Purpose of review: To present the clinical, endoscopic, and histologic features of eosinophilic esophagitis (EoE), review the current diagnostic guidelines for EoE, and present an approach for diagnosis of EoE. It will also highlight selected techniques that are under development that may be useful in the future for diagnosis of EoE.
Recent findings: Recently updated guidelines emphasize that EoE is a clinicopathologic condition. Specifically, three criteria must be met to diagnose EoE: clinical symptoms of esophageal dysfunction; an esophageal biopsy with a maximum eosinophil count of at least 15 eosinophils per high-power microscopy field, with few exceptions; and exclusion of other possible causes of esophageal eosinophilia, including proton-pump inhibitor responsive esophageal eosinophilia (PPI-REE). A PPI trial is typically required both to assess for PPI-REE and to evaluate for the presence of concomitant gastroesophageal reflux disease.
Summary: EoE is a chronic, immune-mediated disorder. Because no single symptom, endoscopic finding, or histopathologic feature is pathognomonic, diagnosis can be challenging. In the future, symptom scores, tissue or serum biomarkers, and genetic testing may play a role in diagnosis, but these methods have yet to be validated and are not yet recommended for routine clinical use.