Component‐resolved diagnostics demonstrates that most peanut‐allergic individuals could potentially introduce tree nuts to their diet

Summary Background Nut allergy varies from pollen cross‐allergy, to primary severe allergy with life‐threatening symptoms. The screening of IgE antibodies to a wide spectrum of allergens, including species‐specific and cross‐reactive allergens, is made possible via microarray analysis. Objective We sought to study the association of variable IgE sensitization profiles to clinical response in peanut‐challenged children and adolescents in a birch‐endemic region. In addition, we studied the avoidance of tree nuts and species‐specific sensitizations. Methods We studied 102 peanut‐sensitized patients who underwent a double‐blind placebo‐controlled challenge to peanut. We analysed ISAC ImmunoCAP microarray to 112 allergens, singleplex ImmunoCAPs for hazelnut Cor a 14 and cashew Ana o 3, and performed skin prick tests to peanut, tree nuts and sesame seed. We surveyed avoidance diets with a questionnaire. Results Sensitization to PR‐10 proteins was frequent (Bet v 1 90%), but equally high in the challenge negatives and positives. IgE to Ara h 2 and Ara h 6 discriminated peanut allergic (n = 69) and tolerant (n = 33) the best. Avoidance of tree nuts was common (52% to 96%), but only 6% to 44% presented species‐specific sensitizations to tree nuts, so a great number could potentially introduce these species into their diet. Conclusions and clinical relevance PR‐10‐sensitizations were frequent and strong regardless of peanut allergy status. Component‐resolved diagnostics can be employed to demonstrate to patients that sensitization to seed storage proteins of tree nuts is uncommon. Several tree nuts could potentially be reintroduced to the diet.