DIAGNOSTIC WORK-UP FOR FOOD-DEPENDENT, EXERCISE-INDUCED ANAPHYLAXIS

Fourteen patients with suspected food-dependent, exercise-induced anap hylaxis (EIAn) were subjected to prick tests with commercial food extr acts and common airborne allergens, prick + prick tests with fresh foo ds, determination of total IgE levels, and specific IgE for 31 foods ( CAP System FEIA RAST). All were positive for two or more foods; 10 pre sented hypersensitivity to 11 or more foods. On the basis of these fin dings, history data, and responses to food-exercise challenges (treadm ill stress tests 90 min after meals containing none of the suspected f oods and none associated with skin-test and/or PAST positivity) and su spected food-exercise challenges (SFECs - administered after meals con taining the suspected food), three patients were diagnosed as having s pecific food-dependent EIAn (for wheat in two cases, tomato in one). I n nine others, the presence of specific IgE for numerous foods (includ ing those suspected on the basis of histories and utilized in the SFEC s) suggests involvement of specific food hypersensitivity, although SF EC confirmation could not be obtained. Avoidance of all foods associat ed with test positivity 4 h before exercise has prevented all further EIAn episodes in these 12 patients. In two others, the reactions did n ot appear to be related to IgE directed against specific food allergen s, and these subjects have eliminated further reactions by avoiding al l meals for the 4 h preceding exercise. These findings emphasize the i mportance of allergologic testing with a wide panel of food allergens (including foods used for seasoning, such as garlic or parsley) in all patients with suspected food-dependent EIAn. Prick + prick tests with fresh foods and the CAP System PAST disclosed numerous hypersensitivi ties.