The diagnostic performance and accuracy of 3 molecular assays for the detection of Clostridium difficile in stool samples, compared with the Xpert® C. difficile assay

Abstract This research compares the performance and diagnostic accuracy of three molecular tests for the detection of Clostridium difficile in stool samples, with the Xpert® C. difficile assay. Fifty-nine positive and twenty-five stool negative samples were analyzed by the BDmax™ Cdiff, the Simplexa C. difficile Direct, and the GenomEra™ C. difficile, and compared with the Xpert® C. difficile routinely used in our laboratory. The highest sensitivity was 94.9% for the BDmax™ Cdiff, followed by GenomEra™ C. difficile with 93.2%, and Simplexa™ C. difficile Direct with 89.8%. The specificities of all assays were 100%. GenomEra™ C. difficile had the highest retesting rate (12%). Simplexa™ C. difficile Direct benefits from both short hands-on time and total-turnaround time and 0% retesting. The differences in performance and accuracy between these three molecular assays are insignificant and all may be used as part of the routine algorithm for detection of C. difficile.