Eosinophilic Esophagitis

Eosinophilic Esophagitis is a chronic allergic/immune-mediated inflammatory disease of the esophagus characterized by eosinophil-predominant infiltration of esophageal mucosa and submucosa. The pathophysiology involves T helper 2 (Th2)-mediated immune response to food and/or environmental antigens, with characteristic eosinophil recruitment and degranulation. Histologic diagnosis requires 15 or more eosinophils per high-powered field on esophageal biopsy and exclusion of other conditions causing esophageal eosinophilia. The chronic inflammation leads to esophageal remodeling with stricture formation, progressive narrowing, and dysmotility. Patients present with dysphagia and food impaction, sometimes dramatically with acute impaction episodes requiring endoscopic intervention. Chest pain can occur. Children may have subtle symptoms including failure to thrive or vomiting, whereas adults typically present with dysphagia and impaction episodes. Progressive stricturing develops with repeated cycles of inflammation and healing. The disease is associated with atopic conditions and IgE-mediated food allergy in many patients, though half have no identified food triggers. Recently, proton pump inhibitor (PPI)-responsive esophageal eosinophilia (PPIE) was recognized as a potentially distinct phenotype.