Testing for C. difficile: What Are the Limitations?

Belinda Ostrowsky, MD, MPH, Health Systems Director of Epidemiology, Antimicrobial Stewardship & Infection Prevention, Montefiore Medical Center, and Associate Professor of Clinical Medicine, Division of Infectious Diseases, Department of Medicine, Albert Einstein College of Medicine, discusses limitations to C. difficile testing that could impact stewardship practices in healthcare facilities.

Interview Transcript (slightly modified for readability)

“One [limitation], we mentioned, [when] we were talking about the limitations of [Clostridium difficile] testing, is that depending on the method that you use, some of the toxin tests, which are the older tests, might not be so sensitive, and so, they may miss cases. Our PCR tests, which are very sensitive, may pick up patients who are not symptomatic with C. diff.

There is a session [Pro/Con: Is It Good to Know—Universal Surveillance for C. Difficile?] here at SHEA, [which discusses] the pros and cons for potentially screening patients as they come in [to the hospital], because we do know that colonized patients, if they get antibiotics, may ultimately develop symptomatic C. diff. But the jury is out [on] what to do with that.

At least for now, one of the limitations is that if you [are] over-testing patients, you may inadvertently pick up a person who [does] not really [have] C. diff; that may be bad for the patient [who] could be unnecessarily isolated, it may be bad that they may get unnecessary treatment, and, now that we report many of our hospital-acquired infections outside of our facility, it may be bad for your facility, because it may (especially if that patient has been in your facility for several days) count as a hospital onset case in your rates of C. diff.”