title: Prevalence of esophageal eosinophilia and eosinophilic esophagitis in adults: a population-based endoscopic study in Shanghai, China.
abstract: OBJECTIVE
  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.
authors.affiliation: Department of Health Statistics, Second Military Medical University, Shanghai, 200433, China, horse_ma88@yeah.net.
authors.forename: Xiuqiang
authors.initials: X
authors.lastname: Ma
authors.forename: Qin
authors.initials: Q
authors.lastname: Xu
authors.forename: Yanling
authors.initials: Y
authors.lastname: Zheng
authors.forename: Yanfang
authors.initials: Y
authors.lastname: Zhao
authors.forename: Jian
authors.initials: J
authors.lastname: Lu
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.forename: Zhaoshen
authors.initials: Z
authors.lastname: Li
authors.forename: Duowu
authors.initials: D
authors.lastname: Zou
authors.forename: Jia
authors.initials: J
authors.lastname: He
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001706:Biopsy; D002681:China / Q000453:epidemiology; D057765:Eosinophilic Esophagitis / Q000453:epidemiology*; D004945:Esophagoscopy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011795:Surveys and Questionnaires