ANISAKIS SIMPLEX INDUCES NOT ONLY ANISAKIASIS - REPORT ON 28 CASES OFALLERGY CAUSED BY THIS NEMATODE

Anisakis simplex R., parasitizes several sea-fish and cephalopods. Thi s parasite induces not only anisakiasis but also anaphylactic reaction s, as has recently been confirmed. We present 28 patients with immedia te hypersensitivity to Anisakis simplex, developed after parasitized f ish ingestion. Each case was diagnosed by suggestive anamnesis, skin p rick tests with an A. simplex extract, specific IgE detection in serum (CAP System), and histamine release test. The clinical manifestations were urticaria/angioedema in all 28 patients and respiratory arrest i n one. Paradoxically, the patients reported tolerance to ingestion of the same kind of fish between and after the allergic episodes. Type I hypersensitivity to A. simplex was demonstrated by a positive skin-pri ck test reaction, specific IgE detection in all cases and positive his tamine release in a representative case. Sensitization to the proteins of the fish themselves was ruled out by negative reactions of the sam e tests in all cases. It was also proven that the allergen/s involved may be resistant to cooking and deep freezing. Hence, anaphylactic rea ctions may result either from infection or, more frequently, from mere exposure to the allergen. The results confirm that A. simplex can dev elop IgE-mediated anaphylactic reactions, the clinical severity of whi ch was pronounced in the patients examined. Physicians must take into account that the consumption of parasitized fish may cause severe reac tions, even if fish of the same kind is subsequently tolerated. A high er frequency of reactions of this type can be expected in countries wh ere fish is a staple diet.