An Increasing Trend of Eosinophilic Esophagitis in Korea and the Clinical Implication of the Biomarkers to Determine Disease Activity and Treatment Response in Eosinophilic Esophagitis.

BACKGROUND/AIMS: The epidemiology and pathogenesis of eosinophilic esophagitis (EoE) remain unclear in Asian countries. We investigated clinicopathological characteristics and diagnostic trends of EoE, and evaluated 3 tissue biomarkers for correlation with disease activity and treatment response in Korean patients with EoE.

METHODS

We retrospectively reviewed 25 271 esophageal biopsies performed during upper endoscopies between 2006 and 2017. We diagnosed EoE based on ≥ 15 eosinophils/high-power field (HPF) and, symptoms of esophageal dysfunction. We performed immunohistochemical analysis for tryptase, eosinophilic derived neurotoxin (EDN), and eotaxin-3.

RESULTS

We diagnosed EoE in 72 patients (53 men and 19 women; mean age, 46.2 years) with presenting symptoms of, dysphagia (15.3%), epigastric pain (31.9%), and heartburn (30.6%). The diagnostic rate of EoE considerably increased between 2006 and 2017, from 0.29 diagnoses to 7.99 diagnoses per 1000 esophageal biopsies ( P < 0.001). The mean peak eosinophil count (PEC) was 56.0 (± 77.8)/HPF. Whereas the EDN (rho = 0.667, P < 0.001) and eotaxin-3 levels (rho = 0.465, P < 0.001) correlated with PEC, tryptase and PEC were weakly correlated (rho = 0.291, P = 0.013). EDN (rho = 0.279, P = 0.017), and tryptase (rho = 0.279, P = 0.033) correlated with the inflammatory score of Eosinophilic Esophagitis Endoscopic Reference Score. Immunohistochemical analysis and changes in tryptase, EDN, and eotaxin-3 levels were associated with histologic and endoscopic improvements.

CONCLUSIONS

EoE incidence considerably increased during the 12-year period, regardless of endoscopic esophageal biopsy rate. Tryptase, EDN, and eotaxin-3 levels in esophageal biopsy specimens could be promising biomarkers for disease activity, symptom, and endoscopic response in Korea.