Celiac Disease: Symptoms and Causes

Celiac disease is an autoimmune disease caused by your immune system’s reaction to gluten, the protein found in foods containing certain grains, primarily wheat, barley and rye. The gluten in these foods causes damage to the lining of the small intestine and limits its ability to get nutrients from the food you eat, leading to a serious condition called malabsorption.

Researchers have learned a lot about this autoimmune disorder, so Bottom Line Personal asked Columbia University gastroenterologist Suneeta Krishnareddy, MD, what you need to know about celiac disease now…

Celiac disease symptoms vary

Traditional thinking was that celiac’s calling cards were a combination of abdominal pain, weight loss and diarrhea. But now we know that’s not always the case. In fact, only about 30% of people who have celiac disease have these symptoms. The rest may experience the consequences of malabsorption, such as osteoporosis, iron deficiency or anemia, or joint pain. Some people report difficulty concentrating or brain fog. And then others don’t have any outward symptoms at all and learn they have celiac only as a result of a screening test.

What causes celiac disease?

Human leukocyte antigen (HLA) DQ2 and DQ8 are the two genes responsible for celiac disease. This genetic predisposition occurs in about 40% of the general population, yet only 1% develop celiac disease. That’s because it takes a combination of factors for celiac disease to occur.

It is not clear what the exact inflammatory celiac signature looks like, but a few studies have shown that early alterations in the gut microbiome from an infection may play a role. Example: People who had the norovirus or rotavirus infection as children are at slightly increased risk for celiac in adulthood.

Other factors: People with the celiac genes who were delivered by C-section seem to be at a slightly increased risk compared with those who were born vaginally, likely because their microbiomes are somewhat different. There’s also a link with breastfeeding—those who were not breastfed have a slightly higher risk for celiac. And there may be a correlation with the use of antibiotics in early childhood, but that has not yet been proven.

Diagnosing celiac disease 

Unlike many other autoimmune disorders, there are blood tests to diagnose celiac disease—specifically a test for the tissue transglutaminase IgA antibody (tTG-IgA) and the IgA antibody. If those antibodies are present, a test called an endoscopy will be done to look for damage to the lining of the small intestine and a biopsy, or tissue sample, will be taken at the same time in order to confirm the diagnosis.

If you suspected that you have celiac disease and started a gluten-free diet on your own but now want to be tested, getting a diagnosis is more complicated. The standard blood tests could give a false-negative. Reason: There needs to be gluten in your system to get a correct result. In this case, you would first be given a genetic test to look for the (HLA) DQ2 and DQ8 genes. If you test positive for these, you’ll go on a gluten challenge for three to six weeks, typically eating the equivalent of two slices of bread a day. Then the blood test and endoscopy/biopsy can be done to confirm whether or not you have the disease.

If you don’t have signs of celiac yourself but a first-degree relative has the condition, ask your doctor for screening tests (including tissue transglutaminase serology and genetic testing) to look for the (HLA) DQ2 and DQ8 genes. That is the definitive way to know if you’re at risk for celiac. Important: You’ll need follow-up screenings in the future if genetic testing is positive, because celiac disease can develop years later and at any age. Doctors do not recommend a gluten-free diet just because you’re at risk for celiac, but you should be screened regularly and be aware of the symptoms.

Treatment revolves around diet 

Celiac can’t be cured, but it can be successfully managed with a strict gluten-free diet to stop symptoms and help your intestines heal. This is a big, lifelong change, so it’s important to work with a gastroenterologist to confirm the condition, as well as a nutritionist who can help you craft a plan to avoid nutritional deficits that could lead to other health conditions.

Best: A “naturally” gluten-free diet based on fruits, vegetables, good sources of protein and whole grains that are gluten-free. Rather than eating a lot of white rice to replace pasta, try gluten-free quinoa, amaranth, millet, sorghum, teff, cornmeal (polenta) and 100% buckwheat, all rich in nutrients and fiber. Brown and wild rice are good, too.

Problem with gluten-free packaged baked goods: Many are loaded with unhealthy ingredients, such as rice flour and sugar, to simulate a “real” taste. Better: Look for baked goods made with the flours of the naturally gluten-free grains above—or bake them yourself.

What happens if you eat a gluten food occasionally? You need constant amounts of gluten to cause tissue damage, say 2 grams of gluten, or the equivalent of two slices of bread, every day for three weeks. So if you eat out and have a serving of pasta, which has an average of 5 grams of gluten, that one serving is not going to cause damage—but you are likely to experience gastrointestinal symptoms that feel even worse than they did before. That’s because gluten is a very inflammatory food, and once you start eating gluten-free, you become even more sensitive to it after just a few months.

Are there medications for celiac disease?

Clinical trials are underway for medications for patients with celiac, and immune-modulating therapies that improve the way you respond to gluten may be available as an adjunct, not a replacement for, a gluten-free diet in the future. But these medicines are not available commercially now.

Caution: Stay away from any so-called “gluten enzyme” products that claim to break down gluten similar to the way lactose pills work for people who are lactose-intolerant—there’s no equivalent for gluten. Also, there’s no reason to pay extra for non-food topicals, such as shampoo and body lotion, marketed as gluten-free since any gluten could not be absorbed through the skin. The one exception to this is lip balm and lipstick because you can ingest small amounts of gluten by licking your lips, eating, etc.

It is important to monitor your health and take precautions after a celiac diagnosis

Typically, you’ll have blood tests twice a year to check your levels of gluten antibodies and make sure they’re low enough to avoid damage to the intestines. A second endoscopy, often three to five years after you’ve started a gluten-free diet, is done to confirm that your intestinal tissue has healed.

Also recommended are yearly screens for other autoimmune diseases, the two most common being hypothyroidism and type 1 diabetes. These diseases run on the same gene as the Hla DQ 2 gene, and people with celiac are at increased risk for both. The development of hypothyroidism and type 1 diabetes isn’t related to gluten but rather to genetics, so even someone who has been gluten-free for 10 years could develop type 1 diabetes or hypothyroidism.

Everybody who has been diagnosed with celiac disease should have a bone density test to see if celiac has affected their bone mineralization and put them at risk for early osteoporosis. Your doctor may recommend another one a year or two after you’ve been on a gluten-free diet.

People with celiac disease who get pneumonia tend to get sicker than those without celiac, so the pneumonia vaccine is recommend, along with annual flu shots. Also: People with celiac don’t usually mount a response to hepatitis B in the same way the average person does. If you’ve been vaccinated for hepatitis B, get tested to see if the vaccine conveyed immunity. Some people with celiac have to do the whole hep B series two or three times before it actually takes effect.