Pathomorphological features of eosinophilic esophagitis before and after treatment with proton pomp inhibitors

Eosinophilic esophagitis (EoE) is characterized by predominant eosinophilic infiltration of esophageal mucosa, >15 eosinophils in a high power field (HPF). Proton pomp inhibitors (PPI) are medications of choice to start therapy of EoE. OBJECTIVE: To perform histological and morphometric analysis of biopsy pieces of esophageal mucosa before and after treatment with PPI. MATERIAL AND METHODS: Of the 84 patients newly diagnosed with EoE, 30 were in the PPI therapy group. Patients underwent esophagogastroduodenoscopy with biopsy for initial diagnosis and follow-up evaluation. Biopsy specimens were stained with hematoxylin and eosin, combined PAS/Alcian blue staining and Mallory staining to detect fibrosis. Morphometric analysis was performed using the Eosinophilic Esophagitis Histologic Scoring System (EoEHSS) for initial diagnosis and Eosinophilic Esophagitis Histology Remission Score (EoEHRS) to assess the onset of remission. RESULTS: <0.05. CONCLUSION: Not only peak eosinophil count, but structural changes of esophageal mucosa should be taken into account while evaluating biopsies for initial diagnostic and to analyze the treatment response. EoEHRS remission criteria were reached in 40% patients on PPI therapy.