Gastric mucin expression in Helicobacter pylori-related, nonsteroidal anti-inflammatory drug-related and idiopathic ulcers

AIM： To determine the pattern of secreted mucin expression in Helicobacter pylori （H. pylori）-related, nonsteroidal anti-inflammatory drug （NSAID）-related and idiopathic gastric ulcers. METHODS： We randomly selected 92 patients with H. pylori-associated （n = 30）, NSAID-associated （n = 18）, combined H. pylori and NSAID-associated gastric ulcers （n = 24）, and patients with idiopathic gastric ulcers （n = 20）. Immunohistochemistry for T-cell CD4/CD8, andfor mucin 5AC （MUC5AC） and mucin 6 （MUC6）, was performed on sections of the mucosa from the ulcer margin. Inflammation score was assessed according to the Sydney system. RESULTS： MUC5AC was expressed on the surface epithelium （98.9%） and neck glands （98.9%） with minimal expression in the deep glands （6.5%）. MUC6 was strongly expressed in the deep glands （97.8%）, variable in the neck glands （19.6%） and absent in the surface epithelium （0%）. The pattern of mucin expression in idiopathic ulcer margins was not different from the expression in ulcers associated with H. pylori, NSAIDs, or combined H. pylori and NSAIDs. CD4/CD8 ratio was higher in H. pylori-positive patients （P = 0.009）. Idiopathic ulcers are associated with hospitalized patients and have higher bleeding and mortality rates. CONCLUSION： Idiopathic ulcers have a unique clinical profile. Gastric mucin expression in idiopathic gastric ulcers is unchanged compared with H. pylori and/or NSAID-associated ulcers.