Gluten sensitivity beyond Celiac Disease

S2050 Gluten Sensitivity: Beyond Celiac Disease Raffaella Tortora, Paola Iovino, Ilaria Russo, Fabiana Zingone, Pietro Capone, Antonella Ranaudo, Paolo Andreozzi, Carolina Ciacci Gluten sensitivity is a new concept to define a condition of some morphological, immunological and functional disorders that withdraw with a gluten free diet in patients HLADQ2/ DQ8 positive, with negative gluten-specific autoantibodies and without histological characteristic of celiac disease (CD). Aim of this study was to characterize in the patients with gluten sensitivity the mucosal responses during an In Vitro gluten challenge (iVGC) with exposition to gliadinin comparison with celiac patients on gluten-free diet. Methods: 50 CD patients on gluten-free diet and 59 patients reporting gluten sensitivity and negative specific antibodies underwent upper endoscopy and multiple jejunal biopsies. Mucosa was placed on organ culture dish for 3 and 24 hours, challenged with peptic-tryptic digest from wheat which, in CD mucosa, is known to induce expression of markers of immunological activation (CD3, CD25, CD69, PY99). In fact, in all CD patients iVGC was able to show mucosal inflammation upon gliadin challenge. Basal histology showed normal mucosa in 12 gluten sensitive patients, increased IELs and mucosal alteration in 47 (Marsh 1: 36 patients; Marsh 2: 7 patients; Marsh 3: 4 patients). In 10 gluten sensitive patients iVGC showed mild mucosa inflammation (modest CD3/CD25 increase, CD69 and PY99 increase) as for some CD patients, in 47 mucosa showed no signs of inflammation upon gliadin challenge, and in 2 iVGC was not conclusive because inducing a mild increase of some markers but not all. In conclusion: in 79.6 % of patients reporting gastrointestinal symptoms after gluten ingestion iVGC was not able to disclose mucosal inflammation after gliadin challenge. In 16.9%, however, iVGC disclosed a mild inflammation following gliadin contact. Our data for the first time demonstrate for a small percentage of gluten sensitive patients an immunological activation of intestinal mucosa secondary to gliadin exposure