title: Predictive value of the sulfidoleukotriene release assay in oral allergy syndrome to celery, hazelnut, and carrot.
abstract: BACKGROUND
  Patients sensitized to birch pollen frequently suffer from a food allergy to plant foods such as celery, carrots, or hazelnut. One of the main manifestations of birch pollen-related food allergy is the oral allergy syndrome. Skin tests and allergen-specific immunoglobulin (Ig) E determinations are poor predictors of such reactions when assessed by double-blind placebo-controlled food challenge (DBPCFC).
  
  
  OBJECTIVE
  To investigate whether a cellular test based on leukotriene release from basophils, the cellular antigen stimulation test in combination with enzyme-linked immunosorbent assay (CAST-ELISA), is predictive of pollen-related food allergy.
  
  
  METHODS
  Birch pollen-sensitized patients with positive DBPCFC to celery (n=21), hazelnut (n=15), and carrot (n=7) underwent skin tests along with determination of specific IgE and CAST-ELISA for the respective allergens. The results were compared with those of 24 birch pollen-sensitized patients with negative open food challenge to celery, hazelnut, and carrot.
  
  
  RESULTS
  While skin prick tests had a sensitivity of 85%, 80%, and 29% for commercial extracts of celery, hazelnut, and carrot, respectively, prick testing with self-prepared extracts yielded sensitivities of 100%, 80%, and 100%, respectively. For specific IgE determinations, sensitivities were 71%, 73%, and 57%, respectively, and the respective specificities were 67%, 73%, and 60%. For CAST-ELISA with various sources and doses of allergens, the sensitivity varied from 71% to 95% for celery, 73% to 80% for hazelnut, and 43% to 86% for carrot. The respective specificities were 67% to 92%, 75% to 88%, and 77% to 91%. Analysis of the predictive value of CAST-ELISA with receiver operating characteristic curves showed that the results of the tests were more predictive of pollen-related food allergy than quantitative allergen-specific IgE determinations.
  
  
  CONCLUSIONS
  CAST-ELISA is more specific than routine diagnostic tests for the diagnosis of pollen-related food allergy to celery, hazelnut, and carrot.
authors.affiliation: Allergy Unit, Department of Dermatology, University of Zurich, Switzerland. barbara.ballmer@usz.ch
authors.forename: B K
authors.initials: BK
authors.lastname: Ballmer-Weber
authors.forename: J M
authors.initials: JM
authors.lastname: Weber
authors.forename: S
authors.initials: S
authors.lastname: Vieths
authors.forename: B
authors.initials: B
authors.lastname: Wüthrich
mesh_terms: D000293:Adolescent; D000328:Adult; D000077102:Apium / Q000276:immunology*; D001491:Basophils / Q000166:cytology / Q000378:metabolism; D029662:Betula; D031211:Corylus / Q000276:immunology*; D018552:Daucus carota / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D005512:Food Hypersensitivity / Q000097:blood / Q000150:complications / Q000175:diagnosis* / Q000276:immunology; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D015289:Leukotrienes / Q000032:analysis* / Q000276:immunology / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D006255:Rhinitis, Allergic, Seasonal / Q000150:complications / Q000276:immunology; D012882:Skin Tests
chemical_list: D015289:Leukotrienes; D007073:Immunoglobulin E