Anaphylaxis to Peanut in a Patient Predominantly Sensitized to Ara h 6

作者：Asarnoj A^*; Glaumann S; Elfstrom L; Lilja G; Lidholm J; Nilsson C; Wickman M

来源：International Archives of Allergy and Immunology, 2012, 159(2): 209-212.

DOI：10.1159/000336027

• Anaphylaxis
• Food allergy
• Peanut
• Ara h 2
• Ara h 6

Diagnosis of peanut allergy has improved thanks to component-resolved diagnostics. Peanut allergen component Ara h 2 is considered to indicate true peanut allergy. The component Ara h 6 is structurally similar to Ara h 2, but the diagnostic value of analyzing IgE antibodies to Ara h 6 is unclear. A boy sensitized (>= 0.35 kU(A)/I) to Ara h 8 but not to Ara h 1, Ara h 2 and Ara h 3 was challenged with peanut and developed grade II anaphylaxis. In serum collected at the time of challenge a doubling of IgE to the peanut allergen extract was observed compared to allergy testing 9 months earlier. In contrast, IgE levels to Ara h 1, Ara h 2, Ara h 3 and to Ara h 8 were rather unchanged. After another 2 months, Ara h 6 was analyzed and revealed a level of 24 kU(A)/I whilst Ara h 2 was 0.12 kU(A)/I. We suggest that IgE sensitization to Ara h 6 caused the reaction and conclude that analyses of IgE levels to peanut and peanut components should be performed in connection with a challenge. Furthermore, levels to Ara h 2 below 0.35 kU(A)/I may still indicate a risk of severe reaction at the time of challenge since in rare cases, Ara h 6 IgE antibodies may be present without occurrence of IgE antibodies to Ara h 2.

• 出版日期2012