title: Novel portable platform for molecular detection of toxigenic Clostridium difficile in faeces: a diagnostic accuracy study.
abstract: BACKGROUND
  A novel portable platform for nucleic acid amplification enables rapid detection of diarrhoea causing toxigenic Clostridium difficile directly from faeces, even in resource-limited settings. We evaluated the accuracy and precision of the new commercial molecular test system.
  
  
  METHODS
  One thousand one hundred and sixty faecal samples from patients suspected of having Clostridium difficile infection (CDI) were analysed using the Orion GenRead C. difficile test system (Orion Diagnostica Oy, Espoo, Finland) and comparative methods in three teaching hospital laboratories in Finland and France. The precision of the Orion GenRead C. difficile test system was evaluated in a reproducibility study with a set of blind-coded samples. The test system is based on a new isothermal amplification technology (Strand Invasion Based Amplification, SIBA®) and detection of the tcdB gene of C. difficile. We calculated the sensitivity, specificity, and the overall agreement according to Clinical and Laboratory Standards Institute recommendations.
  
  
  RESULTS
  The overall agreement of the Orion GenRead C. difficile test when compared to the comparative methods in routine use in the participating laboratories was between 96.7% and 98.8%. In the reproducibility study; the total percent agreement between three laboratories was 99.8%.
  
  
  CONCLUSIONS
  The identification of toxigenic C. difficile from faeces with the light-weight portable Orion GenRead test system was highly sensitive and specific, and the results were reproducible in the participating laboratories. This platform could enable fast and accurate molecular pathogen detection even in resource-limited or point-of-care settings.
authors.affiliation: Fimlab Laboratories, P.O. Box 66, 33101, Tampere, Finland. jari.hirvonen@fimlab.fi.
authors.forename: J J
authors.initials: JJ
authors.lastname: Hirvonen
authors.affiliation: Department of Bacteriology and Immunology, University of Helsinki, P.O. Box 21, 00014, Helsinki, Finland. pirjo.matero@gmail.com.
authors.forename: P
authors.initials: P
authors.lastname: Matero
authors.affiliation: Laboratoire de Bactériologie, Grenoble University Hospital Centre, CHU de Grenoble CS 10217, 38 043, Grenoble Cedex, France.
authors.forename: C
authors.initials: C
authors.lastname: Siebert
authors.affiliation: NordLab Oulu, Kiviharjuntie 11, 90220, Oulu, Finland.
authors.forename: J
authors.initials: J
authors.lastname: Kauppila
authors.affiliation: Fimlab Laboratories, P.O. Box 66, 33101, Tampere, Finland.
authors.forename: R
authors.initials: R
authors.lastname: Vuento
authors.affiliation: NordLab Oulu, Kiviharjuntie 11, 90220, Oulu, Finland.
authors.forename: H
authors.initials: H
authors.lastname: Tuokko
authors.affiliation: Laboratoire de Bactériologie, Grenoble University Hospital Centre, CHU de Grenoble CS 10217, 38 043, Grenoble Cedex, France.
authors.forename: S
authors.initials: S
authors.lastname: Boisset
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics; D001427:Bacterial Toxins / Q000235:genetics; D016360:Clostridioides difficile / Q000235:genetics / Q000302:isolation & purification*; D003015:Clostridium Infections / Q000175:diagnosis* / Q000382:microbiology; D003967:Diarrhea / Q000175:diagnosis* / Q000382:microbiology; D005243:Feces / Q000382:microbiology*; D005387:Finland; D005602:France; D006784:Hospitals, Teaching; D006801:Humans; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D021141:Nucleic Acid Amplification Techniques / Q000379:methods; D019095:Point-of-Care Systems; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D001426:Bacterial Proteins; D001427:Bacterial Toxins; C031815:toxB protein, Clostridium difficile