Pills fashioned from beneficial microbes in feces overcome C. difficile
SAN FRANCISCO — A hold-your-nose treatment in which doctors use human feces as a colonic transplant has taken a turn that skirts its obvious drawback: the “ick” factor of getting such an enema. By gleaning the healthy bacteria from feces and wrapping them in coated capsules, researchers have created an odorless treatment for intestinal infections that may be just as good as the poopy one.
Early results show that the capsules have cured 32 people infected with drug-resistant Clostridium difficile, a dangerous microbe that installs itself in the gut and causes inflammation marked by diarrhea, cramping and pain.Thomas Louie, an infectious disease physician at the University of Calgary in Alberta, presented the data on October 3 at ID Week, a meeting of infectious disease specialists. Louie’s research team used filtration to capture the good bacteria from feces, which in most cases came from a family member of the patient. The bacteria were then encapsulated with a coating so that they could pass through the stomach and reach the intestines.
“This is definitely more palatable for the patient,” said Thomas Moore, an infectious disease physician at the University of Kansas School of Medicine at Wichita who wasn’t part of the study. The process to make the capsules might pose some technical hurdles for broader use, he said. “But if that’s what it takes to overcome resistance to doing it, then by all means we should do it.”
C. difficile causes diarrhea that is linked to 14,000 deaths each year in the United States, according to the Centers for Disease Control and Prevention. It can strike when antibiotics wipe out beneficial bacteria residing in the gut. Their absence allows C. difficile to gain a foothold, reorder the intestines’ microbial mix and cause symptoms. Fecal transplants have been successful at reintroducing a normal bacterial blend that can crowd out C. difficile and have proved to be safe, Moore said.
Louie had been performing fecal transplants for years until 2009 when one of his C. difficile patients couldn’t retain the enema long enough for it to take effect. So he decided to create a capsule of bacteria, “getting rid of everything else” in the feces, he said. After his initial patient seemed cured of C. difficile, he expanded the operation. The current treatment requires a patient to take 24 to 34 capsules stocked with good bacteria in a single day, on an empty stomach.
He has followed the 32 C. difficile patients for various lengths of time, from a few months to three years; nearly all have had no recurrence of infection, even though each had had at least three bouts before treatment. One recent patient experienced a mild recurrence, after taking antibiotics for an unrelated infection. That suggests the antibiotics interfered with the reordered bacterial mix in the gut, Louie said. That patient may now be cured too, he said. He now tells patients to avoid antibiotics for six months to a year after the capsule treatment.
T. Louie et al. Fecal microbiome transplantation (FMT) via oral fecal microbial capsules for recurrent Clostridium difficile infections (rCDI). ID Week 2013, San Francisco, October 3, 2013.
T. Saey. Inside job. Science News. Vol. 179, June 18, 2011, p. 26.