Advancing the understanding of eosinophilic esophagitis: From pathogenesis to novel therapies

Eosinophilic esophagitis (EoE) is a chronic immune-mediated disease characterized by inflammation in the esophagus, occurring in genetically predisposed individuals as a consequence of food antigen sensitization. EoE prevalence has increased exponentially in the last three decades to 40 per 100000 people worldwide, making it a common cause of dysphagia and food impaction in both children and adults. Diagnosis is made by esophageal biopsy showing eosinophilia (≥ 15 eosinophils per high-power field on biopsy). In children the presentation may be feeding intolerance, in adults a form of chronic solid food dysphagia. In EoE, in the absence of treatment, active inflammation inevitably progresses to fibrostenotic remodeling, highlighting the importance of early recognition and therapy. This review outlines the clinical criteria and pathophysiological mechanisms of EoE, biomarkers for the diagnosis of EoE, and the therapeutic strategies for EoE. EoE is characterized by epithelial barrier dysfunction, Th2 inflammation and eosinophil recruitment, with microbiome influences. Diagnosis is made by standard endoscopic biopsy, or by non-intrusive esophageal string test, Cytosponge, or by impedance planimetry. Treatment includes proton pump inhibitors, topical corticosteroids, dietary elimination therapy, endoscopic dilation, and the Food and Drug Administration approved biologic dupilumab. Emerging therapies such as precision medicine and artificial intelligence are also identified as areas for attention.