Focal gastric inflammatory infiltrates in inflammatory bowel diseases: prevalence, immunohistochemical characteristics, and diagnostic role

OBJECTIVES: To date, few studies have evaluated gastric histology in patients with inflammatory bowel disease (IBD). The aim of this prospective controlled study was to establish the frequency of focal gastritis in Crohn's disease (CD) and ulcerative colitis (UC) patients, as well as to evaluate its immunohistochemical characteristics and clinicoanatomical determinants. METHODS: We evaluated 141 consecutive patients with known CD of the large and/or small bowel, 79 patients with UC, and 141 CD- and UC-free controls; all underwent upper gastrointestinal (GI) endoscopy and 13C urea-breath test. Biopsy specimens taken from the antrum, angulus, and gastric body were evaluated by histology and immunohistochemistry. A series of variables, including CD activity index, duration, extent and location of disease, intestinal resection, number of recurrences, and previous and current medical therapy, as well as the presence of dyspeptic symptoms and mucosal lesions at endoscopy, were determined in all CD patients and correlated with the presence or absence of focal gastritis. RESULTS: Helicobacter pylori-associated gastritis was found in 47 patients with CD (33%), in 37 patients with UC (47%), and in 60% of CD-/UC-free controls (p < 0.01). In H. pylori-negative CD patients focal gastritis was found in 43% of cases (40/94), compared with 12% (5/42) of UC patients and 19% (11/57) of controls (p < 0.05). Specificity and positive predictive value of focal gastritis in CD were 84% and 71%, respectively. It was characterized by a focal perifoveolar or periglandular lymphomonocytic infiltrate, with CD8+/CD4+ cells predominant both in CD and UC patients. There were no significant correlations between the occurrence of focal gastritis and any clinicoanatomical CD features. CONCLUSIONS: Focal gastritis is relatively common in CD patients although it is not exclusive to this condition. Its recognition could be useful in the diagnostic workup of any patient with suspected or indeterminate inflammatory bowel disease, as it makes a diagnosis of CD more likely.