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Are Fecal Transplants the Answer to Devastating Diarrhea?

In recent years, studies have shown that an overuse of antibiotics can trigger an imbalance of bacteria in the gut and result in the rise of severe infections of the colon.

We talked to UNC REX gastroenterologist Tanvir Haque, MD, to learn how fecal microbiota transplant—taking stool from a healthy donor and putting it into the colon of the ailing person—may be the answer to treating this potentially life-threatening infection.

How C. Diff Takes Over

Many people already have clostridium difficile, or C. diff, in their guts. It is thought to be a “bad bacteria” in the colon that can cause deadly diarrhea. However, we usually have enough “good bacteria” to keep this bad bacteria in check, so we don’t experience any problems.

“When you have an event such as an infection or take a course of antibiotics that wipe out all that good gut bacteria, that opens the door for C. diff to take over and run rampant in your colon,” Dr. Haque says. “And that’s when you get symptoms of C. diff colitis.”

Colitis means inflammation of the colon. Symptoms include watery diarrhea several times a day, fevers, severe stomach cramps and nausea. C. diff colitis is colitis caused by the C. diff bacteria. Colitis also can be caused by inflammatory bowel disease, infections, allergic reactions and microscopic colitis.

Antibiotics: The First Line of Defense

Dr. Haque says two weeks of antibiotics is usually first prescribed to treat C. diff.

“The idea is to kill off the bad bacteria and give the good bacteria a chance to regenerate, which restores balance in the colon,” he says.

This works for many patients; however, some respond well to the antibiotics and then relapse soon after they finish taking them. For these patients, the next step is a “pulse taper.”

“We taper this next course of antibiotics over four to six weeks, where you get an antibiotic twice a day, then every other day, then every third day and so on,” Dr. Haque says. “The idea is to extend the duration of antibiotics over several weeks, so we’re slowly eliminating the C. diff over time.”

This treatment strategy works for the majority of patients, but about 25 percent relapse after they finish the pulse taper antibiotics.

“When it recurs after they’ve finished this course of antibiotics, they may be a candidate for a fecal transplant,” Dr. Haque says.

Before Fecal Transplant, a Colonoscopy

Before proceeding with a fecal transplant, a gastroenterologist will need to confirm C. diff is causing the symptoms.

“When someone is diagnosed with C. diff and their diarrhea continues despite being on antibiotics, there could be something else going on, such as another type of infection, inflammatory bowel disease or irritable bowel syndrome, which also can cause diarrhea,” Dr. Haque says.

This is determined with a colonoscopy.

“The prep for the colonoscopy clears out the colon, so we get a good sense of how the colon looks and get the lay of the land,” Dr. Haque says. “And we can make sure there’s nothing else going on that can be causing the diarrhea before we proceed with the transplant.”

How a Fecal Transplant Works

During the colonoscopy, once a gastroenterologist rules out other causes, he or she will place about 250 milliliters of new stool—a little less than the size of a soda can—inside the colon. This amount is enough to fill up the colon with good bacteria.

In Dr. Haque’s practice, the new stool comes from a stool bank called OpenBiome, which provides healthy stool to hospitals and health care providers across the U.S.

“They identify donors who go through a very rigorous screening protocol to make sure they’ll be suitable donors. They make sure that these are very healthy individuals who haven’t been on any antibiotics recently and don’t have any major medical problems,” Dr. Haque says. “After they are approved to be donors, they have their stool tested regularly to make sure they haven’t had any changes in their health or been exposed to any infections.”

The procedure takes 10 to 15 minutes, and patients then are asked to hold the stool in as long as possible—usually about an hour—which most are able to do. Dr. Haque says the first few bowel movements after the procedure may be a little irregular, but patients generally begin to feel relief from their original symptoms in 48 to 72 hours.

“The diarrhea that they were experiencing, which for some was for months, generally goes away. The abdominal pain and nausea also go away,” Dr. Haque says. “They feel better about two to three days after the procedure. And then about a week after the procedure, they usually feel back to normal.”

The cure rates are 80 to 90 percent after a fecal transplant, Dr. Haque says.

“We’re not necessarily going to eradicate the C. diff, but you give the patient this ‘super probiotic’ and just overwhelm the C. diff with good bacteria. It is now again able to do its job and keep the bad bacteria under control,” he says. “You restore that balance and go back to living your normal life.”

Taking Care with Antibiotic Use

C. diff is more common today than in the past because antibiotics are used more often. Although people need to be on antibiotics for serious infections, sometimes it is better to avoid them in milder cases.

“I don’t think it’s necessarily wise to take antibiotics just for a sore throat, a cough or for any dental procedure. If you’re told you need an antibiotic, think about the trade-off,” Dr. Haque says. “You trade maybe some mild symptom improvement but increase that risk getting a severe infection of your colon that can result in some significant quality-of-life issues, loss of work, the need for medicine or antibiotics, and maybe even a transplant down the road.”


If you’re struggling with digestive problems, talk to your doctor or find a gastroenterologist near you.