Eosinophilic esophagitis: current understanding and evolving concepts.

Eosinophilic esophagitis (EoE) is now considered to represent a form of food allergy and this is demonstrated by a response to elimination diet in many patients. A critical additional factor may be an inherent impairment in epithelial barrier integrity, possibly worsened by reflux of gastric contents and improved with proton pump inhibitor (PPI) use. Key clinic challenges are posed by the absence of reliable allergy tests to guide elimination diet, and the subsequent need for invasive endoscopic assessment following empirical food challenge, meaning that corticosteroids will remain the mainstay of therapy for many. From a research standpoint, determining if impairments in barrier integrity are innate, and how PPIs address this deficit (which may be pH independent) are important questions that when answered may allow future therapeutic advancement.