Q. How accurate are the blood tests for celiac disease?
A. The commonly used antibody tests (IgA anti-gliadin and anti-tissue trans glutaminase) can diagnose aobut 85-90% of those with celiac disease. A total IgA (immunoglobulin A) level must be done, because 10% of celiacs are deficient in this immunoglobulin, and these antibodies may be falsely low in this setting. On occasion, even those with biopsy-proven disease may test negative, so it is recommended that genetic testing for HLA-DQ2 and HLA-DQ8 genes be done. Either one or both are positive in 95-98% of celiacs, but are also present in about 25-30% of the population at large, so an intestinal biopsy remains the gold standard for diagnosis.
Health and happiness,
Dr. Jeffrey Aron
Gastroenterologist, San Francisco
(Dr. Aron is no longer taking questions.)
Mary says
I had been sick several years, bloating, not feeling well, IBS, leg pain, becoming very latharget, thyroid problem, ostheopinia. My gasterologist just said I didn’t eat enough fiber. Not true, I am very tuned into what my body does and how it reacts. I have learned a lot over the years. I had a friend and her boy has celiac and she suggested I go to his doctor. I went and she did the blood tests and it showed negative but didn’t do the biopsy and at that time I didn’t know enough to ask for it. She suggested I go gluten free, what would it hurt if I felt better, she said. I will tell you that it was a miracle. I have been gluten free for 6 years. If I eat gluten I am sick for 2 to 3 days afterwards. I definately react. My question is, since I didn’t have the biopsy, in your best quess, would you say we are accurate in saying I have celiac?