Frequently Asked Questions
Why is celiac so difficult to diagnose?
There are several reasons why celiac can be very difficult to diagnose. Often, it presents with seemingly unrelated symptoms – from fatigue and joint pain to anemia and infertility. It can also be confused with other conditions, such as irritable bowel syndrome, Crohn's disease, ulcerative colitis, bacterial overgrowth syndrome, intestinal infections, chronic fatigue syndrome and depression. Compounding the problem is the fact that many physicians simply were not educated on diagnosing celiac disease.
Is celiac usually diagnosed in children or adults?
You can be diagnosed with celiac disease at any age. In many cases, adults who are diagnosed have had the disease for years and not received a proper diagnosis. The Jefferson Celiac Center specializes in diagnosing and treating children and adults.
Can blood tests be used to diagnose celiac disease?
Yes, blood tests can be useful in diagnosing celiac disease. People with celiac have elevated levels of certain antibodies – that is, proteins that target the body's own cells or tissues. Blood tests can help determine if such antibodies are present. Antibodies include tissue transglutaminase, endomysial and giladin.
Another blood test that should be checked along with antibody testing is for IgA deficiency – something that occurs more commonly with celiac disease and can affect the reliability of the antibody testing.
Can blood tests alone confirm a diagnosis of celiac disease?
In a word, no. If the blood tests and symptoms suggest celiac disease, the next step is typically an upper endoscopy with small bowel biopsy – the best way to confirm a diagnosis of celiac. Through this procedure, tiny pieces of tissue are removed from the small intestine to check for damage to the villi (the tiny, finger-like protrusions of the small intestine). During this procedure, you are sedated, and the physician inserts a long, thin tube (endoscope) through the mouth and stomach into the small intestine. The physician takes a sample of tissue using instruments passed through the endoscope.
A biopsy is the best way to confirm the presence of celiac disease and to rule out other conditions that can mimic celiac disease.
What is the connection between the skin condition called dermatitis herpetiformis (DH) and celiac disease?
Dermatitis herpetiformis (DH) – an itchy, blistering skin condition – occurs in association with celiac disease.
The painful rash of DH may appear anywhere, but usually on the knees, elbows and/or buttocks. Interestingly, many individuals with DH do not have digestive symptoms of celiac disease. What's more, nearly half of those with DH do not test positive when their blood samples are analyzed. Even so, they almost always have the same intestinal damage as people with celiac disease.
DH is confirmed through a skin biopsy – the removal and testing of a small piece of skin near the rash. The presence of the IgA antibody confirms a diagnosis of DH and, by extension, celiac disease. Thus, if you have DH, you almost certainly have celiac disease. Though you would need to begin following a gluten-free diet, we would advise seeing our celiac disease specialists first, as additional baseline testing may be helpful for future management.
Who should be tested for celiac disease?
Among adults, the following individuals should be tested for celiac disease:
- Any person with dermatitis herpetiformis (DH)
- Any person with a first-degree relative with celiac disease (5 to 10 percent risk of celiac disease)
- Any person who has a related autoimmune disorder, even if there are no symptoms of celiac. Those disorders include insulin-dependent diabetes mellitus, Hashimoto's thyroiditis, Turner syndrome, Williams syndrome, Graves' disease and Sjögren's syndrome.
- Any person with Down syndrome.
- Any woman who has experienced recurrent miscarriages or infertility where no other medical cause has been identified.
- Any individual who has experienced persistent gastrointestinal symptoms, dental enamel hypoplasia, fatigue, bone density problems and other signs and symptoms.
Once you have been tested, is there ever a reason to be retested?
There are three factors that combine to cause celiac disease:
- An over-responsive immune system
- A genetic predisposition to the disease
- Elements of your environment
We know for certain that people are born with the genes that make them vulnerable to developing celiac disease. We also know that gluten – a protein found in wheat, barley and rye – is what triggers the autoimmune response. However, the environmental factors present some unknowns. Some individuals can consume foods with gluten for years or even decades before developing the disease. In other people, celiac disease can be "silent," so while a person is eating foods with gluten and appears to be fine, he or she is not, in fact, healthy. Finally, most individuals with the genetic predisposition for getting celiac disease – even if someone in their family has celiac disease – will never develop the disease regardless of their diet.
The bottom line: Celiac can develop at any time in people with the genes for celiac disease, in people with a related autoimmune disorder (namely, insulin-dependent diabetes mellitus, Hashimoto's thyroiditis, Turner syndrome, Williams syndrome, Graves' disease and Sjögren's syndrome), and in people with Down syndrome. Thus, it is important for such individuals to be tested regularly. An early diagnosis can help prevent the development of other autoimmune diseases, as well as a variety of other complications of celiac.
Is there a way to screen for celiac?
Most screening is done with antibody testing, but occasionally genetic testing is helpful. Genetic testing can help determine whether or not an at-risk person carries the genes responsible for celiac disease. It turns out that one-third of the U.S. population has at least one of these two genes. Therefore, having the gene does not mean you have celiac disease, but it does mean you have the possibility of developing it at some point in your life.
First-degree relatives – parents, children and siblings – of someone with celiac disease have a 5 to 10 percent chance of developing the disease themselves and should be screened. If the genetic screening shows the presence of the genes that make someone vulnerable to get celiac, regular antibody testing should be performed to determine if and when the disease becomes active. Between testing, it is important to see your physician if symptoms suggestive of celiac disease develop.
Though some countries offer screening at birth, such as Italy, currently there is no "simple" way to screen for celiac disease in the U.S. population at large.
If celiac disease is suspected, should a person do a "trial" of a gluten-free diet?
It is not advisable to initiate a gluten-free diet without a medical evaluation. After a few months on this diet, the opportunity to establish a definite diagnosis may be lost because both antibody tests and the small intestine biopsy become normal. Knowing whether or not you truly have celiac disease has lifelong implications for your care and that of your first-degree relatives. Thus, waiting a few weeks and seeing your physician before going on a gluten-free diet is strongly recommended.