Background: Asthma is a highly prevalent chronic respiratory disease in children. Moreover, the underlying causes of asthma exacerbation are important because they are effective in controlling and preventing asthma. The aim of this study was to evaluate the helicobacter pylori infection in controlled and uncontrolled asthmatic children compared to healthy children.

Methods: This case- control study was done on 120 children aged 6-14 years with moderate to severe asthma. Diagnosis of asthma was performed according to GINA criteria with respect to the history and clinical examination. In addition, 120 healthy children without asthma were considered as the control group. Helicobacter pylori stool antigen test was evaluated for all patients. In addition to the above information, age, sex, duration of asthma and gastrointestinal symptoms were also recorded for each patient. Data were analyzed using SPSS15, Chi-square and Fisher's exact test and T-test.

Results: The mean age of children in the asthmatic and healthy children was 8.3±2 and 8.5±2.3, respectively (p=0.479). Totally, 57.5% and 58.3% of children were boys in the control group, and in asthmatic group, respectively. Thirty percent of children in the control group and 8.3% of children with asthma were H. pylori positive (p=0.000). Mean duration of asthma in children with H. pylori positive (3.3±1.55) and H. pylori negative (3.33±1.56) stool antigen showed no significant difference (p=0.944).

Conclusions: The results of this study indicated that there was an inverse relation between helicobacter pylori infection and asthma.