Comparison of allergic diseases and specific IgE antibodies in different parts of Japan.

We investigated the differences of allergic diseases and specific IgE antibodies to inhaled or ingested allergens between two cities in a Japanese pediatric population. One of the two cities is Itoman, which is a subtropical city in Okinawa prefecture; the other is Gifu, which is a Temperate Zone city in Gifu prefecture. The prevalence of asthma or wheezy bronchitis was significantly higher in Itoman; however, the prevalence of atopic dermatitis was significantly higher in Gifu. Furthermore, the positive percentages of specific IgE antibodies to inhaled allergens such as house dust, and Dermatophagoides farinae were higher in Itoman. The positive percentages of specific IgE antibodies to ingested allergens such as egg white, cow milk, and soybean were higher in Gifu. These results suggest that the differences in prevalence of allergic diseases and allergens may depend on differences in the triggering environmental factors between different parts of Japan.