Background
Helicobacter pylori (H. Pylori) infection is typically acquired in the early decades of life and, if not cleared, is associated with gastritis and hypergastrinaemia [1]. Similarly, Multiple Endocrine Neoplasia Type 1 (MEN 1) predisposes gene carriers to a 30-40% risk of developing either hypergastrinaemia or overt Zollinger-Ellison Syndrome (ZES). Gastrinomas in MEN 1 are typically multifocal submucosal duodenal lesions. Further, H. Pylori incidence is augmented by the acid environment which prevails in MEN 1 and ZES.
Objective
To determine if a relationship exists between H. Pylori IgG seropositivity and hypergastrinaemia /ZES in MEN 1.
Methods
A retrospective longitudinal cohort study involving 99 individuals with MEN 1 who underwent fasting serum gastrin and H pylori serum IgG immunoassay assessment (mean age 43.9±17.9 years, 66.0% female). All patients were confirmed to have the Tasman 1 MEN1 gene mutation. ZES-range hypergastrinaemia was defined as gastrin >10-fold normal elevated.
Results
Of the 99 patients tested for H pylori, 36 (36.4%) of cases were IgG seropositive. Serum gastrin was elevated greater than one-fold normal in 29 (80.6%), five-fold normal in 17 (47.2%) and ten-fold normal in 11 (30.6%) of the H pylori IgG positive patients. Of the 63 patients with negative H pylori serology, serum gastrin was elevated greater than one-fold normal in 30 (47.6%), five-fold normal in 6 (9.5%) and ten-fold normal in 2 (3.2%) patients. Of those patients with ZES-range serum gastrin elevation, 11 of 13 (85%) were H pylori IgG seropositive.
Conclusion
Severe hypergastrinaemia and ZES was strongly associated with H. Pylori seropositivity in this study. Chronic mild-moderate H. Pylori-related hypergastrinaemia may have the potential to stimulate pathogenesis of gastrinoma in MEN 1 by promoting neuroendocrine cell hyperplasia. This warrants further investigation.