Clostridium difficile (or C. diff) infection has gotten a lot of press in the last few years and has recently been named as one of the top three urgent antibiotic resistance threats by the Center for Disease Control and Prevention (CDC). C. diff is a bacteria that is an opportunist, it often lurks in hospitals where it is transmitted from patient to patient often on the hands of health care workers. When it gets ingested by someone it waits patiently until the person is given antibiotics which kill the normal bacteria in that person’s colon, then C. diff can then take up residence and flourish. It produces toxins that cause damage to the bowel which leads to diarrhea and in severe cases can lead to severe inflammation of the colon requiring surgery to remove the infected bowel. From an evolutionary perspective (assuming you believe in that sort of thing), C. diff, like many other pathogens, is quite clever. Its only purpose in life it to go forth and multiply and it relies on human hosts to do this – and what better way to transmit and infect others than by causing wicked diarrhea….but that is for another blog.
People who get this infection are miserable. They have pain and diarrhea multiple times a day. While most people can be treated with more (but different) antibiotics, some can have recurrent bouts of infection and some have chronic or “refractory” infections that are very difficult to cure. Over the last decade a simple but effective treatment has gained increasing acceptance and coincides with an explosion in research into the diversity of bacteria that live in or on us: stool transplantation. Stool transplantation (which some have referred to as “repoopulation”) is exactly what it sounds like. You have a donor (preferably someone you know well like a spouse) who supplies “healthy” stool which is then blended into a poop slurry and put back into the recipient using a scope up the back passage where they spray it on the colon like Miracle-Gro on a garden. Alternatively the slurry can be fed through a tube that is inserted down the throat and into the recipient’s stomach. This simple procedure has been very effective at curing patients who have been miserable for months because they cannot get rid of their C. diff diarrhea. However, even when the definitive scientific trials are published will this become a common treatment option? Currently stool transplants are not available in Nova Scotia but doctors are working on developing guidelines and a protocol so it can be an option in the future. All that said, I think that people may still be reluctant to embrace stool transplantation.
The problem is the “ick” factor. Poop is “dirty”, it smells, it can certainly transmit disease (Salmonella, Shigella just to name a few) and people are embarrassed by it. But our poop is very important to our bodies. Each of us has billons of bacteria in our gut that help to keep us healthy. This microbial flora or microbiota is made of up thousands of different species of bacteria, some of which we cannot even grow in the lab. It is a unique signature and the composition of the bacterial population is different in everyone. It is thought that our microbiota starts when we are born and exposed to our mother’s bacteria. As children we constantly sample the environment. How often have you seen babies put things in their mouth? People have assumed that this oral sensing was part of how a child learns about his environment. What if this is our inherent way to ensure we are increasing our biodiversity and maintaining a balanced bacterial environment. But what happens when this microbiota balance is disrupted? Alterations in the diversity of this flora can have significant impact on many different diseases from inflammatory bowel diseases to other autoimmune conditions. There is even data to suggest that the microbiota in your gut can influence how fat you are. Studies have shown that if you have stool from a skinny mouse and put it in an obese mouse it can influence their body weight even when they are on the same diet. While I would not advocate stool transplantation as a form of weight management, you can see the potential for this therapy. If you can repoopulate your colon, you could logically regenerate your microbiota and get back to a healthy state. In the future, one could envision submitting your poop to a “bank” of stool samples that could be used in the event that you get C.diff or another modifiable illness. Have you ever wondered why a dog eats his own poop? Maybe it is because it is actually keeping them healthy.
~ Todd F. Hatchette MD FRCPC
Chief,Division of Microbiology
Department of Pathology and Laboratory Medicine
Capital District Health Authority
Associate Professor, Dept of Pathology, Dalhousie University