Ulcerative colitis (UC) is a chronic condition that leads to inflammation in the digestive tract. Researchers have linked decreased gut microbiota diversity to gastrointestinal diseases, such as UC.

A man sat on a bed in a consultation room and talking with a health professionalShare on Pinterest
Thomas Barwick/Getty Images

In this Behind the Counter, Dr. Youssef (Joe) Soliman, Clinical Assistant Professor at City of Hope Cancer Treatment Center in Phoenix, explains what a fecal transplant is and what the current research says about the efficacy of this procedure for treating ulcerative colitis (UC).

A fecal transplant involves collecting stool specimens from one or more individuals and “transplanting” them into another person’s gut. The aim is to recreate a diverse microbiota environment consisting of bacteria and other gut organisms from healthy donors.

The procedure uses various methods of transplantation. One technique involves creating a liquid slurry from donor stools and passing it through a nasoduodenal tube — a tube that enters the nose and goes down into the small intestine, bypassing the stomach — or, more commonly, using a colonoscopy.

As stool contains microorganisms, the potential transmission of infections is a concern. Most centers that offer fecal transplants have some sort of protocol to screen donor stools for a set list of infections. The genetics, health, and lifestyle of stool donors may also affect how fecal transplant recipients respond to the procedure.

Other than this, fecal transplants via nasoduodenal tube or colonoscopy carry only the same risks as the placement of a nasoduodenal tube or a colonoscopy.

Most short-term side effects are gastrointestinal in nature and can include:

Serious side effects are not common but may include severe infection, toxic megacolon, and colon perforation. There are also rare reports of the procedure being fatal.

The use of fecal transplants as a treatment for UC is an area of active research, with some studies reporting efficacy in inducing or maintaining remission in people with this condition who have undergone multiple treatment sessions.

However, the individuals who have participated in studies so far have been relatively young and had milder disease forms. They have also been on stable dosages of standard medications.

While fecal transplants show promise as a successful treatment for UC, it is unclear whether they can cure the condition or work as a stand-alone treatment.

Fecal transplant is currently not a standard treatment for UC. Most people who undergo a fecal transplant for UC do so as part of a research study.

However, clinical practice guidelines on how to treat a recurrent Clostridium difficile infection (CDI) do include fecal transplant as a treatment option for CDI that does not respond to first- and second-line therapies. Therefore, if recurrent and persistent CDI complicates a person’s UC treatment, they may be a candidate for fecal transplant to treat the CDI.

Before a person undergoes a fecal transplant, their healthcare team will likely recommend that they use a bowel prep to mobilize the stool and try to empty the colon.

Post-fecal transplant protocols usually include an antidiarrheal regimen to allow for the uptake of the transplanted microbiota into the recipient’s colon.

There are no specific foods to avoid after a fecal transplant. However, the general advice for people with UC is to eat a nutritious, well-balanced diet and minimize pro-inflammatory foods. These foods include animal and milk fats, protein, polyunsaturated fatty acids, and refined sugars.

Some examples of suitable diets to follow include:

To date, researchers have studied fecal transplant in individuals who are younger, have relatively mild disease forms, and are already on stable dosages of medications.

Some unanswered questions that researchers are actively studying include:

  • What is the optimal administration route?
  • Can healthcare professionals reliably use fecal transplants without other treatments?
  • How practical and sustainable is each treatment session?

Researchers theorize that the pathogenesis of UC is multifactorial, meaning that multiple factors contribute to the initiation and propagation of inflammation.

People with UC have an altered gut microbiota compared with controls. However, it is not entirely clear whether these changes are a cause or an effect of the disease.

Researchers continue to have an active interest in studying and regulating the gut microbiota in people with UC. Treatments such as fecal transplant may, one day, supplement other treatment strategies in controlling diseases such as UC.