A study in the journal Microbiome has found that changes to a patient’s microbiome that are characterized as healthy after fecal microbiota transplantation (FMT) may be sustained for up to 21 weeks post-transplant.

Michael J. Sadowsky, PhD, of the University of Minnesota, and colleagues collected fecal samples from four patients with multiply recurrent Clostridium difficile infection (CDI) that were refractory to antibiotic therapy prior to and following their FMT. All patients received fecal microbiota from the same pre-qualified donor; three patients received freshly prepared microbiota from fecal matter and one received fecal microbiota that was previously frozen. Pre- and post-transplant fecal microbial communities from the four patients were compared to microbiota across body sites in the Human Microbiome Project (HMP) database, as well as from 10 additional patients with recurring CDI. Patient samples appeared to retain changes in their microbiome for up to 21 weeks after transplantation and remained within the larger cloud of fecal microbiota characterized as healthy by the HMP.

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With the short- and long-term changes in the fecal microbiome after transplantation, the diversity and types of microbiomes fall into the healthy characteristics of the HMP. Because the Food and Drug Administration (FDA) has declared fecal microbiota to be a drug, the dynamic nature of fecal microbiota in both the donor and recipients could indicate that this type of regulation may not be applicable for fecal transplants, the authors add.

For more information visit MicrobiomeJournal.com.