title: Currant allergy and the Rosaceae-grass pollen allergy syndrome: a case report.
abstract: BACKGROUND
  Despite the increasing use of currants in culinary recipes, currant allergy has rarely been reported.
  
  
  OBJECTIVE
  To study a case of currant allergy and to explore cross-reactivity between grass pollen and Rosaceae family fruit allergens.
  
  
  METHODS
  Skin prick tests to pollen and skin prick-to-prick tests with currants and peach were performed. Specific IgE levels were determined using the CAP method. We prepared a protein extract of 0.1 mg/mL in phosphate-buffered saline using red currant in the presence of protease inhibitors. Immunoblot inhibition studies were performed to explore cross-reactivity between grass pollen and currant allergens.
  
  
  RESULTS
  Skin prick test results were positive to Dactylis, arizonic, and olive pollens. Results of skin prick-to-prick tests with fresh red and black currants were negative and positive, respectively, to peach. The specific IgE level was 5.7 KU/L to red currant and 2.92 KU/L to peach (CAP). Western blot analysis with red currant extract revealed specific IgE protein bands of 37 and 26 kDa. Preincubation of sera with extracts from red currant and peach inhibited both IgE bands, and preincubation with Dactylis pollen inhibited the 37-kDa band only.
  
  
  CONCLUSIONS
  We report a case of allergy to grass pollen with an oral allergy syndrome involving several fruits from 2 different families of the Rosidae subclass confirmed by in vitro tests. Inhibition studies demonstrated cross-reactivity between different fruits (currant and raspberry) from the Rosidae subclass and were incomplete with grass pollen allergens.
authors.affiliation: Allergy Department, Gregorio Marañón Hospital, Madrid, Spain. projasperezezquerra@hotmail.com
authors.forename: Patricia Rojas
authors.initials: PR
authors.lastname: Pérez-Ezquerra
authors.forename: Maria Vazquez Torre
authors.initials: MV
authors.lastname: de la Gaspar
authors.forename: Manuel Barrio
authors.initials: MB
authors.lastname: de Fernández
authors.forename: Vanesa Tovar
authors.initials: VT
authors.lastname: Flores
authors.forename: Ana Villanueva
authors.initials: AV
authors.lastname: Alvarez-Santullano
authors.forename: Maria Luisa Baeza Ochoa
authors.initials: ML
authors.lastname: de Ocáriz
mesh_terms: D003429:Cross Reactions; D005260:Female; D006801:Humans; D006967:Hypersensitivity / Q000209:etiology*; D007073:Immunoglobulin E / Q000097:blood; D008875:Middle Aged; D011058:Pollen / Q000276:immunology*; D031965:Ribes / Q000276:immunology*; D027824:Rosaceae / Q000276:immunology*; D012882:Skin Tests; D013577:Syndrome
chemical_list: D007073:Immunoglobulin E