THE BLOG

How Bacteria in Our Gut Can Guide GI Treatment

May 12, 2014 | Updated Jul 12, 2014

The community of bacteria and other organisms that lives in our intestinal tract -- known as the gut microbiome -- has co-evolved with us and can be considered a symbiotic partner helping us perform everyday functions, such as eating our lunch. In fact, we wouldn't be able to properly digest some of the foods we eat without the assistance of these bacteria. The microbiome also plays a role in our body's immune system and can be manipulated to help fight off infection. For example, we've been able to harness these bacteria for the treatment of C. difficile using a treatment called fecal microbiota transplant (which I wrote about in detail here).

Even though greater access to mass DNA sequencing technology and the emergence of bioinformatics has given us the ability to study the four pounds of microorganisms that make up the microbiome in greater detail, there's still much more that we can learn about the body's "unsung organ."

This week at Digestive Disease Week (DDW), the world's largest gathering of physicians and researchers in the fields of gastroenterology, hepatology, endoscopy and gastrointestinal surgery, my colleagues and I came together to share new research about the microbiome that can potentially give patients with digestive diseases hope for new treatments.

Dirk Gevers, Ph.D., of the Broad Institute of MIT and Harvard, and his team compared the microbiome of early-onset Crohn's patients, who were treatment naïve, with patients who do not have inflammatory conditions. They found in a forthcoming study that the microbiome of these Crohn's patients had an increased abundance in certain bacteria and a decreased abundance in other bacteria. Interestingly, they also found that antibiotic use actually amplifies these bacterial changes, introducing even great imbalance.

In another forthcoming comparison study, Govind Makharia, M.D., looked to see if there were any differences between the gut microbiota patients with celiac disease who had not received treatment and their parents, siblings or other first-degree relatives. He saw that, in celiac patients, there was a reduction in the richness of the bacteria and an increase in disease-causing bacteria.

The data from these treatment naïve studies show great promise for patients with Crohn's and celiac. If we are able to take these types of findings and develop more effective treatments for digestive diseases, patients will be able to lead more normal lives.

I was also intrigued by a forthcoming study conducted by Josie Libertucci, a Ph.D. student from McMaster University. Her team compared the fecal microbiota of ulcerative colitis patients who responded to fecal microbiota transplant (FMT) to those patients who did not respond well to FMT. They found some common microbial characteristics in the patients who responded well.

These data are intriguing because FMT is currently only approved for the treatment of C. difficile. If we're able to demonstrate, through additional research, that FMT is effective in treating diseases beyond C. diff, patients will have more treatment options available to them to help improve their quality of life.

I know the health care community shares in my excitement for this potential, which we saw firsthand during the microbiome-themed Twitter chat hosted by DDW earlier this week. The buzz around the microbiome demonstrates that we have only begun to truly understand the microbiome and how we might be able to leverage it in the development and treatment of not just digestive diseases but also of cardiovascular disease, autoimmune and metabolic disorders.