Study Identifies Key Organisms for the Treatment of Clostridium difficile

A new study found that heterologous fecal microbiota transplantation (FMT) was more successful than autologous fecal microbiota transplantation in patients with Clostridium difficile. However, researchers noticed that participants who were cured by their own stool samples had greater abundances of Clostridium XIVa Clade and Holdemania bacteria prior to the FMT.

For their study, researchers conducted a randomized clinical trial with 24 participants who had Clostridium difficile. Participants were on a regimen of vancomycin for 10 days before the transplant, and stool samples were collected less than 6 hours before the FMT. Fourteen participants received colonoscopic autologous FMT of their own stool, and 10 participants received heterologous FMT from a healthy donor. Fecal samples from participants were collected at 2 and 8 weeks after the transplantation. The participants who experienced recurrence were provided a second course of vancomycin and treated with another FMT using a healthy donor stool sample.
_________________________________________________________________________________________________________________
RELATED CONTENT
Researchers Discover How C. difficile Disrupts the Gut
Could Fecal Microbiota Transplant Reduce C. difficile Recurrence?
_________________________________________________________________________________________________________________

The microbiomes of donor and participants were characterized using Illumina next-generation sequencing of the 16s rRNA gene. Researchers used the Shannon index and abundance-based coverage estimate metric to measure alpha diversity in all the samples.

Donor samples and samples of participants treated by heterologous FMT had greater alpha diversity than pre-transplant and failed autologous FMT samples. Samples from participants who were cured by autologous FMT did not differ from samples of participants who were treated with heterologous FMT. Researchers noticed that subjects cured by autologous FMT had greater amounts of Clostridium XIVa Clade or Holdemania in the Erysipelotrichaceae and Parasutterella families in their samples prior to receiving FMT treatment.

The results of this study suggested that bacteria associated with secondary bile acid metabolism could potentially provide resistance to infection and that complete transfer of healthy donor microorganisms was not necessary to resolve [Clostidium difficle] following unsuccessful antibiotic treatment.

—Melissa Weiss

Reference:

Staley C, Kelly CR, Brandt LJ, Khoruts A, Sadowsky MJ. Complete microbiota engraftment is not essential for recovery from recurrent Clostridium difficile infection following microbiota transplantation [published online December 20, 2016]. mBio. doi:10.1128/mBio.01965-16.