Pan-Gastrointestinal Tract Mucosal Pathologies in Patients with Celiac Disease with the Demonstration of IgA Anti-Transglutaminase Mucosal Deposits: A Case-Control Study

Background While celiac disease (CeD) is considered to affect primarily the small intestine, pathological changes in other parts of the gastrointestinal tract (GIT) are also known to occur. IgA anti-tissue transglutaminase-2 antibody (anti-TG2 Ab) deposits at the site of involvement is one of the methods to establish CeD-related tissue pathology. Aims To explore the utility of IgA anti-TG2 Ab deposits in pan-gastrointestinal mucosal biopsies as evidence of CeD-related pathologies. Methods Forty-two treatment-naive patients with CeD and 45 patients with irritable bowel syndrome were included as cases and controls, respectively. Mucosal biopsies were collected from the esophagus, stomach, duodenum, and rectosigmoid regions at baseline from cases and controls, and additionally after 6-months of gluten-free diet in cases. All biopsies were evaluated for histological changes and subjected to dual-color immunohistochemical staining for identifying IgA anti-TG2 Ab deposits. Results Significantly higher number of patients with CeD had lymphocytic esophagitis (9.7% vs. 0%, P = 0.05), lymphocytic gastritis (35% vs. 8.8%, P < 0.01) and lymphocytic colitis (17.4% vs. 0%, P < 0.05) than that in controls. IgA anti-TG2 Ab deposits were observed in significantly more numbers in esophagus (30.9% vs. 6%, P < 0.001), stomach (62.2% vs. 9.3%, P < 0.01), duodenum (88.5% vs. 0%, P < 0.001) and rectum (17.4% vs. 0%, P < 0.05) than that in controls. There was a decline, but not statistically significant, in severity of lymphocytosis and intensity of IgA anti-TG2 Ab deposits in follow-up biopsies. Conclusion Significantly higher number of patients with CeD had evidence of lymphocytic infiltration and IgA anti-TG2 deposits along GIT suggesting that CeD affects other parts of GIT.