Anisakis simplex allergy after eating chicken meat.

BACKGROUND Allergic reactions to food can be produced by contaminants that induce sensitization. Among these, Anisakis simplex can cause seafood infestation, and allergic symptoms (urticaria-angioedema, anaphylaxis, and asthma) can follow the eating or handling of affected fish. Although seafood is the principal source of human infections by this parasite, we have found allergic symptoms in 8 patients previously diagnosed as having A simplex sensitization after they ate chicken meat. Chicken feed usually has a high proportion of fishmeal, which might possibly be contaminated by this nematode. OBJECTIVE The aim of our study was to determine whether parasite proteins present in chicken meat could be responsible for the symptoms reported by these subjects. METHODS We carried out in vivo tests (prick, bronchial challenge, and double-blind placebo-controlled challenge with meat chicken) in these 8 patients. We performed immunoblotting using the sera from the 8 patients and controls in order to detect A simplex sensitization. We also investigated the presence of A simplex proteins in sera from chickens fed with fishmeal and in other sera from chickens fed only with cereals. We excluded sensitization to other chicken nematodes by serologic methods. RESULTS All 8 patients presented positive prick and challenges to A simplex. When we used serum from chickens fed with fishmeal as the antigen in blotting, patients 3, 4, 5, 6, 7, and 8 recognized a band of 16 kd, also obtained when using pools of fish-shellfish and A simplex larva. No detection was observed with sera from chickens fed with only cereals. CONCLUSION We provide evidence, based on in vivo and in vitro tests, that subjects highly sensitized to A simplex can detect the presence of Anisakis species allergens in chicken meat.