Gastroduodenal mucosa in microscopic colitis.

Background. We have assessed gastroduodenal, endoscopical and histopathological findings in a series of patients with microscopic colitis (MC). Methods. We studied 75 patients with MC, 27 with collagenous colitis (CC) and 48 with lymphocytic colitis (LC), and 60 controls. Data of endoscopical findings were collected and biopsies were assessed. Results. Helicobacter pylori infection rate was 15% in MC and 28% in the controls (p == 0.088). Age at diagnosis of MC was higher in H. pylori positive than negative patients (63.4 +/-+/- 9.6 vs. 54.4 +/-+/- 13.1 years; p == 0.034). Gastric endoscopic erosions were more prevalent in CC than in LC (25.9% vs. 6.2%; p == 0.030) and associated with thick body glands and antral predominance of gastritis in H. pylori positive patients. Rates of focal gastritis (5.6% vs. 6.9%) and lymphocytic gastritis (5.6% vs. 10%) were similar in MC and controls. LC was associated with gastric epithelial lymphocytosis and lymphocytic gastritis. Fifteen patients (20%) had celiac disease. Conclusions. Unlike LC, CC is associated with endoscopic erosions, likely related with the high acid secretion capacity as indicated by the ample body glands and antral predominance of gastritis in H. pylori associated cases of CC. The presence of some divergent gastroduodenal features in LC and CC, and in comparison with those reported in inflammatory bowel disease (IBD), supports the concept that these two conditions differ not only from IBD but also from each other. The findings also suggest the presence of pathogenetic links between colorectal and gastroduodenal abnormalities.