What do the guidelines say?
To properly determine if a patient truly has CDI, a two-step algorithm testing approach includes:
1) a sensitive screening test
2) a specific toxin test
The American College of Gastroenterology (ACG)5 and the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA)6 guidelines recommend a multistep algorithm comprised of these steps.
The C. DIFF QUIK CHEK COMPLETE® test is a complete stand-alone 2-step C. difficile algorithm in one test.
The C. DIFF QUIK CHEK COMPLETE® test simultaneously provides both the screening and toxin results of a two-step algorithm in a single test. It improves workflow, speeds turnaround time, and offers significant cost savings over a PCR-first algorithm.
Why should I use a C. difficile multi-step testing algorithm?
C. difficile infection (CDI) is a toxin-mediated disease. Toxigenic strains of C. difficile can produce toxins A and B. While molecular testing methods such as polymerase chain reaction (PCR) and nucleic acid amplification tests (NAAT) can determine whether a C. difficile strain is capable of producing toxin (i.e. carries the toxin genes), these methods cannot determine whether the toxin is actively produced in the patient’s gut. Toxin gene expression does not happen in about half of cases.7 Toxin causes the disease. Without toxin production, the patient’s symptoms are likely due to another cause, and treating these colonized carriers for CDI may have adverse effects (i.e. increased antibiotic resistance and unnecessary isolation) as well as failure to clear the carriage.8-11
What about my “pre-agreed institutional criteria” for stool testing? That’s the first step in my algorithm, right?
While the 2021 ACG guidelines do not recommend NAAT-only testing for CDI, the 2018 IDSA/SHEA Guidelines do allow it with pre-agreed institutional sample criteria (i.e. ≥ 3 loose or unformed stools in ≤ 24 hours with history of antibiotic exposure). However, the pre-agreed institutional criteria is not part of the testing algorithm and the positive predictive value (PPV) of this approach is lower than that of a two-step algorithm.5
The C. DIFF QUIK CHEK COMPLETE® test is an efficient and clinically relevant testing solution.
Rapid clinical decisions are required for proper treatment of CDI patients, so it is critical to have quick and reliable results for both screening and toxin testing. With both GDH and toxin results in approximately 30 minutes, the C. DIFF QUIK CHEK COMPLETE® test differentiates active infection from colonization in a single cost-effective, clinically relevant test.