title: Diagnostic accuracy of three monoclonal stool tests in a large series of untreated Helicobacter pylori infected patients.
abstract: OBJECTIVE
  Immunochromatographic tests need to be improved in order to enhance their reliability. Recently, several new kits have appeared on the market. The objective was to evaluate the diagnostic accuracy of three monoclonal rapid stool tests - the new Uni-Gold™ H.pylori Antigen (Trinity Biotech, Ireland), the RAPID Hp StAR (Oxoid Ltd., UK) and the ImmunoCard STAT! HpSA (Meridian Diagnostics, USA) - for detecting H. pylori infection prior to eradication treatment.
  
  
  METHODS
  Diagnostic accuracy (sensitivity and specificity) and reliability (concordance between observers) were evaluated in 250 untreated consecutive dyspeptic patients. The gold standard for diagnosing H. pylori infection was defined as the concordance of two or more of rapid urease test (RUT), histopathology and urease breath test (UBT) or positive culture in isolation. Readings of immunochromatographic tests were performed by two different observers. Sensitivity, specificity, positive and negative predictive values and 95% confidence intervals were calculated. Sensitivity and specificity were compared using the McNemar test.
  
  
  RESULTS
  The three tests showed a good correlation, with Kappa values>0.9. RAPID Hp StAR had a sensitivity of 91%-92% and a specificity ranging from 77% to 85%. Its sensitivity was higher than that of Uni-Gold™ H.pylori Antigen and ImmunoCard STAT! HpSA (p<0.01). Uni-Gold™ H.pylori Antigen kit showed a sensitivity of 83%, similar to ImmunoCard STAT! HpSA. Specificity of Uni-Gold™ H.pylori Antigen approached 90% (87-89%) and was superior to that of RAPID Hp StAR (p<0.01).
  
  
  CONCLUSIONS
  Uni-Gold™ H.pylori Antigen and ImmunoCard STAT! HpSA present similar levels of diagnostic accuracy. RAPID Hp StAR was the most sensitive but less reliable of the three immunochromatographic stool tests. None are as accurate and reliable as UBT, RUT and histology.
authors.affiliation: Digestive Diseases Service, Hospital de Sabadell, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain; Fundació Parc Taulí, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain.
authors.forename: Sergio
authors.initials: S
authors.lastname: Lario
authors.affiliation: Digestive Diseases Service, Hospital de Sabadell, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: María José
authors.initials: MJ
authors.lastname: Ramírez-Lázaro
authors.affiliation: Digestive Diseases Service, Hospital de Sabadell, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Antònia
authors.initials: A
authors.lastname: Montserrat
authors.affiliation: Digestive Diseases Service, Hospital de Sabadell, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain; Fundació Parc Taulí, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain.
authors.forename: María Elisa
authors.initials: ME
authors.lastname: Quílez
authors.affiliation: Digestive Diseases Service, Hospital de Sabadell, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Félix
authors.initials: F
authors.lastname: Junquera
authors.affiliation: Digestive Diseases Service, Hospital de Sabadell, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Eva
authors.initials: E
authors.lastname: Martínez-Bauer
authors.affiliation: Microbiology Laboratory, UDIAT-CD, Hospital de Sabadell, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain; Spanish Network for Research in Infectious Diseases (REIPI RD06/0018), Spain.
authors.forename: Isabel
authors.initials: I
authors.lastname: Sanfeliu
authors.affiliation: Digestive Diseases Service, Hospital de Sabadell, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Enric
authors.initials: E
authors.lastname: Brullet
authors.affiliation: Digestive Diseases Service, Hospital de Sabadell, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Campo
authors.affiliation: Infectious Disease Service, Hospital de Sabadell, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain; Spanish Network for Research in Infectious Diseases (REIPI RD06/0018), Spain.
authors.forename: Ferran
authors.initials: F
authors.lastname: Segura
authors.affiliation: Digestive Diseases Service, Hospital de Sabadell, Corporació Sanitària Parc Taulí, Institut Universitari Parc Taulí-UAB, Sabadell, Spain; Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), Instituto de Salud Carlos III, Madrid, Spain. Electronic address: xcalvet@tauli.cat.
authors.forename: Xavier
authors.initials: X
authors.lastname: Calvet
mesh_terms: D000907:Antibodies, Bacterial / Q000276:immunology*; D000911:Antibodies, Monoclonal / Q000276:immunology*; D015415:Biomarkers / Q000032:analysis*; D005243:Feces / Q000737:chemistry* / Q000382:microbiology; D005260:Female; D005500:Follow-Up Studies; D016481:Helicobacter Infections / Q000175:diagnosis* / Q000382:microbiology; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D007159:Immunologic Tests / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D015203:Reproducibility of Results; D014510:Urease / Q000276:immunology / Q000378:metabolism
chemical_list: D000907:Antibodies, Bacterial; D000911:Antibodies, Monoclonal; D015415:Biomarkers; D014510:Urease
keywords: Dyspepsia; Feces; Helicobacter pylori; Immunochromatography; Sensitivity and specificity