How fecal microbiota transplants help re-establish a healthy gut microbiome
There is a rapidly growing awareness â€“ in both the medical practice and the general population â€“ of the importance of the gut microbiome and its potential impact on total body health. Much of this interest is focused on re-establishing a healthy gut microbiome through various therapies, including fecal microbiota transplant (FMT).
This has become increasingly important with the rise in clostridium difficile (c.diff) infections related to increased antibiotic use. Knowing more about the theory, practical application and controversies around FMT can help you better understand this type of therapy.
One of the earliest mentions in modern medical literature of FMT is from 1958, with an attempt to treat pseudomembranous enterocolitis with a fecal enema. Since then, the most well-studied disease that FMT has proven its efficacy is in the treatment of recurrent c.diff. The current indication for FMT is for patients who have had three or more c.diff recurrences despite appropriate antibiotic therapy.
FMT can be extremely effective, with success rates as high as 92 percent. Head-to-head studies of FMT vs vancomycin (Vancocin) have demonstrated that FMT was more effective than vancomycin.
Once FMT has been identified as an appropriate therapy, we need to address the delivery method. Originally, retention enemas (at times combined with at-home preparation during the period when FMT required exemption from the FDA), were one of the most used methods. Even as recently as five years ago, some FMT treatment was done at home with a blender (preferably disposable), a community-sourced donor (family) and an enema bag.
Today, FMT may be provided via colonoscopy, nasogastric tube or stool pills. Since there are no robust studies comparing the efficacy of different delivery methods, patients are likely best served by clinicians with access to several different approaches and the willingness to tailor it to the individual patient.
The question of identifying a stool donor must also be addressed. Previously, stool donors were sought from the patientâ€™s healthy family, with their stool undergoing screening for possible infectious pathogens prior to being used for FMT.
Currently, the more common approach is to use a commercially sourced product that is delivered frozen, reconstituted immediately before use and instilled via the chosen method.
Several companies are working â€“ so far, unsuccessfully â€“ to isolate and concentrate the particular bacteria or compounds that are therapeutic. Further work is underway to isolate specific individuals whose stool appears to be more beneficial for specific disease states. Much of this effort is focused on the treatment of inflammatory bowel disease.
It has been postulated that the gut microbiome could hold the key to obesity, depression, inflammatory bowel disease and many other diseases. These have not been well studied, and use of FMT as treatment can be controversial.
But as more is understood about how the gut microbiome plays a part in the bodyâ€™s overall health, all of us will need to start paying even more attention to the rapid progress being made in this arena so that we can offer our patients the most efficacious treatment options.
1. Quraishi MN, Widlak M, Bhala N, et al. Systematic review with meta-analysis: the efficacy of faecal microbiota transplantation for the treatment of recurrent and refractory Clostridium difficile infection. Aliment Pharmacol Ther 2017;46:479-493.
2. Fischer M, Sipe B, Cheng YW, et al. Fecal microbiota transplant insevere and severe-complicated Clostridium difficile: a promising treatment approach. Gut Microbes 2017;8:289-302.