Change in Permeability of the Small Intestine After Treatment With Gluten

A Pilot Study Barrier Function, Intestinal Permeability and Tight Junction Expression in Gluten Sensitive Patients With Functional Gastrointestinal Disorders

The overall hypothesis of this research study is that gluten intake alters intestinal barrier function in patients with Irritable Bowel Syndrome (IBS) diarrhea who also exhibit non-celiac gluten sensitivity (NCGS).

The specific aim of this hypothesis-generating, pilot study is to randomize (like the flip of a coin) patients who have Non Celiac Gluten Sensitivity to a 4-week Gluten-containing diet (GCD) or to a Gluten free diet (GFD). The study will evaluate small bowel (SB) permeability functionally (2-sugar differential excretion), morphologically, using probe-based confocal laser to evaluate the small intestinal, as well as molecularly, using tight junction (TJ) messenger RNA (mRNA) expression in small bowel mucosa in response to the different diets.

Inclusion Criteria:

1. Non celiac gluten sensitive patients with a functional bowel disorder
2. Age 18 to 70 years.

Exclusion Criteria:

1. Positive serum tissue transglutaminase (TTG) Immunoglobulin A (IgA) positive or medical record of small bowel biopsy suggestive of celiac disease.
2. Use of tobacco products within the past 6 months (since nicotine may affect intestinal permeability).
3. Abdominal surgeries (except appendectomy, cholecystectomy and vaginal hysterectomy or tubal ligation)
4. Use of Nonsteroidal Anti-inflammatory Drugs(NSAIDs) or aspirin within the past week (since Nonsteroidal Anti-inflammatory Drugs (NSAIDs) affect intestinal permeability).
5. Use of oral corticosteroids within the previous 6 weeks.
6. Ingestion of artificial sweeteners such as Sucralose, Nutrasweet ™ (aspartame), lactulose or mannitol 2 days before the study tests begins, e.g., foods to be avoided are sugarless gums or mints and diet soda.
7. Bleeding disorders or medications that increase risk of bleeding from mucosal biopsies.
8. High anxiety or depression score (>11 on each subscale) on the Hospital Anxiety Depression Score questionnaire.
9. Known allergy to fluorescein.