As we make improvements in our infection control practices, both antimicrobial and diagnostic stewardship become even more important.”
— Larry Kociolek, MD, MSCI, FSHEA,
FPIDS our infection control practices, both antimicrobial and diagnostic stewardship become even more important. Patients will come into the hospital colonized with C. diff, oftentimes unrecognized and then we give them antibiotics that impact their microbiome that can result in that loss of colonization resistance, C. diff overgrowth and development of infection. So, it’ s important that all hospitals have an antimicrobial stewardship program and they ensure that antibiotics are used appropriately, for both the treatment of C. diff as well as other types of infections. We also know that focusing on higher-risk antibiotics like ceftriaxone, ciprofloxacin, clindamycin and carbapenems will have a greater impact of reducing C. diff infection.”
Before concluding his presentation, Kociolek also acknowledged there were issues that the multi-society Compendium committee was not able to resolve because of inconsistent data, or data that were not particularly strong, or interventions where the data might be somewhat compelling but the cost and operational challenges of implementation make it difficult to recommend as an essential strategy or an additional approach.“ Whether or not we should test C. diff carriers and put them into contact precautions has not been clearly shown to prevent transmission in all cases,” he said.“ There are some limited data to support that but not enough to make this a wholehearted recommendation. Touchless disinfection technologies such as vaporized hydrogen peroxide and UV disinfection, in some single-center small studies have shown promise; in the largest RCT on that, there was not a convincing drop in C. diff. Regarding probiotics, if you give enough patients probiotics, there’ s a very modest reduction, but it is so modest that you have to treat thousands of patients to see a statistical significance. There are also a lot of challenges related to quality control of the probiotic dose, how it’ s manufactured, etc. and so it’ s still unresolved as to whether or not this should be fully recommended.”
During the town hall event’ s Q & A session, the panelists fielded queries from attendees. One of the most requested topics for the panelists to address was that of the NHSN’ s definition of CDI. Shenoy tossed this topic to Kociolek, who explained,“ So, moving from hospital onset to hospital-treated CDI-- for any infection, you need to have a clear, reproducible definition and there are two ways to do that. You can use the lab alerts where if you are positive for C. diff and a test, it’ s reported as an infection. And if you’ ve been in the hospital for four days or more, it’ s reported as a healthcare-associated infection, a hospital-onset C. diff infection. That’ s the most common and most convenient way to perform that surveillance. We know there are two ways to test for C. diff; one method is with a nucleic acid amplification test, which is highly sensitive and oftentimes can over-diagnose C. diff by misidentifying colonized patients as infected. The other method is using a toxin-based test, which is highly specific for clinical C. diff but may lack sensitivity; with the differences in that testing’ s predictive value, the NHSN has said if your classification is based on the last test that you do, and so many hospitals will do a PCR first or a nucleic acid amplification test, first follow up with the toxin and if the toxin’ s negative, it’ s not considered to be an infection. But if you had done the toxin test first and that’ s negative and the PCR is positive, then that would be counted as an HAI. Some hospitals have gamed the system by doing the toxin test last. The issue is that would be perfectly acceptable if we didn’ t treat those patients who got the toxin that were toxin negative, but we know 75 to 80 percent of patients who are toxin-negative and PCR-positive will end up receiving treatment. CDC has proposed a new definition called hospital-onset treated C. diff infection, meaning if you otherwise are positive for C. diff and have been in the hospital for four days and you receive treatment for C. diff, then that will even the playing field. I haven’ t heard of any recent updates; I know the CDC is looking to collect these data,
validate them, and potentially roll this out in a phased approach, but there has been no announcement yet as to whether that will be formally adopted.”
The panel then turned to the topic of the benchmark change from 2015 to 2022 and how to achieve lower SIRs. Marci Drees, MD, MS, DTMH, FACP, FSHEA, of Christiana Care, mphasized,“ I think it’ s important to realize that your SIRS that you are looking at every month or every quarter are not contemporaneous, they are based on old data. So, since 2015, everyone has improved. When you start to run your new 2022 benchmark for almost every HAI, I would expect your SIRS to go up because we’ ve gotten better, and I think now that they’ re available, even though they’ re not being used publicly at all yet, what we’ ve started to do is normalize them internally so that we present the 2015 and 2022 data side by side and show that‘ Hey, it’ s the same number of infections, or it’ s the expected number of infections or infections have gone down, making the SIR go up’ and we’ re just starting to get people to start to think about it. We knew for a long time that the NHSN one criteria was too high for us, so we also internally benchmarked to the CMS mean, or to the Vizient mean or whatever sources of data you have; this is helpful that way people such as your hospital leaders who are paying for your program aren’ t going to be taken by surprise when the 2022 benchmark becomes official.”
Panelists next turned to the topic of current testing strategies.
“ We used to use just a single-step PCR test for C. diff testing and consistent with the most recent IDSA recommendations, we established several pre-agreed criteria for testing to ensure that we improve the pretest likelihood of CDI in the patient population that we’ re testing,” said Kociolek.“ So, we would use only an unformed stool for testing. Our laboratory would be the gatekeeper of that; we’ d restrict testing in children under the age of 1, and we would not perform repeat testing within seven days of a previous because of the low likelihood of the new result being different than the first one. We were still seeing colonization and unnecessary treatment, so, following off a study that Stanford did in their children’ s hospital, we’ ll do a modified two-step where for patients that have a PCR with a high cycle threshold-- that means they have a low burden of C. diff in their stool-- we will follow up with a toxin test, anticipating that it’ s going to be negative in essentially all circumstances, which we’ ve confirmed with real-world use of this to provide that additional laboratory evidence to the
16 • www. healthcarehygienemagazine. com • jan-feb 2026