S1259 Intestinal Deposits of IgA Anti-Tissue Transglutaminase Antibodies in Children with Potential Coeliac Disease

Abstract

Objective. Anti-tissue transglutaminase (anti-TG2) IgA utoantibodies are detectable in serum of the great majorty of patients with untreated coeliac disease (CD). Many vidence suggest that they are primarily produced in the ntestinal mucosa. The detection of IgA anti-TG2 intestinal eposits is proposed to be a specific and sensitive tool for the iagnosis of CD. The aim of this work is to investigate the resence of anti-TG2 IgA autoantibodies in the small intesine of patients with potential CD (subjects with presence n the serum of anti-endomysium antibodies (EMA) and/or igh levels of anti-TG2, and a normal intestinal mucosa). The resence of intestinal anti-TG2 IgA has been related to the volution to severe enteropathy. Methods. The study involved 27 children with potential D (18 F and 9 M, median age 8 years and 3 months). All atients were asymptomatic and showed HLA consistent with D; they continued a gluten free diet and underwent clinical nd laboratory controls every 6 months, and a second biopsy fter 2 years. Anti-TG2 IgA intestinal deposits were detected y double immunofluorescence and confocal microscopy. Results. 20/27 (74%) patients showed anti-TG2 IgA ntestinal deposits at the beginning of the study. After two ears 12/20 still presented a normal intestinal mucosa with gA anti-TG2 intestinal deposits, while in 4 cases such eposits were not observed even if the patients continued o present a positive serology for CD and a normal mucosa. inally, 4/20 (20%) children with IgA deposits presented, t the time of the second biopsy, villous atrophy. Of the even patients who were negative for anti-TG2 IgA intestinal eposits at the time of the first biopsy, 4/7 were confirmed gain negative for those deposits after 2 years; 3/7 become ositive and one of them developed villous atrophy. Conclusions. Most patients with potential CD presented nti-TG2 IgA intestinal deposits, but not always there was orrespondence with the presence in the serum. Only 4/20 atients with potential CD, who showed intestinal deposits f anti-TG2 IgA at the time of the diagnosis, developed vilous atrophy. In patients with potential CD, after two years f follow-up, the presence of IgA anti-TG2 deposits is not redictive of the development of the mucosal atrophy.