Unravelling the pathogenesis of Eosinophilic Esophagitis from genetic predisposition to environmental triggers.

Eosinophilic Esophagitis (EoE) is a chronic disease primarily driven by immune-mediated pathogenesis, characterized by eosinophil-driven inflammation of the oesophagus, leading to organ dysfunction and fibrosis. Although initially considered a rare disorder, EoE is now recognized as one of the leading causes of food impaction and dysphagia. Advances in knowledge and diagnostic techniques have contributed to its increased detection; however, epidemiologic data suggest that the surge in incidence represents an actual rise in disease prevalence rather than solely increased awareness. The pathogenesis of EoE remains largely unclear, but it is believed to involve a complex interplay of genetic predisposition, environmental factors, diet-derived allergens, and immune dysregulation. A significant role in the pathogenesis of EoE is attributed to environmental and, particularly, food allergens, with mechanisms that extend beyond IgE-mediated pathways, as evidenced by the lack of efficacy of anti-IgE therapies such as omalizumab in clinical trials. A key pathogenic feature is the dysregulated activation of pathways mediated by T-helper type 2 (Th2) lymphocytes. Supporting the role of the Th2 system in EoE inflammation is the demonstrated efficacy of monoclonal inhibitors of interleukin 4 and 13 (i.e. dupilumab), currently the only approved biological therapy for this condition. Additionally, the role of autophagic processes in EoE pathogenesis is becoming increasingly evident. This review aims to provide a concise overview of the key pathogenic mechanisms of EoE and the currently available diagnostic approaches, both invasive and non-invasive, for managing this disorder.