Objective: According to hygine hypothesis, exposure to infections and living in an unhygienic environment might prime the immune system and protect from development of allergic disorders. It was shown that exposure to foodborne or orofecal microbes were inversely related to the allergic diseases compared to airborne viruses. In this study we aimed to evaluate and compare the presence of allergic diseases in patients with and without Helicobacter pylori infection.

Materials and Methods: The study was carried out on 188 patients between ages of 3 and 18 years who were performed urea breath test with a suspician of H. pylori infection. History of presenting symptoms and presence of personal and familial asthma and allergic diseases were taken. Skin prick tests were done and complete blood count and serum immunoglobulin (IgA, IgM, IgG, IgE) levels were measured.

Results: A total of 188 patients with a mean age of 11.1 ± 3.7 years were enrolled in the study and 42% of them were male. Urea breath test was positive in 43.6% (n= 82) of patients. The rate of current allergic symptoms was 36.6% in children with H. pylori infection, while it was 51.9% in children without H. pylori infection (p= 0.037). In multiple logistic regression analysis H. pylori infection was the sole independent variable related to the presence of current allergic symptoms (RR= 2.23, %95 GA 1.13-4.40, p= 0.021).

Conclusion: There was no relation between the H. pylori infection and presence of life-long allergic diseaseas, however there was an inverse relation between H. pylori infection and current allergic symptoms.