The aetiology of the atopic conditions angioedema (AE) and chronic urticaria (CU) has hitherto been obscure with suggestions to allergy or other hypersensitivity as the cause. The aim of this study was to test the hypothesis of food intolerance being associated with AE and CU. 52 patients, 39 females and 13 males with a median age of 48 yrs (range: 6-83) and a median duration of disease of 6 yrs (range 1-61) were included. The patients, none of them deficient of C1-esterase inhibitor had oropharyngeal symptoms at least twice a month and classical skin eruptions at least twice a week. Follow-up (n=51) was at least 6 months. The following methods were applied: RAST against 10 airborne and 8 common food antigens; total IgE and eosinophil counts and the computer controlled cellular test for food sensitivity Alcat Test against 100 foods.

Total IgE and eosinophils were raised in 6 and 3 cases respectively. RAST-airborne and RAST-food were Positive in 7 and 4 cases, respectively, and all patients were reactive in Alcat Test against 8-29 foods. Individual diets comprising Alcat Test-non reactive foods eliminated from RAST-positive foods and food-additives resulted in total remission in 45 individuals, remission of AE but not CU in 5 and failure in 1 case. AE being potentially lethal oral challenges were not applied due to ethics.

High clinical significance also at long-term follow-up was obtained in severe AE and CU by applying the results of Alcat Test, whereas IgE-mediated allergy play a minor role.