Every time we take antibiotics-whether it's for strep throat, urinary tract infections, or pneumonia -there is a slim chance that "bad" bacteria can move in and wreak havoc on our digestive tracts.
Clostridioides difficile (C. diff.) is one of the most common invaders and can cause post-antibiotic diarrhea and even life-threatening damage to the colon. With about 500,000 Americans contracting the infection every year, especially those who are immunocompromised or over the age of 65, researchers have been working hard to develop effective preventative treatments.
Trevor Barlowe, MD
However, a new study led by Sarah McGill, MD, a gastroenterologist and endoscopist at UNC Health, and Trevor Barlowe, MD, a gastroenterology fellow at the UNC School of Medicine, has found that a newly-approved treatment for C. diff. infection, called fecal microbiota spores, may be associated with a particularly harmful rebound of infection, compared to traditional therapy. Their results were published in Clinical Gastroenterology & Hepatology.
"It is exciting to have new treatments for a particularly hard bug to treat," said Barlowe. "But it's important to compare new therapies to our standard of care over long follow-up periods. We found that both therapies were effective, but, in the rare events of recurrence, there were more severe recurrences in the patients who received spores."
Traditional vs. Novel Therapy
Fecal microbiota transplant has been used as the traditional treatment for C. diff. infection for a little over a decade.
The procedure, which is done via colonoscopy, involves transplanting a small sample of stool from a healthy person into a colon infected with C. diff. to help restore balance in the gut, Although the therapy is safe, it is only approved for investigational use by the U.S. Food and Drug Administration (FDA).
In 2023, a novel non-invasive, oral treatment called fecal microbiota spores received approval from the FDA. Fecal microbiota spores are taken in pill-form three times a day post-antibiotic treatment to prevent a C. diff. infection from re-occurring.
UNC Medical Center in Chapel Hill, which is one of few medical centers in the region that offers microbial therapeutics for C. diff. infection, began integrating the new therapy in the hospital as soon as it was approved. However, there was a lack of data directly comparing patient outcomes from these two treatment types.
Results from the Comparative Study
Sarah McGill, MD, Msc
McGill, who has years of experience in treating patient with C. diff. at UNC Health, recruited Barlowe to perform a comparative study on adult patients who received fecal spores and colonoscopy-administered fecal transplant at UNC Medical Center. Using patient data from electronic medical charts, the researchers tallied the number of C. diff reinfections within one year of treatment.
Their center-based study found that both methods were efficient at preventing recurrent infection. However, in the rare patients who had a recurrence, the patients who received fecal spores were more likely to develop severe disease, called "fulminant C. diff infection."
Of the 28 patients who received fecal spores, two were admitted to the hospital with fulminant infection. In comparison, there were zero cases of fulminant infection in the 102 patients who received fecal transplant via colonoscopy.
"We found that fecal spores worked really well to protect people from a recurrence of C. diff," said McGill, who is also a professor of medicine. "But among the people who did recur, they had severe disease with sepsis. That's something that we did not see in our many years of treating patients with fecal transplant via colonoscopy."
Implications for Future Treatment
Both Barlowe and McGill urge other physicians and centers to closely monitor patients post-treatment for recurrent C. diff, no matter what type of treatment is used. The findings are significant, as traditional fecal transplant is no longer available at almost all medical centers nationwide, due to recent pressure from the FDA.
The duo notes that the therapy is not appropriate for all patients with recurrent C. diff infection.
"Hopefully, our findings can help other providers and regulators understand that both of these treatments have really important roles in certain patients," said Barlowe. "If somebody was really sick in the ICU with C. diff, then that person would be a good candidate to get a fecal transplant. Whereas patients who are outpatient and healthier might be able to take the microbial spores."
