[Eradication therapy of Helicobacter pylori infection]

Helicobacter pylori(H. pylori) infection is recognized to be a pathogen of various gastro-duodenal diseases. Eradication therapy of H. pylori reduces the recurrence of gastro-duodenal ulcer, and improves gastritis histologically. Recently, proton pump inhibitor(PPI) based triple therapy, that combining PPI, clarithromycin, amoxicillin is widely accepted throughout the world, and shows high eradication rate which ranged about 80-90%. In Japan, one week triple therapy is recommended for the treatment of gastro-duodenal ulcer, though it is expected the improvement of recurrent peptic ulcer. In the present studies, the rate of clarithromycin resistant strains has been increased gradually, and this fact may lead to the development of failure of PPI based triple therapy. Another problem is suggested by several studies that gastro-esophageal reflux disease(GERD) may increase after successful eradication of H. pylori. Reflux esophagitis and Barrett's esophagus are recognized as precancerous lesion of esophageal adenocarcinoma, but the association of newly occurrence of GERD after H. pylori eradication and increase of esophageal adenocarcinoma is not clear. Merits and demerits of H. pylori eradication need to be observed carefully over a long term.