Study On The Immunologic Mechanism Of Chrnonic Urticaria Caused By Helicobacter Pylori Infection

Objective: It have not been found the etiological factor in the most of Chronic urticaria (CU)which is considered as Chronic 'idiopathic' urticaria, while the key factor for therapy is to explore the etiological factor. Recently, Different studies have shown a sort of relationship between Helicobacter pylori (Hp) and CU because of the high prevalence of infection in patients with chronic urticaria, and the remission of the skin lesions after eradication therapy. Hp would be recognized by infected host, which would induce immunologic response, disturb balance of Th1/Th2 and induces diseases. In the study, we investigated 1. the positive rate of anti-Hp IgG in patients with CU, 2. the production of Th1-type cytokine IL-4 and Th2-type cytokine IFN-γ from PBMC in patients with chronic urticaria stimulated with Hp in order to understand the role of Hp in chronic urticaria pathogenesis. Methods: 1. Hp -specific IgG antibody response was determined by ELISA in 80 patients with chronic urticaria and 50 healthy controls. 2. The levels of IFN-γ, IL-4 in the supernatants of Peripheral blood mononuclear cell (PBMC) stimulated with sonicated Hp or PHA were measured by ELISA In 25chronic urticaria patients (14 seropositive /11 seronegative for Hp) and 18 healthy controls (9 seropositive /9 seronegative) .Results: 1. 68.75% patients with Chronic urticaria are Hp -specific IgG antibody positive, which is significantly higher than healthy controls (P<0.005). 2. In healthy group, Hp induced IFN-γ production ,whose levers were no significant differences between the seropositive and the seronegative, and litter IL-4 was measured ;In chronic urticaria group ,both Hp and PHA induced the significant higher levels of IL-4 production than those in the healthy group (P＜0.01) ,while the levels of IFN-γ were significant lower than the healthy group or no significant differences between them. 3.In the seropositive patients with chronic urticaria, Hp induced more IL-4 production compare to the seronegtive (P=0.052),while PHA induced more IL-4 production too ,but the score of P increased (P=0.34). Conclusions: Conclusions: 1.there is a sort of relationship between Hp infection and Chronic urticaria .2.Th2 –type cellular immune response dominates in Chronic urticaria.3. Hp infection might play a role in the onset of chronic urticaria by disturbing the balance of Th1/Th2, and inducing cellular immune response shift toTh2-type ,however which still can not demonstrate that Hp is the pathogen of chronic urticaria.