title: Evaluation of the fully automated BD MAX Cdiff and Xpert C. difficile assays for direct detection of Clostridium difficile in stool specimens.
abstract: We evaluated the fully automated molecular BD MAX Cdiff assay (BD Diagnostics) and the Xpert C. difficile test (Cepheid) for rapid detection of Clostridium difficile infection. Culture was done on chromogenic agar followed by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry identification and toxin detection. Repeat testing was required for 1.8% and 6.0% of the BD MAX and Xpert tests, respectively. Sensitivities, specificities, positive predictive values (PPV), and negative predictive values (NPV) were 90.5%, 97.9%, 89.3%, and 98.1%, respectively, for BD MAX and 97.3%, 97.9%, 90.0%, and 99.5%, respectively, for Xpert.
authors.affiliation: Department of Infectious Diseases, Medical Microbiology and Hygiene, University Hospital Heidelberg, Heidelberg, Germany. alexander.dalpke@med.uni-heidelberg.de
authors.forename: Alexander H
authors.initials: AH
authors.lastname: Dalpke
authors.forename: Marjeta
authors.initials: M
authors.lastname: Hofko
authors.forename: Markus
authors.initials: M
authors.lastname: Zorn
authors.forename: Stefan
authors.initials: S
authors.lastname: Zimmermann
mesh_terms: D057205:Automation, Laboratory / Q000379:methods; D001427:Bacterial Toxins / Q000032:analysis; D001431:Bacteriological Techniques / Q000379:methods*; D002863:Chromogenic Compounds / Q000378:metabolism; D016360:Clostridioides difficile / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification*; D003015:Clostridium Infections / Q000175:diagnosis* / Q000382:microbiology*; D003470:Culture Media / Q000737:chemistry; D005243:Feces / Q000382:microbiology*; D006801:Humans; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods
chemical_list: D001427:Bacterial Toxins; D002863:Chromogenic Compounds; D003470:Culture Media