Screening for C. Difficile
A panel of clinicians recognize the challenges associated with screening patients for the C. difficile infection and highlight factors that should prompt someone for an evaluation.
Peter L. Salgo, MD: We’d like to know if somebody in the household is giving everybody else this disease. Or we’d like to know if somebody has the spores and is not sick but is at risk if we give them antibiotics. How common is it for someone to be an asymptomatic carrier? And whom do you test? Why do you test? Where are you with all this, Teena? You’ve got about 4 minutes. You’re off to the races.
Teena Chopra, MD, MPH: It’s a very complex issue, asymptomatic carriage. But it’s a very important one because these patients can act as reservoirs of transmission and probable vehicles of transmission to other patients. It’s very important that we realize that. For example, 18% to 20% of neonates can be asymptomatic carriers. Older adults can have an asymptomatic carrier rate of anywhere from 0% to 50%. Healthy adults, anywhere from 5% to 10%. It depends on different kinds of populations, but it’s important that we understand and we realize that because these asymptomatic carriers don’t have diarrhea, but we are detecting Clostridium diff in them. They don’t have the disease, but they are detecting C diff because they are reservoirs and they can easily transmit it to others. Hence the importance of infection control, particularly in the health care setting, alternate health care settings, outpatient clinics, or dialysis units. It is important to recognize the importance of hand hygiene and contact precautions for these patients.
Peter L. Salgo, MD: What I’m trying to understand is: Here’s a person with no diarrhea and no symptoms. You’re telling me there’s an aliquot of these folks who are asymptomatic carriers. Whom are you testing? Why are you testing these people if they’re asymptomatic? They come into your office and say, “It’s a Wednesday. It’s a good day to test. Let’s do it.” Or is there some reason you’re testing?
Teena Chopra, MD, MPH: Based on studies, it’s been done only as a research project or a quality-improvement project. But routinely, we don’t test for asymptomatic carriage in the hospital setting. Yes, we can understand that these patients could have risk factors for having asymptomatic carriers, and moving forward we want to put them in contact isolation so they don’t transmit infection. But routinely, very few hospitals do it unless they are facing outbreaks.
Peter L. Salgo, MD: If there’s an outbreak, then you’re trying to get everybody in the tent and test them. But short of that, you’re not advocating primary care doctors—as part of the screening protocol for everything out there—get asymptomatic testing for C diff, are you?
Teena Chopra, MD, MPH: No, not everybody should be tested. That would be a poor use of resources.
Peter L. Salgo, MD: It’s expensive.
Dale N. Gerding, MD: We struggled with this question in writing the guidelines in terms of whether you should screen patients on admission for carriage of C diff. Admitted patients to the hospital generally have a carriage rate of somewhere between 6% and sometimes as high as 12%, largely because they’ve been in the hospital before. But we didn’t feel there were sufficient data to recommend that strategy. It’s invasive. It also takes up a lot of your isolation rooms if you respond to positive patients by isolating them. We need more data before we jump on the colonization bandwagon, even in hospitals. In the community it’s a very low rate. In Western communities, the carriage rate when we’d done it in sample patients is more like 2%, possibly 3% at most.
Peter L. Salgo, MD: If you enjoyed this content, you should subscribe. We have an e-newsletter, and you can receive upcoming Peer Exchanges and other great content in your in-box—that’s right, electronically. I’ll see you next time. I’m Dr Peter Salgo. Thanks again for watching.
