The Food Allergy-Eosinophilic Esophagitis Continuum: Implications for Food Allergy Immunotherapy

IgE-mediated food allergy and eosinophilic esophagitis (EoE) represent distinct yet interconnected manifestations of food-induced immune dysregulation. Rather than separate entities, emerging evidence supports a model that is on a continuum, in which clinical phenotypes are determined by antigen exposure patterns, dose, chronicity, and individual immune responses. This relationship has critical implications for food allergy immunotherapy, particularly oral immunotherapy. Among children with IgE-mediated food allergy, EoE prevalence is nearly 100-fold higher than the general population at 4.7%. During oral immunotherapy, gastrointestinal symptoms are common, with confirmed EoE developing in 1% to 10% of participants. Mechanistically, antigen avoidance favors IgE-mediated responses through T follicular helper cells, whereas sustained exposure promotes T_H2-driven esophageal inflammation via pathogenic effector T_H2 cells. Regulatory T-cell dysfunction appears central to this phenotypic switching. Clinical management requires risk stratification, systematic monitoring strategies, and individualized protocols that balance desensitization benefits against esophageal inflammation risks. Future directions include noninvasive diagnostic biomarkers, biologic therapies, and evidence-based prevention strategies. Understanding the food allergy-EoE continuum is essential for optimizing safety and efficacy of food allergen immunotherapy while minimizing complications.