Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 1 1 2000 01 15 17 19 A. Farhoudi N. Bazargan Z. Pourpak M. Movahedi M. Moin 2015 10 01 Helicobacter pylori, the most important cause of gastritis and peptic ulcer, has recently been associated with several extradigestive diseases. The aim of this study was to assess the prevalence of Helicobacter pylori infection and effects of bacterium eradication in 50 patients affected by idiopathic chronic urticaria. Helicobacter pylori was assessed by serology or biopsy and urease test or 13C urea breath test. Amoxicillin, bismuth subcitrate (Denol), metronidazole and cimetidine were given to infected patients for 2 weeks. The results of therapy were assessed by urea breath test six weeks after therapy. In response to treatment urticaria clinically regressed in 16 out of 24 patients (66.6%). Thus bacterium eradication was associated with a remission of urticaria symptoms, suggesting a possible role in the pathogenesis of this disorder. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/3 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/3/3