A biscotti-based milk and egg ladder using stepwise oral food challenges: A retrospective study in high-risk children

Background: Cow's milk and hen's egg allergy are the most common immunoglobulin E (IgE) mediated food allergies in childhood. Current oral immunotherapy protocols use the native raw allergen, with severe anaphylaxis reported. Objective: The objective was to retrospectively evaluate the safety and clinical outcomes of a biscotti (twice baked cake) based milk and egg ladder by using stepwise oral food challenges in children at high risk. Methods: In this single-center retrospective review (June 2024 to April 2025), records of 33 children with IgE-mediated cow's milk protein allergy (n = 11) or hen's egg allergy (n = 22) were reviewed. The milk ladder comprised seven steps over 12 weeks and progressed from 3-, 2-, and 1-hour second-bake biscotti to a single-bake cake, tempered yogurt soup, yogurt, and pasteurized milk. Yogurt, rather than liquid milk, served as the dairy matrix until the final pasteurized-milk step. The egg ladder comprised six steps with an analogous structure ending at boiled egg. At each step, a five-step in-hospital oral food challenge was performed on the first day. Results: The median age was 19.0 months (milk) and 14.0 months (egg). The median baseline specific IgE levels to milk and egg were 49.7 kUA/L and 19.85 kUA/L, respectively. All adverse reactions were mild. Gastrointestinal reactions clustered in the first three biscotti steps, whereas cutaneous reactions were concentrated in later steps. No reactions were observed at the cake or soup steps, and no anaphylaxis or epinephrine requirement occurred. At the end, 33 of 33 patients tolerated pasteurized milk or boiled egg. Conclusion: This biscotti-based milk and egg ladder, structured according to cooking duration, was implemented with a mild adverse-reaction profile and achieved clinical desensitization in all 33 patients. Adaptation of the biscotti approach to egg allergy and the use of yogurt as the dairy matrix in place of liquid milk are original design contributions; findings are hypothesis-generating and warrant randomized controlled prospective validation.