The “poop” on treating C. difficile

The Tablet

We have all experienced this before: a patient has read or heard about some radical new treatment in the media and wants to know what their pharmacist thinks about it. Recently, we had several physicians and patients ask us about one therapy that has been making headlines in the news: an oral medication made of stool (or “poop”) in the treatment of Clostridium difficile (C. difficile). Reports of this new treatment were seen in major publications such as The Vancouver Sun, CBC News, and USA Today. This was particularly relevant, as over the past year we have seen many patients suffering from C. difficile-associated diarrhea with recurrent, severe symptoms despite standard treatment with metronidazole or vancomycin.

C. difficile is an anaerobic, gram-positive bacteria that normally colonizes the intestinal tract. It can overpopulate the gut after normal gastrointestinal flora is altered, commonly after antibiotic use. It can cause a range of illnesses from mild diarrhea to severe pseudomembranous colitis. Relapsing C. difficile occurs in up to 25 per cent of patients treated with either metronidazole or vancomycin. Ten per cent of patients will unfortunately suffer from multiple relapses. Patients who experience multiple relapses of C. difficile will usually follow a familiar timeline of repeated antibiotic courses for longer durations of treatment.

The idea of using stool in an oral preparation is currently being studied through innovative research in Calgary. The capsules contain material from stool of healthy donors, which are processed to isolate the bacteria within the fecal matter. The resulting concentration of isolated bacteria is then formulated into capsules, which are encased in three layers of gelatin. The gelatin layers are designed to protect the capsule past the acidic stomach environment and into the colon where the payload can be delivered. Despite promising observational evidence that suggests a 100 per cent cure rate with minimal side effects, the capsules are still in the experimental phase and are unfortunately not yet commercially available. There is a need for ongoing research and randomized controlled trials to support the use of this therapy at this time.

A similar alternative in the treatment of recurrent C. difficile is the use of fecal microbiota transplantation (FMT). FMT is the transplantation of donor stool into the bowel of the patient, usually via enema or a colonoscope by a specialist.

There are multiple different regimens that can be tried; one method includes:

  1. Pre-treatment with vancomycin 500 mg twice daily for seven days, followed by oral lavage with an electrolyte purgative (such as GoLYTELY).
  2. 300 gms of donor stool suspended in 300 mL of sterile normal saline, then homogenized in a blender to liquid consistency.
  3. Enema administered once daily for five days. Patients are encouraged to retain the enema for at least six hours. Loperamide 2 mg can be given to help facilitate retention of the enema.

A recent meta-analysis showed that FMT can be effective in the treatment of recurrent C. difficile-associated diarrhea with benefits that may last up to nine years after therapy. Unfortunately it seems that the available evidence is not enough to support routine FMT at this time. 

Since oral stool medications are not yet available for purchase, we had to recommend alternatives for our patients, which included a second course of antibiotics as well as a course of Saccharomyces boulardii (yeast probiotic). Oral rehydration solution was always encouraged to prevent dehydration.

What experience have you had with treating C. difficile, and would you be willing to try a course of oral stool medications? Visit us on Facebook at Clinicare Pharmacists to join the discussion.

Larry Leung and Jason Min are directors of Clinicare Pharmacists Inc. and lecturers at UBC. They have a passion for interdisciplinary care and the development and implementation of innovative clinical pharmacy services in the community.

References

  1. UpToDate Topic: Fecal microbiota transplantation in the treatment of recurrent Clostridium difficile infection. Accessed from: http://www.uptodate.com/contents/fecal-microbiota-transplantation-in-the-treatment-of-recurrent-clostridium-difficile-infection?source=search_result&search=fecal+transplant&selectedTitle=1~5
  2. http://www.cbc.ca/news/canada/calgary/poop-pills-can-treat-c-difficile-calgary-doctor-says-1.1895079
  3. Kassam Z, Lee CH, Yuan Y, Hunt RH. Fecal microbiota transplantation for Clostridium difficile infection: systematic review and meta-analysis. Am J Gastroenterol. 2013;108(4):500.
     

This article is featured in The Tablet. The Tablet features pharmacy and industry news, profiles on B.C. pharmacists, information on research developments and new products.