Gluten Challenge for Accurate Celiac Disease Testing
January 19, 2012
Question
I’ve been gluten-free for a while and I’m getting tested for celiac disease. How much gluten should I consume before getting the celiac blood panel?
Answer
As listed in Real Life with Celiac Disease, here are the guidelines for a gluten challenge:
- Perform basic laboratory testing for IgA-tTG and total IgA level.
- If tTG is elevated, proceed to step 5.
- If tTG is within normal limits and there is a history of severe symptoms with gluten exposure, consider HLA-DQ2 or -DQ8 typing (genetic testing). Be cautious with gluten challenge if positive for HLA-DQ2 or -DQ8.
- If tTG is within normal limits and there is no history of severe symptoms with gluten exposure, begin gluten challenge with one regular cracker or ¼ slice of regular bread. Double this every 1-3 days until significant symptoms develop or until you are eating the equivalent of 4 slices of bread or 2 cups/servings of pasta per day. Continue a full gluten-containing diet for 2 months before being tested for celiac disease. Note: The amount and duration of gluten ingestion can be altered depending on the severity of symptoms.
- Perform endoscopy with duodenal biopsies and check IgA-tTG.
- If biopsies are negative for celiac disease, continue a gluten-containing diet. Recheck tTG in 3-6 months or if symptoms develop. Repeat endoscopy with biopsy if tTG is elevated.
Sincerely,
Melinda Dennis, MS, RD, LDN
References
Leffler, D. (2010). Chapter 8: Gluten Intolerance: You Mean I Don’t Have Celiac Disease? In M. Dennis & D. Leffler. Real Life with Celiac Disease: Troubleshooting and Thriving Gluten Free. (p. 55). Bethesda, MD: AGA Press.