Vancomycin suppression goes with fewer repeat C difficile infections in veterans records

Keeping people on a steady daily course of oral vancomycin, rather than tapering it off, went with fewer later bouts of Clostridioides difficile infection in a review of Veterans Health Administration records. The vancomycin suppression group also showed no clear rise in vancomycin resistant Enterococcus. The work was presented at the IDWeek meeting in Washington and has not been published in full, so the numbers come from a conference talk.

What the records showed

Samir Memic, a research associate in Cleveland at the Northeast Ohio VA system, and colleagues reviewed records of veterans who tested positive for C. difficile and were treated with oral vancomycin between 2015 and 2024. The full pool held 38,182 patients. The team then narrowed it to 2,554 people who stayed on the drug for at least 90 days, and split them by regimen. Most, 2,230, had a taper, in which the amount is reduced step by step. The remaining 324 were on continuous daily treatment for at least 60 days with no taper or pulsing, the pattern the team calls vancomycin suppression. Median age in that group was 77 years and 92% were men, so the findings describe an older, mostly male population.

None of the 324 people on steady treatment developed a C. difficile infection while they were taking it. After the drug stopped, the risk of a new bout was lower than after a taper, with a hazard ratio of 0.29 and a confidence interval from 0.18 to 0.46. Longer treatment went with lower risk: people kept on suppression for three to six months were more likely to relapse than those treated beyond six months. Median time on the drug in this group was 510 days. Memic said the approach may be an option for selected patients with repeated infections when other strategies are not feasible, and that more work is needed on who should be picked and how long treatment should run.

The resistance question behind vancomycin suppression

The worry with months of an oral glycopeptide is that it clears away protective gut bacteria and leaves room for enterococci that no longer respond to the drug. In this cohort that did not show up. Positive clinical cultures for vancomycin resistant Enterococcus were found in 2.8% of the suppression group and 3.7% of the taper group. Both figures come from cultures taken in the course of care rather than from routine screening of every patient, so they count infections and samples that clinicians thought worth sending, not carriage in the gut. The gap between the two regimens was also small and ran in the direction of the longer treatment, which is not what the usual worry about resistance would predict.

Positive clinical cultures for vancomycin resistant Enterococcus were found in 2.8% of the suppression group and 3.7% of the taper group.

That distinction matters because resistant organisms often sit silently in the bowel long before they cause disease. Studies that swab stool find far more carriage than culture records do. The comparison here is also between two vancomycin regimens, not between vancomycin and nothing, so both arms had long exposure to the drug. Readers who follow the wider search for antibiotics that still work against hospital organisms may remember the Roche compound described in our report on a ring shaped peptide antibiotic aimed at Acinetobacter baumannii. Enterococcus resistance has no such new answer in late development, which is part of why a result suggesting that months of vancomycin did not drive it is worth checking properly.

Who ended up on long treatment

A chart review of 113 of the suppressed patients explains how they got there. In 40.7% of those cases a faecal microbiota transplant was ruled out, because the person was on systemic antibiotics, had a short life expectancy, or had already failed the procedure. Another 16% were on the drug temporarily while waiting for a transplant or for surgery, chemotherapy or treatment that suppresses the immune system. American College of Gastroenterology guidance already suggests considering prolonged low amounts of the drug for people with repeated infections who cannot have a transplant, so the practice described here follows existing advice rather than introducing something new.

Context matters for how common the problem is. Up to 30% of patients may have another episode after their first, and the risk climbs with each one, reaching around half after several. Faecal transplant is the most effective option for repeated disease, with alternatives including vancomycin tapers and pulses, vancomycin followed by rifaximin, and fidaxomicin. None of those options works for everyone, which is how a long steady course became a last resort for some patients. The study was reported by MedPage Today from the IDWeek presentation. Our microbes section follows the resistant organisms behind this kind of treatment choice.

What the presentation cannot settle

The design limits every conclusion. This was a look back at records, not a trial, and nobody was assigned to one regimen by chance. Doctors chose steady treatment for particular patients, and those reasons may themselves affect the risk of relapse. Co-author Curtis Donskey of the Cleveland VA Hospital noted a measurement problem that cuts the other way: most patients on steady treatment had no diarrhoea and so were never tested for C. difficile. In a chart review the team found five or six who did develop diarrhoea and were tested, and all were negative. Still, infections that are never tested for cannot appear in the count.

Conference abstracts are also early work. They are not peer reviewed in the way a journal paper is, the full methods are not public, and the figures can change before publication. The table above lists what was reported from the podium. Two further gaps are worth naming. The analysis covers one health system with an unusual population, so the results may not carry to younger patients or to women, who made up 8% of the group. And resistance was measured only through clinical cultures during care, which leaves the central safety question about vancomycin suppression open until someone screens stool systematically.

Conclusion

In Veterans Health Administration records, vancomycin suppression went with fewer repeat C. difficile infections than a taper and no rise in resistant Enterococcus cultures. The work is retrospective, presented at a meeting, and drawn from an older male population, so it supports a treatment already in guidance rather than changing practice. Stool screening and a randomised comparison would show whether the resistance result holds.

Source Memic S et al. Vancomycin suppression for multiply recurrent Clostridioides difficile infection, presented at IDWeek 2026, Washington, reported by MedPage Today on 23 October 2026

Amino Weekly reports research. It is not medical advice and never gives doses.