Food as a trigger for abdominal angioedema attacks in patients with hereditary angioedema

BACKGROUND: Hereditary angioedema with C1 inhibitor deficiency (C1-INH-HAE) is a rare inherited disease. In most HAE-affected subjects, defined trigger factors precede angioedema attacks. Mechanisms of how trigger factors stimulate the contact activation pathway with bradykinin generation are not well elucidated. In recent studies, hypersensitivity reactions and food were stated as relevant triggers. We investigated HAE affected people for possible hypersensitivity reactions or intolerances and their relation in triggering angioedema attacks. METHODS: A questionnaire was filled in, recording date of birth, gender, and self-reported angioedema attacks associated with the ingestion of foodstuffs, administration of drugs, hymenoptera stings and hypersensitivity reactions against inhalation allergens. All participants performed a skin prick test against inhalation allergens and food. In patients who stated an association of possible hypersensitivity with angioedema, a serological ImmunoCAP test was also performed. RESULTS: From the 27 women and 15 men analyzed, 79% stated trigger factors. From those food was mentioned in 36%. The suspected food included tomato, green salad, fish, citrus fruits, apple, onion, garlic, cheese, chili, kiwi, milk, tree nuts, strawberry, pineapple, shrimps, bread, banana, leek, chicken and alcohol, and were associated with abdominal angioedema. Neither the skin prick test nor the ImmunoCAP-test turned out positive for the tested food allergens. CONCLUSION: Food seems to be a relevant trigger factor, causing angioedema in HAE affected patients. The reason, however, is not IgE-mediated hypersensitivity, but most probably an intolerance reaction to food products.