December 09, 2015
2 min read

Guest commentary: The exciting future of fecal microbiota transplant

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In this guest commentary, Ari Grinspan, MD, assistant professor of medicine and gastroenterology at Icahn School of Medicine at Mount Sinai, and director of gastrointestinal microbial therapeutics at The Mount Sinai Hospital, discusses the past, present and future of fecal microbiota transplant, as well as his own experience with the procedure.

To put it very simply, our microbiome is the co-existence of the microbes, symbiotic and pathogenic, that live within us. Microbiota are the bacteria that live in us, and to say there are “a lot” is an understatement. In fact, living inside our bodies there are 10 times more bacterial cells than human cells.

Ari Grinspan

Dysbiosis is the disruption in gut microbiota that can be caused for many reasons, such as antibiotic use and IBD flare-ups. These conditions can make people susceptible to Clostridium difficile infection — a bacterium that can cause diarrhea and very serious inflammation of the colon. This is a bad bug and a costly one too — antibiotics and hospital stays aren’t cheap. As a nation we are spending billions a year treating C. difficile and roughly 65% of patients will recur after a third treatment of antibiotics.  

So why does this happen? By looking at patients’ gut microbiome, we have seen dramatic changes in their microbiota portfolio. C. difficile takes over and the healthy and diverse bacteria become diminished.

But how did the modern world begin treating and even curing patients with C. difficile infections with human feces? Actually it started back in 4th century China, when practitioners would give “yellow soup” to cure different GI ailments. Then in 1958 in Denver, Colorado, a physician came across some veterinarian literature that referred to treating sick animals with healthy animal stool. Then in 1983, the first case of a fecal transplantation was recorded in Scandinavia.

In 2013, I performed the first FMT at The Mount Sinai Hospital, and ever since then my results have been staggering. Thus far, I have performed FMTs on more than 100 patients with a 92% success rate, and Mount Sinai has become a leading referral center in the tri-state area for FMTs for C. difficile infections.  

To perform an FMT, a healthy stool sample gets diluted in saline and then infused into a patient’s colon during a colonoscopy — and that’s basically it. Critically though, the stool sample must come from a qualified and thoroughly screened donor in the same manner as a blood donor, but with a GI questionnaire relating to gastroenterology health and history such as ulcers, colon cancers and polyps.

As of yet, we don’t know exactly why it seems to work so well, but — as I learned from Colleen R. Kelly, MD, from Brown University — I tell my patients, sometimes weeds grow on healthy grass. You can try and remove the weeds using weed killers, but if your lawn is more weed than grass, sometimes you just have to start from scratch and re-sod the entire lawn with healthy lush grass.

Perhaps the high success rate of FMTs in curing C. difficile via FMT stems from an increased bacterial competition for nutrients and dominance, or an increased secondary bile acid production that inhibits the C. difficile bacterial growth, or perhaps by introducing local antimicrobials that kill the C. difficile bug and thereby increase the normal healthy microbiota.

After analyzing the microbiota of an FMT patient post-procedure, we have seen that their gut bacteria appeared remarkably similar to those of the healthy donor’s with more diversity. These surprising results have led to some possible future implications that are quite exciting as dysbiosis may be associated with autism, fatty liver disease, diabetes, IBD, and even obesity.

Clinical trials are currently underway in a variety of research in these areas as well as is the fecal matter delivery system itself — a so-called “Poop Pill” is already in the works. So stay tuned as we unlock the power of poop.

Disclosures: Grinspan reports no relevant financial disclosures.