoned tortilla chips Self-basting turkey Soy sauce
Soups and bouillion cubes Vegetables in sauce Marinades
Commercial cereals Stuffings Modified food starch
Malt vinegar Dextrin Textured vegetable protein (TVP)
Hydrolyzed plant protein (HPP) Vegetable gum Hydrolyzed vegetable protein(HVP)
Cold cuts, hot dogs, salami, sausage
Many medications, both prescription and over-the-counter, as well as nutritional and vitamin supplements, lipstick, and lip balm also contain gluten as a filler. Restaurants and travel often lead to exposure to gluten, and careful attention is needed.
Foods that are okay include:
Amaranth Arrowroot Buckwheat
Cassava Corn Flax
Nuts Vegetables Potatoes
Quinoa Rice Seeds
Soy (but not many soy sauces) Sorghum Tapioca
Yucca Millet Nut flours
Research is being conducted on special enzymes to digest gluten before it can do damage, and other medications, but none of these is ready for general use. A careful, gluten-free diet remains the only effective treatment and must be continued permanently.
To learn more about celiac disease diagnosis and treatment offered by Dr. Harary, please contact our New York City office.