Background and study aims: The incidence of Helicobacter pylori infection in Japan is high. Unlike the case in Western countries, H. pylori-induced gastritis in Japanese patients has a tendency to spread to the corpus. H. pylori-induced gastritis is characterized by a number of specific endoscopic findings. In a previous study, the endoscopic features and a magnified view of the gastric mucosa of the corpus of H. pylori-negative normal stomach were described. This report describes the specific histological features and magnified views of the H. pylori-negative stomach and compares them with those seen during H. pylori-induced gastritis.
Patients and methods: The anterior wall or greater curvature of the middle body of the stomachs of 297 patients were observed by magnifying endoscopy (x 80). Forceps biopsy was performed at the following locations: i) the magnified site, for histological examination; ii) the antral mucosa, for culture/urease test, and histology; and iii) greater curvature of the upper body for culture/urease test.
Results: 72 patients were diagnosed as having H. pylori-negative normal stomach and 225 as having H. pylori-positive gastritis. The magnified views were classified into four types: i) collecting venules, with true capillaries forming a network, and gastric pits resembling pinholes (type Z-0; n = 80); ii) irregular true capillaries but no collecting venules observed (type Z-1; n = 36); iii) white gastric pits and sulci, with neither collecting venules nor true capillaries being seen (Z-2; n = 110); and iv) dilated pits with surrounding redness (Z-3; n = 71). All cases of H. pylori-negative normal stomach were type Z-0, whereas H. pylori-induced gastritis was present in all cases where the classification was Z-1, Z-2, or Z-3. Type Z-0 differed significantly from types Z-1, Z-2, and Z-3 with regard to the grade of inflammation, activity, and presence of H. pylori.
Conclusions: Collecting venules and true capillaries forming a network with gastric pits in the center (type Z-0) were observed in the H. pylori-negative normal mucosa. The magnified views of H. pylori-related gastritis clearly differed from type Z-0.