The problem with fecal transplants

Over the past few years, we've linked to a couple of stories about fecal transplants—a real medical procedure where doctors take a donor stool sample, dilute it, and inject it into the colon of a patient. It sounds gross. But it appears to be incredibly effective at treating certain intestinal issues.

Basically, the fecal transplant is really a bacteria transplant. A fresh set of healthy bacteria can fix problems that aren't reliably treatable any other way. On the other hand, most of this information comes from anecdotal evidence. Fecal transplants haven't gone through any large-scale, randomized clinical trials. Until that happens, most doctors won't offer the procedure and insurance won't cover it. That makes sense. We rely on clinical trials to separate treatments that work from treatments that just appear to work. The problem with fecal transplant, though, is that it doesn't fit into any of the bureaucratic categories necessary to get a trial like that approved.

Over on Scientific American, Maryn McKenna has a great feature about fecal transplants—their promise, what we don't know about them, and what's keeping them from becoming a mainstream treatment.

Marion Browning of North Providence, R.I., was at her wit's end. The 79-year-old retired nurse had suffered from chronic diarrhea for almost a year. It began after doctors prescribed antibiotics to treat her diverticulitis, a painful infection of small pouches in the wall of the colon. The regimen also killed friendly bacteria that lived in Browning's intestines, allowing a toxin-producing organism known as Clostridium difficile to take over and begin eating away at the entire lining of her gut … In the fall of 2009 Browning performed the bowel-cleansing routine that precedes a colonoscopy, while her son took an overnight laxative. Kelly diluted the donation, then used colonoscopy instruments to squirt the solution high up in Browning's large intestine. The diarrhea resolved in two days and has never recurred.

Browning is not alone in being a success story. In medical journals, about a dozen clinicians in the U.S., Europe and Australia have described performing fecal transplants on about 300 C. difficile patients so far. More than 90 percent of those patients recovered completely, an unheard-of proportion. "There is no drug, for anything, that gets to 95 percent," Kelly says. Plus, "it is cheap and it is safe," says Lawrence Brandt, a professor of medicine and surgery at the Albert Einstein College of Medicine, who has been performing the procedure since 1999.

So far, though, fecal transplants remain a niche therapy, practiced only by gastroenterologists who work for broad-minded institutions and who have overcome the ick factor. To become widely accepted, recommended by professional societies and reimbursed by insurers, the transplants will need to be rigorously studied in a randomized clinical trial, in which people taking a treatment are assessed alongside people who are not. Kelly and several others have drafted a trial design to submit to the National Institutes of Health for grant funding. Yet an unexpected obstacle stands in their way: before the NIH approves any trial, the substance being studied must be granted "investigational" status by the Food and Drug Administration. The main categories under which the FDA considers things to be investigated are drugs, devices, and biological products such as vaccines and tissues. Feces simply do not fit into any of those categories.

Image: Toilet Roll, a Creative Commons Attribution (2.0) image from smemon's photostream