Grape anaphylaxis.

Grape allergy is particularly rare in spite of the vast extension of Vitis vinifera cultivation on all continents. We report on the case of a 28-year-old woman who presented with allergic systemic reaction after eating white grapes (Vitis vinifera). She complained of two severe episodes of anaphylaxis after eating grapes, with generalized pruritus, acute generalized urticaria, facial swelling, lip and oropharingeal angioedema, and dysphagia. Both the episodes were treated at the Emergency Room level, with parenteral administration of corticosteroids and antihistamines. Skin prick tests with commercial extract of grapes provided a negative result, while prick by prick procedure performed with white grapes and white grape juice yielded a positive result. Grape-specific serum IgE were also detected. We conclude that in the diagnosis of grape allergy the currently available commercial extracts might not be completely reliable and the prick-by-prick procedure with fresh grapes should always be performed.