title: Influencing Factors to Results of the Urease Test: Age, Sampling Site, Histopathologic Findings, and Density of Helicobacter pylori.
abstract: OBJECTIVE
  We investigated the positivity rate and the time period to the positive color change of the urease test in children and adults and assessed the correlation of the urease test to histopathologic findings.
  
  
  METHODS
  From 1995 to 2000, endoscopic biopsies of the antrum and body were collected from 811 children and 224 adults and subjected to urease tests and histopathology.
  
  
  RESULTS
  The positivity rate of the urease test was 49.4% for 0-4 years, 48.4% for 5-9 years, 47.3% for 10-15 years, and 62.5% for 20-29 years in the antrum. The positivity rate was 85.1% in 0-4 years, 82.3% in 5-9 years, 74.7% in 10-15 years, and 74.1% in 20-29 years for the body. In the antrum, the highest positivity rate was <1 hour for the group aged 10-29 years and 6-24 hours in the group <10 years old (p<0.0001). In the body, the highest positivity rate was <1 hour in adults and 6-24 hours in children (p<0.0001). The proportions of the positive reactions within 1 hour were similar for the antrum and the body. In the cases of more severe chronic gastritis, active gastritis, and Helicobacter pylori infiltration, a positive urease test reaction occurred more quickly (p<0.0001).
  
  
  CONCLUSIONS
  There were significant differences in urease tests according to age and sampling site. The discrepancy between the antrum and the body was greater in younger children. These results might be related to the low density and patchy distribution of bacteria in children and in the body.
authors.affiliation: Department of Pediatrics, Institute of Health Sciences, School of Medicine, Gyeongsang National University, Jinju, Korea.
authors.forename: Ji-Hyun
authors.initials: JH
authors.lastname: Seo
authors.forename: Hee-Shang
authors.initials: HS
authors.lastname: Youn
authors.forename: Jung-Je
authors.initials: JJ
authors.lastname: Park
authors.forename: Jung Sook
authors.initials: JS
authors.lastname: Yeom
authors.forename: Ji Sook
authors.initials: JS
authors.lastname: Park
authors.forename: Jin-Su
authors.initials: JS
authors.lastname: Jun
authors.forename: Jae-Young
authors.initials: JY
authors.lastname: Lim
authors.forename: Chan-Hoo
authors.initials: CH
authors.lastname: Park
authors.forename: Hyang-Ok
authors.initials: HO
authors.lastname: Woo
authors.forename: Gyung-Hyuck
authors.initials: GH
authors.lastname: Ko
authors.forename: Seung-Chul
authors.initials: SC
authors.lastname: Baik
authors.forename: Woo-Kon
authors.initials: WK
authors.lastname: Lee
authors.forename: Myung-Je
authors.initials: MJ
authors.lastname: Cho
authors.forename: Kwang-Ho
authors.initials: KH
authors.lastname: Rhee
keywords: Age; Helicobacter pylori infection; Pathology; Urease test