Gastro-allergic anisakiasis as a consequence of simultaneous primary and secondary immune response.

Gastro-allergic anisakiasis has been reported as an entity in which an acute parasitism by Anisakis simplex is accompanied by an immunoglobulin (Ig)E-mediated systemic allergic reaction. Serum samples were obtained from 24 patients within 24 h after the onset of symptoms (day 0) and after 1 month (day 30) and in 13 patients after 6 months. Total IgE was assessed by the Imx method. Specific IgE was assessed by CAP-FEIA. Specific IgM, IgG, IgG4 and IgA antibodies were assessed by enzyme-linked immunosorbent assay against crude extract (CE) and excretory-secretory products (ESP). IgE immunoblotting (IB) was directed against CE or ESP (day 0 and day 30). We found a rise of total IgE, specific IgE, number of bands in IgE-IB, IgG and IgG4 between day 0 and day 30 with a fall to near basal levels after 6 months. IgM levels were highest at day 0, falling over the next 6 months and IgA levels remained almost unchanged. Correlation studies revealed a parallel stimulation of nearly all Ig isotypes, except IgM anti-ESP, whose antibody levels correlated negatively with specific IgG levels. We found an extension of the IgE antibody repertoire in IB. We conclude that the allergic IgE-mediated reaction in the course of gastro-allergic anisakiasis involves a parallel secondary Th2 type memory response and a primary immunologic stimulation of both Th2 and Th1 lymphocyte subsets against previously unrecognized antigens.