Fecal Transplant Provides Relief From Irritable Bowel Syndrome Symptoms, Study Finds

Fecal transplant — when stool with healthy microorganisms is inserted into a person’s digestive tract — has been shown to reduce abdominal stress and tiredness in patients with irritable bowel syndrome (IBS). Recent research published in the journal Gastroenterology found that these positive effects may last up to three years or even longer.

“A single fecal microbiota transplant [FMT] done with the proper protocol improved IBS symptoms, chronic fatigue [which coexists with IBS], and quality of life in about 90 percent of IBS patients after three months, with over 70 percent of the patients maintaining these improvements after three years,” says lead study author Magdy El-Salhy, MD, a gastroenterologist at Stord Helse Fonna Hospital in Norway. “This makes FMT an effective, easy-to-perform, and cheap treatment for IBS.”

For the study, Dr. El-Salhy and his colleagues followed 125 patients diagnosed with IBS: 104 women and 21 men. Doctors administered 30 grams (g) of feces with a healthy mix of microbes to the duodenum (the first part of the small intestine) of 42 patients. Another 45 received 60 g, while 38 were placed in a placebo group (not receiving any FMT). Patients provided a fecal sample and completed five questionnaires at the start of the study and at two and three years after receiving the transplant.

After three years, some patients dropped out, leaving 37 in the 30 g group, 39 in the 60 g group, and 37 in the placebo group.

When measuring the percentage of participants who responded positively to treatment, researchers calculated response rates two years after FMT to be 26.3 percent, 69.1 percent, and 77.8 percent, in the placebo, the 30 g group, and the 60 g group, respectively. At three years, the response rates were 27 percent, 64.9 percent, and 71.8 percent.

The research team also noted that dysbiosis — an imbalance in the microbiota in the gut — was lower only in the active treatment groups at two and three years after the fecal transplant.

Purna Kashyap, MBBS, a specialist in gastrointestinal disorders and codirector of the Microbiome Program at the Mayo Clinic in Rochester, Minnesota, finds the results to be reassuring but warned more research is needed.

“An important thing to keep in mind is that the study found a decrease in severity of symptoms, but there was no significant difference among the groups in terms of complete resolution of symptoms,” says Dr. Kashyap, who was not involved in the study. “While this study shows benefit from FMT and is definitely something to be optimistic about, it is also important to keep in mind that there are other studies which do not show improvement, hence we should not jump the gun and start advocating FMT in IBS patients until we see results from larger multicenter trials.”

Apart from mild side effects such as intermittent abdominal pain, diarrhea, and constipation reported within the first two days after the fecal transplant, no long-term effects were observed.

In addition to demonstrating improvement from FMT, the study found 10 intestinal bacteria in participant fecal samples that are related to both IBS symptoms and fatigue. Eight of the bacteria were linked to a positive effect, while two were associated with a negative effect.

“These identified intestinal bacteria that may lie behind IBS and fatigue can be used in the near future in treating IBS,” says El-Salhy. “Probably a culture of beneficial bacteria can be given in capsule form to release these bacteria into the small intestine. This is something that lies in the near future.”

El-Salhy also pointed out that the transplant was administered into the small intestine, which he suspects results in long-term colonization of beneficial bacteria, whereas administrating the transplant into the large intestine (colon) results in short-term colonization of these bacteria.

“We believe that the protocol we used is a step forward in constructing a standard FMT protocol for IBS treatment,” he says. “Furthermore, it could be tested in other gastrointestinal and non-gastrointestinal diseases, where the outcome of FMT varied with the protocol used.”

The International Foundation for Gastrointestinal Disorders estimates that about 5 to 10 percent of the world’s population has irritable bowel syndrome. About 60 to 65 percent of those who report having IBS are female. The condition is characterized by abdominal pain or discomfort, and chronic or recurrent diarrhea, constipation, or both.

While there is no cure for IBS, the Cleveland Clinic says that symptoms may be managed through diet, lifestyle changes, reducing stress, and counseling. In some cases, antidepressants and medication that relieves diarrhea, constipation, or abdominal pain may help.

At this time, FMT is not approved by the Food and Drug Administration (FDA) for IBS or other diseases, and further research is required before that may become the case. The federal agency only allows its use as an investigational new drug to treat Clostridium difficile (C. difficile or C. diff, for short) infection not responding to standard therapies. C. diff is a germ (bacteria) that causes diarrhea and colitis (an inflammation of the colon). The FDA has also warned that the use of FMT comes with the potential risk of serious infection due to the possible transmission of multidrug-resistant organisms. In 2020, two patients who received FMT died.

Still, because the composition of bacteria in the gut microbiome is considered to play such a pivotal role in this disorder, El-Salhy sees fecal transplant as a promising treatment for IBS and chronic fatigue in the future.

“A revolutionary approach to treating IBS is on its way in the near future with [fecal matter] donor banks and probably a single capsule containing the intestinal beneficial bacteria as medication,” predicts El-Salhy.

Kashyap, who is also a spokesperson for the American Gastroenterological Association, adds that overall the study provides optimism for the use of therapies targeting the microbiome but “there is much work yet to be done.”