Anisakis simplex allergy and nephrotic syndrome.

Background: Anisakis simplex is a helmintic parasite of fish and shellfish that can induce in humans, after consumption, an immunoallergic response with multiorganic affectation, especially cutaneous (urticaria and angioedema), gastrointestinal and anaphylactic symptoms. Nephrotic syndrome can be produced by helmintic infection, especially schistosomiasis.

Objective: To report the unusual case of nephrotic syndrome associated to an allergic response to A. simplex.

Methods: A 60-year-old woman suffered from nephrotic syndrome three weeks after a generalized urticaria, angioedema and nauseas episode, following a raw anchovy's ingestion. Etiological study of nephrotic syndrome and urticaria/angioedema, cutaneous test, serum total and specific IgE determination, IgE-immunoblotting, and HLA typing were performed for diagnostic evaluation.

Results: Prick-test with A. simplex extract was positive. It was observed a significance increase of total IgE to the three weeks of anchovy's ingestion and then it diminished progressively. Specific IgE to A. simplex was > 100 UI/ml. Immunoblotting to A. simplex, revealed the existence of IgE-binding proteins with molecular mass ranging from 20 kDa to 99 kDa. Class I HLA expressed by the patient was type HLA-B12. Other secondary causes of nephrotic syndrome were carefully ruled out.

Conclusions: These data suggest, for the first time, the association between allergy to A. simplex and nephrotic syndrome.