Prevalence of Esophageal Eosinophilia and Eosinophilic Esophagitis in Adults: A Population-Based Endoscopic Study in Shanghai, China

Background and Aim Population-based endoscopic studies of esophageal eosinophilia and eosinophilic esophagitis are limited in the world. This study was aiming to describe features of esophageal eosinophilia and eosinophilic esophagitis in a representative sample of the adult in Shanghai, China. Methods As part of a large epidemiological study, 3,600 individuals (aged 18-80 years) were randomly selected in Shanghai, China. They were asked to undergo endoscopy and have at least four esophageal biopsies taken from 0.5 cm above the Z-line and any abnormal areas. Any eosinophil infiltration of the epithelium was defined as esophageal eosinophilia. Eosinophilic esophagitis was defined as >= 15 eosinophils/high-power field in esophageal biopsies. Results A total of 1,030 individuals accepted to have endoscopy and 1,021 individuals with biopsy results were suitable for analysis. Esophageal eosinophilia was present in 67 subjects (6.6 %). Eosinophilic esophagitis was present in four cases (0.4 %). No significant association was found between the presence of esophageal eosinophilia and reflux esophagitis, Barrett's esophagus, symptom-defined gastroesophageal reflux disease or H. pylori infection. Most individuals with esophageal eosinophilia (80.6 %) did not have any of the upper gastrointestinal symptoms. Conclusions Esophageal eosinophilia was present in nearly 6.6 % of the general adult population of China; 0.4 % had eosinophilic esophagitis. Most of individuals with esophageal eosinophilia were asymptomatic.