Frozen fecal transplantation effective at providing relief to C. diff patients

Frozen fecal transplantation is effective at providing relief to Clostridium difficile (C. diff) patients, according to a new study co-authored by University of Guelph researchers.

The study found that frozen fecal microbiota transplantation (FMT) is just as effective as fresh FMT for treating infections caused by the bacterium C. diff, which can cause severe and potentially fatal bouts of diarrhea.

The bug is often picked up in hospitals and nursing homes. An estimated 300,000 Canadians contract C. diff each year, and 30,000 will die from it.

The study, led by researchers from McMaster University, was just published in the Journal of the American Medical Association.

The researchers used FMT to treat patients through an enema.

Overall, 83 per cent of patients receiving frozen material recovered compared to 85 per cent of those receiving fresh material.

"Frozen is just as good as fresh in terms of efficacy, and there were no significant differences in ensuing adverse events, which were relatively minor," said Prof. Peter Kim, Department of Mathematics and Statistics, who was senior author of the paper.

Kim designed the study, supervised patient recruitment, collected data and analyzed the findings.

He was joined in the study by Prof. Scott Weese, Pathobiology. Weese's lab is one of few that perform C. diff culture and typing.

"Understanding the types of C. diff that are involved and whether they impact response to treatment is important," said Weese.

"Knowing how the gut microbiota responds to fecal transplants is critical since that's what the treatment targets. It's not designed to kill C. diff, but instead it helps restore the microbiota to a state whereby it is able to prevent C. diff from causing disease."

Frozen fecal matter saves time in screening and preparation, and can be easily stored, said Kim.

"When using fresh fecal matter, there needs to be synchronization with the donor, patient, laboratory personnel and physician since preparation has to take place over a short window of time," he said.

"Some hospitals have their own laboratories, so it is not as inconvenient, but it still takes time. It would also pose considerable challenges for remote locations. By using frozen fecal matter, hospitals would have a screened, ready-to-use supply."

Kim said the five-year-long study has supplied lots of data that the researchers are only starting to analyze.

"We have sequenced about 25 per cent of the available samples to try and understand how the gut microbiome undergo changes as patients progress, and we also want to look at the links between the gut and the brain, the so-called gut-brain axis," he said.

"We have collected a lot of clinical, demographic, health-related quality of life and microbiome data over the course of this study. There are many fascinating scientific and medically related questions to investigate."