Wine anaphylaxis in a German patient: IgE mediated allergy against a lipid

Background: Allergy to grapes has previously been reported rarely; and mainly in patients from Mediterranean countries. Recently, endochitinase 4 and a lipid transfer protein have been identified as the major allergens in grapes. The purpose of this case study was to identify the allergen responsible for severe anaphylactic reactions after consumption of wine, fresh grapes, and raisins in a German patient. Methods: Prick-to-prick tests, specific IgE and basophil activation test were evaluated. Specific IgE was analyzed by immunoblotting and an inhibition test for determination of cross-reactivity. The IgE binding band was subjected to N-terminal microsequencing. Results: Specific IgE to grape (f259) was 2,43 kU/l (class 2). Prick-to-prick tests were positive to fresh and heated white and blue grapes, to raisins, white and red wine, and an apple extract. The basophil activation test confirmed specific IgE to apple. Immunoblotting showed IgE binding to a 9 kDa protein which was completely inhibited by pre-incubation of the serum with recombinant cherry LTP Pru av 3. N-terminal sequencing identified this band as grape LTP. Conclusion: Our data show that severe fruit allergy not related to birch pollen allergy does exist outside the Mediterranean area and that sensitization to LTP can occur in Germany.