Anti-tissue transglutaminase antibodies in inflammatory bowel disease: new evidence

Antitissue transglutaminase, previously held to be identical to antiendomysial antibodies in celiac sprue, has been reported in inflammatory bowel disease patients. To investigate these data further, we evaluated serum andintestinal antitissue transglutaminase in inflammatory bowel disease patients, with respect to the Crohns disease activity index and the integrated disease activity index. Study population comprised: 49 patients with Crohns disease and 29 patients with ulcerative colitis; 45 patients with celiac sprue and 85 autoimmune patients as disease controls; and 58 volunteers as healthy controls. Immunoglobulin A (IgA) antirecombinant human tissue transglutaminase and antiendomysial antibody detection in sera and fecal supernatants were performed. Adsorption of positive sera with recombinant human tissue transglutaminase were also performed. Marked increased antitissue transglutaminase concentrations were found in celiac sprue, while lowpositive values were also foundin Crohns disease and ulcerative colitis. Antiendomysial antibodies were detectable only in celiac sprue. Antigen adsorption resulted in a significant reduction of the antitissue transglutaminase either in celiac sprue or inflammatory bowel disease sera. A significant correlation between antitissue transglutaminase and Crohns disease activity index or integrated disease activity index scores was found. Antitissue transglutaminase was also detectable in fecal supernatants from inflammatory bowel disease patients. Data highlight that both circulating and intestinal antitissue transglutaminases are detectable in inflammatory bowel disease, and that they are related to disease activity. These features underline that, in addition to antitissue transglutaminase, an antiendomysial antibody test is necessary in the diagnostic workup of celiac sprue, especially in patients with known inflammatory bowel disease.