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 r eviewed to study the relation between the levels of specific IgE antibody t o peanut and age, sex, symptoms, and other atopic manifestations. Methods: All serum samples were analyzed for IgE antibodies to peanut in re lation to sex, age, clinical reactions, and other food allergens. A subgrou p was asked to answer a questionnaire about symptoms and atopic manifestati ons in relation to IgE antibody levels. Results: During the study period, 2417 tests were made for peanut. There wa s an increased prevalence of detectable IgE antibodies during the years stu died. More than 80 individuals under 2 years of age were sensitized to pean ut. 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 i n many other countries despite a reported steady and low consumption. The s everity of symptoms was connected to age and IgE antibody level. Patients w ith normal or low IgE antibody levels were not always free of symptoms even though their risk of allergic symptoms was reduced.