Test code 2817
Among the top 5 causes of serious food allergic reactions.1 Determine which of these proteins your patient has high levels of IgE to:
LOWER RISK of systemic reaction primarily associated with local reactions2
VARIABLE RISK associated with local and systemic reactions including anaphylaxis2,6,7
HIGHER RISK of systemic reaction including anaphylaxis2,4,9,10
Risk assessment and test interpretations
If antibodies are + for Cor a14 and/or Cor a9
- Associated with systemic reactions in hazelnut-sensitized patients2,4,9,10
- Test for sensitization to peanuts and other tree nuts (e.g., walnuts and Brazil nuts), as crossreactivity may occur11,12
If also positive for Cor a8, avoid raw as well as roasted/heated hazelnuts8
If antibodies are + for Cor a8
- Both local oral symptoms and systemic reactions may occur2,7
If also + for Cor a14 or Cor a9, avoid raw as well as roasted/heated hazelnuts8
If antibodies are + for Cor a1
- Typically associated with local reactions although systemic reactions to raw hazelnuts may occur in some cases, especially in adults2
- Often tolerate roasted or heated hazelnuts8
As in all diagnostic testing, a diagnosis must be made by the physician based on test results, individual patient history, the physician’s knowledge of the patient, and the physician’s clinical judgement.
1. Flinterman AE, et al. Hazelnut allergy: from pollen-associated mild allergy to severe anaphylactic reactions. Curr Opin Allergy Clin Immunol. 2008 Jun; 8(3): 261-265.
2. De Knop KJ, et al. Age-related sensitization profiles for hazelnut (Corylus avellana) in a birch-endemic region. Pediatr Allergy Immunol. 2011 Feb; 22(1Pt 2): e139–49.
3. Hansen KS, et al. Roasted hazelnuts-allergenic activity evaluated by double-blind, placebo-controlled food challenge. Allergy. 2003 Feb; 58(2): 132-138.
4. Masthoff L, et al. Sensitization to Cor a 9 and Cor a 14 is highly specific for a hazelnut allergy in Dutch children and adults. J Allergy Clin Immunol. 2013 Aug; 132(2):393-9.
5. Pastorello EA, et al. Identification of hazelnut major allergens in sensitive patients with positive double-blind, placebo-controlled food challenge results. J Allergy Clin Immunol. 2002; 109(3): 563-570.
6. Lauer I, et al. The non-specific lipid transfer protein, Ara h 9, is an important allergen in peanut. Clinical & Experimental Allergy. 39: 1427–1437.
7. Schocker F, et al. Recombinant lipid transfer protein Cor a 8 from hazelnut: A new tool for in vitro diagnosis of potentially severe hazelnut allergy. J Allergy Clin Immunol. 2004;113:141-7.
8. Masthoff L, et al. A systematic review of the effect of thermal processing on the allergenicity of tree nuts. Allergy. 2013; 68: 983–993.
9. Hansen KS, et al. Component-resolved in vitro diagnosis of hazelnut allergy in Europe. J Allergy Clin Immunol. 2009 Apr 1; 123(5): 1134-1141.
10. Garino C, et al. Isolation, cloning, and characterization of the 2S albumin: A new allergen from hazelnut. Mol Nutr Food Res. 2010; 54: 1257–1265.
11. Asero R, et al. Walnut-induced anaphylaxis with cross-reactivity to hazelnut and Brazil nut. J Allergy Clin Immunol. 2004 Feb; 113(2): 358-360.
12. Verweij M, et al. Young infants with atopic dermatitis can display sensitization to Cor a 9, an 11S legumin-like seed-storage protein from hazelnut (Corylus avellana). Pediatric Allergy Immnol. 2011; 22: 196-201.