Who fails the egg ladder? Predictors of reactions and clinical outcomes with individualized entry-step selection in 197 children with IgE-mediated egg allergy.

Abstract

Egg ladders provide a structured approach to graded egg reintroduction in children with IgE-mediated egg allergy; however, identifying children at risk of reactions remains challenging, particularly because recent evidence has questioned the predictive value of baseline sensitization and previous anaphylaxis. Large real-world studies evaluating individualized egg ladder approaches remain limited. In this retrospective cohort study, we evaluated children with IgE-mediated egg allergy managed with a structured egg ladder at a tertiary pediatric allergy center over a 10-year period. Starting steps were selected individually according to clinical history and sensitization results; children considered unsuitable for direct initiation with baked whole egg could begin with baked egg yolk. The primary outcome was the occurrence of at least one protocol-related allergic reaction during ladder progression at the patient level; ladder completion was evaluated separately. Factors associated with reactions and noncompletion were assessed using logistic regression. Among 197 children, completion outcomes were available for 175, of whom 144 (82.3%) achieved whole egg tolerance after a median ladder duration of 13 months. Twenty-four children (12.2%) experienced at least one protocol-related allergic reaction, including anaphylaxis during supervised OFC in 12 (6.1%). Previous egg-induced anaphylaxis was independently associated with protocol-related reactions and noncompletion, whereas higher baseline egg white-specific IgE was associated with noncompletion only. In unadjusted analyses, initiation before 18 months was associated with fewer protocol-related reactions (3.4% vs 15.9%; p = 0.014), more frequent ladder completion (92.2% vs 78.2%; p = 0.028), and achievement of tolerance at a younger age (25.5 months vs 49.0 months, p < 0.001). However, age at initiation was not independently associated with reactions or noncompletion after adjustment.Conclusion: Previous egg-induced anaphylaxis identified children at increased risk of reactions and ladder noncompletion, while higher baseline egg white-specific IgE was associated with noncompletion. A baked egg yolk entry step was feasible in selected children considered unsuitable for direct baked whole egg initiation, although its comparative safety and clinical utility require prospective evaluation. The favorable unadjusted outcomes with initiation before 18 months were not confirmed after adjustment. What is Known: • Although egg ladders facilitate graded egg introduction in many children with IgE-mediated egg allergy, reliable identification of children at risk of reactions or ladder noncompletion remains challenging What is New: • Previous egg-induced anaphylaxis was independently associated with protocol-related reactions and ladder noncompletion, whereas higher baseline egg white-specific IgE was independently associated with noncompletion but not with reactions after adjustment. A baked egg yolk entry step was feasible in selected children, although its comparative safety could not be determined. Initiation before 18 months was associated with fewer reactions, more frequent completion, and achievement of tolerance at a younger age in unadjusted analyses, but age was not an independent predictor of these outcomes.