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.