Helicobacter pylori (H.pylori) can cause a wide array of gastric disorders such as chronic gastritis, peptic ulcer, and gastric cancer. In fact recent studies and accumulating evidence implicate helicobacter pylori in various extra intestinal autoimmune mediated diseases such as:chronic urticaria, psoriasis, schonleinhenoch purpura, behcet's disease, immune mediated thrombocytopenic purpura, food allergy, and multiple sclerosis, which will be discussed here. Various immunopathological theories was conceived in an effort to clarify this relationship between the helicobacter pylori and autoimmune diseases.However even these theories are not bases on solid experimental data. But helicobacter pylori eradication was shown to improve symptoms of these diseases and improving the quality of life.I wrote this research to arise some ambiguity in this topic and to be a constant draw attention to this topic.

Keywords : H. pylori, Autoimmune Disease, Chronic Urticaria, Immunomodulation, H. pylori eradication.