Re-Introducing Nuts in Allergic Patients

Inclusion Criteria: * Written informed consent from adult participants or parent/guardian for children. Written assent from participants above the age of 12 years. * Male or female participants aged 5 through 40 years, in a good general health condition according to the participant's medical history and the clinical examination and no chronic diseases, except: * Allergic rhinitis * Asthma controlled with therapy steps 1-3 according to Global Initiative for Asthma (GINA) 2017. * Well-controlled atopic dermatitis. * SPT to tree nut's extract and/or the natural tree nut (Prick-to-Prick) ≥ 3 mm (the largest diameter of the wheal) and serum IgE to tree nut of ≥ 0.35 kUA/L. * sIgE \> 0.1 kUA/L to at least one seed storage protein of the offending tree nut, except for pistachio, where Ana o 3 will serve as a sensitization marker. * Positive baseline OFC, at any dose but the final, conducted following PRACTALL (Practical Issues in Allergology, Joint United States/European Union Initiative) / iFAAM (Integrated Approaches to Food Allergen and Allergy Risk Management) guidelines. * Exclusion of active co-allergy to walnut, almond or pistachio, unless they are introduced to the diet simultaneously, by a negative open OFC or a recent (within the last two months) history of uneventful digestion, except for pistachio introduction in participants who are co-allergic to cashew. * Forced Expiratory Volume at 1 second (FEV1) or Peak Expiratory Flow Rate (PEFR) ≥ 80% of predictive. * The…