Helicobacter pylori and duodenal ulcer: Evidence for a histamine pathways-involving link

Objectives: A 'gastrin link' has been suggested to explain the statistically relevant association between Helicobacter pylori and duodenal ulcer. Given the well known, although not entirely clarified, relationships between gastrin and histamine, the purpose of this study was to assess whether gastric mucosal histamine pathways and, more specifically, histamine- storing cells are involved in the Helicobacter pylori-duodenal ulcer route. Methods: Fasting serum gastrin, gastric mucosal histamine content, and mucosal density of both enterochromaffin-like cells and mast cells were compared in 11 H. pylori-positive, non-duodenal ulcer subjects, in 16 duodenal ulcer patients (all H. pylori positive), and in 11 H. pylori- negative control subjects. Results: Fasting serum gastrin concentration and mucosal histamine content were significantly higher in the duodenal ulcer group than in controls, whereas H. pylori-positive, non-ulcer subjects had values that were intermediate between those of the other two groups. Enterochromaffin-like cell density was significantly greater in duodenal ulcer patients than in the other groups. Conclusions: These results demonstrate the involvement of histamine pathways in H. pylori infection and duodenal ulcer. The most original finding in this study was that enterochromaffin-like cell density is three times greater in duodenal ulcer patients than in H. pylori-positive, non-ulcer subjects. This could explain the previous report of an exaggerated acid response to gastrin in duodenal ulcer patients when compared with H. pylori-positive, non-ulcer subjects and thus provide further insight into the pathogenesis of ulcers.