What is the prevalence of H. pylori positive in patients with peptic ulcer disease?
About 80% of ulcers would be due to H. pylori (90% of duodenal ulcers and 605 of gastric). The bacteria causes inflamation of the lineing of the stomach/duedenum so it is no longer aduquatly protected from the acidic contents. It does NOT increase acid secretion. As for the the other 20% most are due to chronic use of NSAIDs. A few (though very rare in western countries) would be due to gastric cancer, and another rare cause is brain injury which can cause hypersecretion of stomach acid.
