Gastritis associated with Crohn disease can be masked by Helicobacter pylori gastritis

Background: Crohn disease (CD) is typically associated with focal inflammatory infiltrations. It is, however, unclear to what extent this CD-associated gastritis is masked by Helicobacter pylori gastritis. Methods: One hundred and three patients with CD underwent upper endoscopy. Antrum and corpus biopsy specimens were obtained and histologically evaluated for the presence of CD gastritis or H. pylori gastritis. In patients infected with H. pylori, eradication of the organism was initiated with repeated endoscopy/histology 7 days after termination of therapy. Results: Thirty patients were infected by H. pylori. Definite diagnosis of CD gastritis was made in 4 patients, in contrast to 31 of the 73 patients with no H. pylori gastritis (P < 0.001). In 19 patients with either no (n = 13) or only suspected diagnosis of CD gastritis (n = 6), elimination of H. pylori enabled definite diagnosis of CD gastritis in 5 of 13 and 4 of 6 patients, respectively. Conclusion: Elimination of H. pylori facilitates the diagnosis of CD gastritis.