Fecal microbiota transplantation (FMT) appears safe and effective as a treatment for most Clostridioides difficile infections as it is currently being administered, researchers say.
“We actually didn’t see any infections that were definitely transmissible via fecal transplant,” Colleen Kelly, MD, an associate professor of medicine at Brown University in Providence, Rhode Island, told Medscape Medical News.
The finding, published online today in the journal Gastroenterology could allay concerns about a treatment that has yet to gain full approval by the US Food and Drug Administration (FDA), despite successful clinical trials.
C diff infections are common and increasing in the United States, often can’t be cured with conventional treatments such as antibiotics, and can be deadly.
Transplanting fecal matter from a donor to the patient appears to work by restoring beneficial microorganisms to the patient’s gut. The procedure is also under investigation for a wide range of other ailments, from irritable bowel syndrome to mood disorders.
But much remains unknown. Researchers have counted a thousand bacterial species along with viruses, bacteriophages, archaea, and fungi in the human gut that interact in complex ways, not all of them beneficial.
The FDA has not enforced regulations that would prohibit the procedure, but in March, it warned about infections with enteropathogenic Escherichia coli (EPEC) and Shiga toxin-producing Escherichia coli (STEC) following fecal transplants.
As a result of these reports, and the theoretical risk of spreading SARS-CoV-2, OpenBiome, the largest stool bank in the United States, has suspended shipments except for emergency orders, and asked clinicians to quarantine any of its products they already have on hand.
In the meantime, long-term effects of the treatment have not been well documented. And clinical trials have excluded patients who might benefit, such as those who have been immunocompromised or have inflammatory bowel disease.
National Registry Follows Patients Outside Clinical Trials
To better understand how patients fare outside these trials, the American Gastroenterological Association Institute and other organizations developed a national registry, funded by a grant from the National Institute of Allergy and Infectious Diseases.
The current report summarizes results on 259 patients enrolled between December 5, 2017 and September 2, 2019 at 20 sites.
At baseline, 44% of these patients suffered moderate and 36% mild C diff infections. The duration of the diagnosis ranged from less than 1 week to 9 years, with a median duration of 20 weeks. They ranged from one to 15 episodes with a mean of 3.5.
Almost all had received vancomycin, and 62% had at least two courses. Forty percent had received metronidazole and 28% had received fidaxomicin.
Almost all participants received stool from an unknown donor, mostly from stool banks, with OpenBiome accounting for 67%. Eighty-five percent of the transplants were administered through colonoscopy and 6% by upper endoscopy.
Out of 222 patients who returned for a 1-month follow-up, 90% met the investigators’ definition of cure: resolution of diarrhea without need for further anti-C diff therapy. Ninety-eight percent received only one transplant. An intent to treat analysis produced a