Epidemiology and Natural History of Eosinophilic Gastrointestinal Disorders: Insights Gained and Remaining Gaps.

Eosinophilic gastrointestinal disorders (EGIDs) are chronic, immune-mediated conditions characterized by eosinophil-predominant inflammation of the gastrointestinal tract, encompassing eosinophilic esophagitis (EoE) and non-EoE EGIDs (eosinophilic gastritis, gastroenteritis, enteritis, and colitis). Over the past 3 decades, their clinical recognition has increased substantially, driven by rising incidence and prevalence-particularly for EoE, which is no longer considered rare in Western countries. In contrast, non-EoE EGIDs remain uncommon and incompletely characterized. Data reveal significant geographic variation and evolving epidemiologic patterns in EGIDs, including rapidly increasing EoE rates in East Asia. Early-life environmental exposures, gene-environment interactions, and Westernization-associated factors may contribute to these trends. EoE is typically chronic and progressive, with diagnostic delay associated with fibrostenotic complications, thus highlighting the importance of early recognition and maintenance therapy. Although non-EoE EGIDs were historically considered episodic, emerging data indicate that persistent disease is common, especially in pediatric populations. Across the spectrum, atopic comorbidities are frequent, and psychological burden is substantial. Together, these findings highlight EGIDs as chronic, evolving disorders with increasing prevalence that require earlier recognition, and long-term monitoring and management. Coordinated research initiatives are needed to close major gaps in diagnostic tools and thresholds, natural history, and long-term care.