ABC of the upper gastrointestinal tract: Pathophysiology of duodenal and gastric ulcer and gastric cancer

摘要

Duodenal and gastric ulcers and gastric cancer are common and serious diseases but occur in only a minority of people infected with Helicobacter pylori. Mass eradication of H pylori is impractical because of the cost and the danger of generating antibiotic resistance, so we need to know how to target prophylaxis. Knowledge of the mechanisms that lead to ulcer formation or to gastric cancer in the presence of H pylori infection is therefore valuable. Various factors affect the outcome of H pylori infection, including the host response and particularly the extent and severity of gastric inflammation and thus the amount of acid secreted by parietal cells. H pylori can elevate acid secretion in people who develop duodenal ulcers, decrease acid through gastric atrophy in those who develop gastric ulcers or cancer, and leave add secretion largely unchanged in those who do not develop these diseases.