<prompt> H.pylori causes all except;Peptic ulcerMaltomaCarcinoid tumorGastric CA  <response>: H.pylori is gram negative bacteria, non sporing, micro aerophilic, extra cellular bacteria. H.pylori releases urease enzyme which conves urea to ammonia and ammonia stimulates G cells of stomach which in turn stimulates parietal cells and cause secretion of HCl and Hyperchlorydia. This acid travels into stomach duodenum and causes peptic ulcers. H.pylori is a type I carcinogen, which, if present in stomach or long term can cause cancer called MALTOMA Mucosa Associated Lymphoid Tumor, which is a B-type NHL. Also Know mc site of duodenal ulcer in duodenum: D1 If ulcer at atypical site like D2, suspect Zollinger Ellison Syndrome IOC for H. pylori: Urease test invasive procedure Urea breath test: test for eradication of infection S. ELISA: Screening test for H.Pylori 