Introduction
Cashew nuts (CN) are a common cause of food allergies worldwide1–3 , often triggering more severe reactions than other foods4 5. The prevalence of CN allergies is on the rise6, possibly due its increasing use in the Western World’s diet. In Europe, peanuts are the primary cause of anaphylaxis in children under 18 years old, with CN ranking first in Switzerland7,8. Even a small amount (less than one teaspoon) of CN or peanut can induce an allergic reaction8. Notably, in only about 9% of all tree nut allergies and 29% of peanut allergies natural tolerance occurs9 10. Therefore, it is imperative to explore strategies to enhance reaction threshold and minimize the risk of severe reactions11.
In recent years, oral immunotherapy (OIT) has emerged as a promising therapeutic option for children with food allergies supported by encouraging data12–15. In 2018, the European Academy of Allergy and Clinical Immunology (EAACI) officially recommended allergen immunotherapy for peanut, milk and egg allergies in children above 4 years old with persistent Immunoglobulin E (IgE)-mediated food allergies16. However, several studies have shown that OIT increases the likelihood of allergic reactions, mostly mild in nature, but severe reactions are possible 1217. While OIT for tree nuts lacks official endorsement, it is frequently employed, yet data on its efficacy and safety remain scarce. The NUT CRACKER (Nut Co-Reactivity—Acquiring Knowledge for Elimination Recommendations) study, a prospective cohort study involving 50 patients undergoing CN OIT, showed promising results with a high rate of desensitization and moderate incidence of adverse reactions18. Another real-life analysis of preschool children who underwent OIT for tree nuts, including CN, demonstrated a moderate rate of side effects (70.7%)19.
This retrospective single-center study aimed to evaluate the safety and feasibility of CN OIT, comparing it with peanut OIT. We also aimed to identify factors influencing side effects and treatment duration.