This panel contains the following tests:

• Deamidated gliadin IgA — This test may be positive in some people with CD who are negative for tTG, especially children less than 2 years old.
• Tissue transglutaminase IgA — This is the most sensitive (>90%) and specific (>95%)^1-3 blood test for celiac disease and is preferred for the detection of CD in people over 2 years of age.  Although "tissue" is in the name of this test it is measured in the blood.
• Serum IgA level — This test is used to detect IgA deficiency. This deficiency occurs in about 2-3% of people with CD leading to false negative test results.

Celiac disease is a lifelong digestive disorder affecting both children and adults. The disease is likely under-diagnosed in that it may affect as much as 1% of the population of the United States. This condition is characterized by an immune-mediated reaction to gluten that causes inflammation in the small intestine and does not allow food to be properly absorbed.

Celiac disease is not a food allergy and is not the same as a wheat allergy… it is actually an autoimmune disease. This screening test is for anyone who suspects that grains like wheat, spelt, rye, and barley may be affecting their health. It is also suggested that a food safe allergy test be done as well since a person can react to wheat/grains in different ways. Celiac testing looks at the autoimmune mediated reaction component while the food safe test looks at a delayed food sensitivity reaction.

Instructions

Fasting is not required for this test. Take all medications as prescribed.

Note

If a person stops eating foods with gluten (for typically 3-6 months) before being tested, the results may be negative for celiac disease, even if the disease is present. If your doctor suspects that you have celiac disease and you are already on a gluten-free diet for several months, he or she may suggest adding wheat/gluten back into your diet before testing.

References:

1. Leffler, D.A. & Schuppan, D. (2010). Update on serologic testing in celiac disease. Am J Gastroenterol. 105(12):2520-4.
2. Volta U, Fabbri A, Parisi C, et al. Old and new serological tests for celiac disease screening. Expert Rev Gastroenterol Hepatol. 2010;4(1):31-35.
3. Leffler, D.A. (2011). Celiac disease diagnosis and management: A 46-year-old woman with anemia. JAMA, 306(14), 1582-1592.