[3 cases of food-dependent exercise-induced anaphylaxis in which aspirin intake exacerbated anaphylactic symptoms]

Exercise-induced anaphylaxis (EIAn) is a distinct form of physical allergy. As one of the predisposing factors of EIAn, food intake is often cited, and such cases are classified as food-dependent EIAn. Another factor reported is the administration of drugs. Recently we had 3 patients with food-dependent EIAn who showed more severe symptoms when they took aspirin orally. None of them had shown symptoms when they took aspirin alone. Symptoms were provoked only when they took aspirin for common cold, headache or toothache followed by certain foods and exercise. Two out of the 3 patients had experienced food-dependent EIAn before. However, after taking aspirin, their anaphylactic symptoms were more severe with more slight degree of exercise. Results of exercise challenge by treadmill showed that exercise alone induced an increase in plasma histamine concentrations in 2 out of the 3 patients 5 to 15 minutes after the challenge. These data suggest the possibility that our patients have an increased histamine releasability from mast cells responding to exercise, and that aspirin intake might enhance the process.