In this article, the author says that one must do $500 worth of testing on the donor, then make up a particle free stool slurry of stool and non-bacteriostatic saline under a hood (due to the biohazard aspects of making poop soup) filter it and instill the mixture via a colonoscope to the patient who has taken 3 gallons of polyethylene glycol solution and preferably had only clear liquids for 2 days. He says that the procedure should only be done for patients who have had C. difficile for 3 months which has not responded to antibiotic therapy.
There is no evidence to suggest that giving donor feces by colonoscopy is any better than giving it by low volume enema, at home, or by nasogastric tube. Colonoscopy carries significant risks: anesthesia is risky and colonoscopes can cause perforation and bleeding. Colonoscopies are expensive. The recent article in the New England Journal used a naso-duodenal tube, not a colonoscope.
There is reasonable evidence that fecal transplant is effective for treatment of ulcerative colitis, an autoimmune disease of the colon that causes chronic disability, colon cancer and internal bleeding. Acute C. difficile claims many lives, and there is abundant experience of treating it with fecal transplant. Limiting this therapy to chronic cases seems a bit excessively restrictive.
The author of the Medscape article notes that some of the patients in the recent trial of fecal microbiota transplantation developed new diseases, some of them autoimmune, which might have been related to the transplants. It seems unlikely, but I would also wonder whether some of the patients found that more problems than just their C. difficile were resolved. Much is still not known and will only be revealed as more research is done with larger groups of patients.
As far as the $500 of tests that need to be done on the donor, I wonder if perhaps some of these could be eliminated. Clearly the donor should be checked for body fluid transmitted diseases such as HIV and hepatitis, though a family donor of known low risk (a child, for instance) might safely be presumed to be uninfected. Extensive stool testing for bacteria and parasites in a donor with no intestinal difficulties might also be unnecessary, especially if that person's history was well known.
As far as the actual logistics of delivering donor stool to recipient colon, I suspect nothing more than a commercially available enema bag and tubing would be necessary. The soup to be delivered could probably be easily and cleanly mixed up in a Ziploc bag, with no need for a blender. As far as preparation with a clear liquid diet and gallons of polyethylene glycol, I am curious to see evidence that supports this (I don't think there is any, yet). Cleaning out the bad bugs seems like a good approach, but patients get very weak after a standard colonoscopy prep so a prep that includes days of fasting plus more polyethylene glycol might lead to its own problems.
I am starting to think about the nuts and bolts of all of this because, as a hospital physician, I will soon be faced with a patient for whom fecal transplant will be an obvious life-saving intervention, and I will have to figure out how to do it with as little fuss as possible. It will be unethical for me to allow someone to die when antibiotics fail, as they so often do, when evidence shows that a fecal enema would probably be curative.
