Understanding how gluten causes symptoms in coeliac disease (CD) and non-coeliac gluten sensitivity (NCGS)

This is a single-blind, placebo-controlled cross-over gluten challenge study to assess symptoms and symptom biomarkers in the blood and small intestine after ingestion of gluten or placebo in patients with coeliac disease (CD), non-coeliac gluten sensitivity (NCGS) and unaffected controls. 3 grams of gluten protein or matched placebo will be administered via oral capsules. Exact dose will be fixed for all patients and allocation (gluten or placebo) will not be revealed to the participant. Each participant will undertake two single-dose challenges with a minimum 4-week wash-out period between interventions (one placebo, one gluten). Gluten and placebo will both be food-grade. This will be administered and supervised by a Clinical Coordinator and/or Gastroenterologist. Assessments may include: blood collection and gastroscopy with duodenal biopsies before and within 6 hours after gluten/placebo challenge and hourly symptom monitoring using a patient-reported outcome measure. Recruitment, blood collection and gluten challenges will be undertaken at the Clinical Translation Centre, Walter and Eliza Hall Institute (CTC WEHI) or Clinical Translation Centre at the Royal Melbourne Hospital (CTC RMH). Gastroscopies will be performed in the Royal Melbourne Hospital (RMH).