Specific IgE antibodies to peanut in western Sweden -: has the occurrence of peanut allergy increased without an increase in consumption?

Background: Sensitization to peanut has seldom been investigated in Sweden. Therefore, all IgE-specific tests for peanut during a 5-year period were reviewed to study the relation between the levels of specific IgE antibody to peanut and age, sex, symptoms, and other atopic manifestations. Methods: All serum samples were analyzed for IgE antibodies to peanut in relation to sex, age, clinical reactions, and other food allergens. A subgroup was asked to answer a questionnaire about symptoms and atopic manifestations in relation to IgE antibody levels. Results: During the study period, 2417 tests were made for peanut. There was an increased prevalence of detectable IgE antibodies during the years studied. More than 80 individuals under 2 years of age were sensitized to peanut. In the subgroup, individuals with detectable IgE antibodies reported a shorter reaction time after eating peanuts than individuals with normal IgE antibody levels (P <0.05). Conclusions: The reaction pattern to peanuts in Sweden is similar to that in many other countries despite a reported steady and low consumption. The severity of symptoms was connected to age and IgE antibody level. Patients with normal or low IgE antibody levels were not always free of symptoms even though their risk of allergic symptoms was reduced.