cobas® Cdiff Test

Answers that help stop the threat of infection

Molecular detection moves C. difficile testing forward


Traditional methods for identification of Clostridioides difficile (C.difficile) include toxigenic culture, which is labor intensive and slow, and enzyme immunoassays (EIA), which have limited sensitivity. Algorithms have been developed using combinations of EIA testing to overcome shortcomings of individual assays.1 However, these algorithms may introduce delays in reporting results to physicians, which adversely impacts patient management.

Molecular technologies (including nucleic acid amplification tests [NAAT]) offer better sensitivity and turnaround time in identifying toxigenic C. difficile when compared to several other approaches (glutamate dehydrogenase [GDH] assay, toxin A and B immunoassay, cell culture cytotoxicity neutralization assay), either alone or in combination.1

In recent years, the frequency and severity of C. difficile-associated disease has continued to increase, prompting a need for rapid and reliable C. difficile testing, particularly in vulnerable elderly populations. By rapidly detecting C. difficile in patient stool samples, the cobas Cdiff Test* on the cobas® 4800 System combines high assay sensitivity with rapid turnaround time and a minimum number of pre-analytic steps, to facilitate earlier intervention of patients suffering from C. difficile-associated disease.

Reduce hands-on time with the flexible, automated workflow

Accuracy delivered efficiently

The cobas® Cdiff Test requires only 3 simple steps for sample prep, minimizing sample handling.

Less hands-on time means more walk-away time

The cobas® Cdiff Test requires up to 70% less hands-on time than competitor platforms. 3

cobas cdiff test hands-on time
Run mixed batch assays

The cobas® 4800 System offers flexibility with parallel sample processing capabilities. cobas® Cdiff samples can be run with different tests and sample types in one run, including:

  • Stool (cobas® Cdiff Test)
  • Nasal (cobas® MRSA/SA Test)
  • Anogenital lesions (cobas® HSV 1 and 2 Test)
Intended use

The cobas® Cdiff Test on the cobas® 4800 System is an automated, qualitative in vitro diagnostic test, that utilizes real-time polymerase chain reaction (PCR), for the direct detection of the toxin B (tcdB) gene of toxigenic Clostridium difficile in unformed (liquid or soft) stool specimens obtained from patients suspected of having C. difficile infection (CDI). The cobas® Cdiff Test is intended for use as an aid in the diagnosis of CDI in humans in conjunction with clinical and epidemiological risk factors.

Registration status



  1. Surawicz et al. Guidelines for diagnosis, treatment, and prevention of Clostridium difficile infections. Am J Gastroenterol. 2013 Apr;108(4):478-98.
  2. cobas® Cdiff Test [package insert]. Indianapolis, IN: Roche Diagnostics; 2016.
  3. Argent Microbiology Workflow Study 2014. Roche data on file.