Histological features of nodular gastritis and its endoscopic classification

OBJECTIVES: To clarify the histological features and endoscopic classifications of nodular gastritis (NG). METHODS: Overall 40 996 patients who had undergone an upper gastrointestinal endoscopy were enrolled. NG is defined as a uniform and diffuse protrusion from the antrum to angulus, which has two types at endoscopy: nodular (N) and granular (G). Three biopsy specimens were taken from the antrum, angulus and corpus. The histological features were evaluated using the updated Sydney System (USS). The topography of gastritis (antrum‐predominant, pangastritis or corpus‐predominant) and the prevalence of lymphoid follicles were also investigated. RESULTS: Overall 89 patients (0.22%) were diagnosed with NG, which tended to decrease in prevalence over age and predominantly affected women. All the patients were Helicobacter pylori‐positive. Among these, 65 patients underwent biopsy. Activity and inflammation were mostly moderate or severe, while intestinal metaplasia and atrophy were mostly absent at all three sites. Pangastritis was the most frequent (72%) type of gastritis. Lymphoid follicles were found in 69% at the antrum, 65% at the angulus and 51% at the corpus. There were no significant differences between N and G types in clinical features, USS scores, topography of gastritis, and prevalence of lymphoid follicles. CONCLUSIONS: Atrophy and intestinal metaplasia are rare but activity and chronic inflammation are severe at the antrum, angulus and corpus in NG. Pangastritis is the commonest type of gastritis. Lymphoid follicles affect everything up to the upper corpus, contrary to endoscopic protrusion found only at angulus. There was no correlation with pathological features between N and G types.