title: Prospective evaluation of a new stool antigen test for the detection of Helicobacter pylori, in comparison with histology, rapid urease test, (13)C-urea breath test, and serology.
abstract: OBJECTIVE
  This study aimed to evaluate the efficacy of a new polyclonal enzyme immunoassay for the detection of Helicobacter pylori (H. pylori) antigen in stool by determination of the optimal cut-off value in the screening population.
  
  
  METHODS
  A consecutive 515 patients undergoing a routine health check-up were prospectively enrolled. H. pylori infection was defined if at least two of four tests (histology, rapid urease test, (13)C-urea breath test, and serology) were positive. A stool antigen test (EZ-STEP H. pylori) was performed for the detection of H. pylori. The optimal cut-off value was determined by the receiver-operator characteristic curve. The diagnostic performance of each test was evaluated with regard to the histological diagnosis of atrophic gastritis (AG)/intestinal metaplasia (IM), degree of AG/IM, and old age.
  
  
  RESULTS
  Sensitivity, specificity, positive and negative predictive values, and accuracy of the stool antigen test were 93.1%, 94.6%, 95.1%, 92.3%, and 93.8%, respectively. The sensitivity of histology, rapid urease test, and the (13)C-urea breath test ranged from 89.1% to 97.6%, and their specificity was > 98%, while serology had high sensitivity, but low specificity. The accuracy of the stool antigen test was comparable to that of other methods (93.6-95.9%), whereas it was higher than that of serology. The stool antigen test still showed good diagnostic performance in the setting of progression of AG/IM and in patients over 40 years.
  
  
  CONCLUSIONS
  The performance of a new stool antigen test was comparable to that of other methods in the diagnosis of H. pylori infection for the screening population, even with the presence of AG/IM.
authors.affiliation: Department of Internal Medicine and Healthcare Research Institute, Seoul National University Hospital Healthcare System Gangnam Center, Seoul, South Korea.
authors.forename: Jeongmin
authors.initials: J
authors.lastname: Choi
authors.forename: Chung Hyeon
authors.initials: CH
authors.lastname: Kim
authors.forename: Donghee
authors.initials: D
authors.lastname: Kim
authors.forename: Su Jin
authors.initials: SJ
authors.lastname: Chung
authors.forename: Ji Hyun
authors.initials: JH
authors.lastname: Song
authors.forename: Jung Mook
authors.initials: JM
authors.lastname: Kang
authors.forename: Jong In
authors.initials: JI
authors.lastname: Yang
authors.forename: Min Jung
authors.initials: MJ
authors.lastname: Park
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Kim
authors.forename: Jeong Yoon
authors.initials: JY
authors.lastname: Yim
authors.forename: Seon Hee
authors.initials: SH
authors.lastname: Lim
authors.forename: Joo Sung
authors.initials: JS
authors.lastname: Kim
authors.forename: Hyun Chae
authors.initials: HC
authors.lastname: Jung
authors.forename: In Sung
authors.initials: IS
authors.lastname: Song
mesh_terms: D000328:Adult; D000367:Age Factors; D000907:Antibodies, Bacterial / Q000097:blood; D000942:Antigens, Bacterial / Q000302:isolation & purification*; D001706:Biopsy; D001944:Breath Tests; D005243:Feces / Q000382:microbiology*; D005260:Female; D005757:Gastritis, Atrophic / Q000175:diagnosis / Q000382:microbiology / Q000473:pathology; D005773:Gastroscopy; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000382:microbiology / Q000473:pathology; D016480:Helicobacter pylori / Q000201:enzymology / Q000276:immunology*; D006801:Humans; D007124:Immunoenzyme Techniques; D008297:Male; D008679:Metaplasia; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D015203:Reproducibility of Results; D056910:Republic of Korea; D012698:Serologic Tests; D012720:Severity of Illness Index; D013270:Stomach / Q000382:microbiology* / Q000473:pathology; D014510:Urease / Q000378:metabolism*
chemical_list: D000907:Antibodies, Bacterial; D000942:Antigens, Bacterial; D014510:Urease