title: Double positivity to bee and wasp venom: improved diagnostic procedure by recombinant allergen-based IgE testing and basophil activation test including data about cross-reactive carbohydrate determinants.
abstract: BACKGROUND
  Specific IgE (sIgE) antibodies to both bee and wasp venom can be due to a sensitivity to both insect venoms or due to cross-reactive carbohydrate determinants (CCDs).
  
  
  OBJECTIVE
  Investigating whether a basophil activation test (BAT) with both venoms as well as with bromelain and horseradish peroxidase (HRP) or recombinant allergen-based IgE testing can improve the diagnostic procedure.
  
  
  METHODS
  Twenty-two Hymenoptera-venom allergic patients with sIgE antibodies to both bee and wasp venom were studied. sIgE antibodies to MUXF3 CCD, bromelain, HRP, rApi m 1, and rVes v 5 were determined, and a BAT (Flow2 CAST) with venom extracts, bromelain, and HRP was performed. Further recombinant allergen-based IgE testing was done by using an ELISA, if required. The reactivity of basophils was calculated from the insect venom concentration at half-maximum stimulation.
  
  
  RESULTS
  Double positivity/double negativity/single positivity to rApi m 1 and rVes v 5 was seen in 12/1/9 patients. Further recombinant allergen-based IgE testing in the last ones revealed positive results to the other venom in all cases except one. BAT was double positive/double negative/single positive in 6/2/14 patients. Four patients with negative results in sIgE antibodies to CCDs had positive results in BAT. BAT with bromelain/HRP showed a sensitivity of 50%/81% and a specificity of 91%/90%.
  
  
  CONCLUSIONS
  Component-resolved IgE testing elucidates the pattern of double positivity, showing a majority of true double sensitizations independent of CCD sensitization. BAT seems to add more information about the culprit insect even if the true clinical relevance of BAT is not completely determined because of ethical limitations on diagnostic sting challenges. BAT with HRP is a good method to determine sensitivity to CCDs.
authors.affiliation: Department of Dermatology and Allergy Biederstein, Technische Universität München, Munich, Germany. eberlein@lrz.tum.de
authors.forename: Bernadette
authors.initials: B
authors.lastname: Eberlein
authors.forename: Lilian
authors.initials: L
authors.lastname: Krischan
authors.forename: Ulf
authors.initials: U
authors.lastname: Darsow
authors.forename: Markus
authors.initials: M
authors.lastname: Ollert
authors.forename: Johannes
authors.initials: J
authors.lastname: Ring
mesh_terms: D000485:Allergens / Q000235:genetics / Q000276:immunology; D000818:Animals; D001491:Basophils / Q000276:immunology*; D001514:Bee Venoms / Q000235:genetics / Q000276:immunology; D002241:Carbohydrates / Q000276:immunology; D003429:Cross Reactions / Q000276:immunology; D005260:Female; D006801:Humans; D006927:Hymenoptera / Q000276:immunology; D006969:Hypersensitivity, Immediate / Q000175:diagnosis* / Q000209:etiology / Q000276:immunology; D007073:Immunoglobulin E / Q000097:blood*; D019476:Insect Proteins / Q000235:genetics / Q000276:immunology; D008297:Male; D010741:Phospholipases A / Q000235:genetics / Q000276:immunology; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D012680:Sensitivity and Specificity; D060149:Tetraspanin 30; D014862:Wasp Venoms / Q000235:genetics / Q000276:immunology
chemical_list: D000485:Allergens; D001514:Bee Venoms; C554586:CD63 protein, human; D002241:Carbohydrates; D019476:Insect Proteins; D011994:Recombinant Proteins; D060149:Tetraspanin 30; C431905:Ves v 5 allergen; D014862:Wasp Venoms; D007073:Immunoglobulin E; D010741:Phospholipases A; C497838:Api m 1 allergen, Apis mellifera