Researchers say they have verified the effectiveness of a quicker way to rid people of recurring C. difficile bacterial infection.
A new clinical trial has shown that frozen stool samples work just as well as freshly donated samples when treating a tough C. difficile infection through a procedure called fecal transplantation.
Doctors have used frozen stool samples to treat C. difficile for a couple of years, because the prepackaged samples allow for much easier and swifter treatment than identifying and screening a fresh donor, said lead author Dr. Christine Lee, director of the microbiology residency program at McMaster University in Ontario, Canada.
“Donor screening can take one to two weeks,” Lee said. “If a person requires fecal transplant right away, then that’s not possible.”
The clinical trial showed that patients do not pay a price for the convenience that comes with using frozen stool samples. “Frozen samples were not inferior to fresh samples. It was equivalent,” Lee said.
The trial’s findings are published Jan. 12 in the Journal of the American Medical Association.
Clostridium difficile, or C. difficile, is an opportunistic bacteria that can invade the intestines of people whose gut bacteria have been wiped out by heavy doses of antibiotics. Left untreated, it often causes life-threatening bouts of diarrhea, according to the U.S. National Institutes of Health.
Patients can struggle with C. difficile for a long time because it becomes part of their gut’s microbiology. More than three out of every five people with the infection experience repeated episodes of diarrhea as they battle the bacteria, according to background notes with the study.
Fecal transplantation is emerging as the standard of care for people with recurrent C. difficile, said Dr. Colleen Kelly, an assistant professor of gastroenterology with the Women’s Medicine Collaborative at Brown University’s Warren Alpert Medical School in Providence, R.I.
As many as nine out of 10 patients with persistent C. difficile are cured through fecal transplantation, in which the stool of a healthy donor is introduced into a person’s gut through an enema or a colonoscopy, Kelly said.
But finding a donor isn’t simple. Potential donors must be screened for infectious diseases like HIV or hepatitis, as well as intestinal parasites and other bugs, Lee and Kelly said. These screenings require time that a patient with dire health problems might not have.
To solve this problem, a couple of U.S.-based companies have emerged that prepare and ship frozen stool samples from pre-screened donors, Lee and Kelly said.
“Being able to use frozen has really expanded fecal transplantation to a greater number of patients,” Kelly said.
Noting that she was scheduled to perform a fecal transplant in about an hour, Kelly described how she uses a frozen sample.
“I have a freezer with little bottles of frozen stool,” Kelly said. “They thaw out in the refrigerator overnight or at room temperature in a couple of hours. I swung by the lab last night and picked up a dose because I knew I was going to be doing one this morning, stuck it in the refrigerator and now it’s ready to go.”
In the clinical trial, Lee and her colleagues randomly assigned 232 C. difficile patients to receive either a frozen or fresh fecal transplantation via enema.
They found that frozen samples cured 83.5 percent of patients within 13 weeks, compared with about 85 percent of patients treated with fresh samples.
Further, they found no serious side effects with either fresh or frozen fecal transplantation.
“People have wondered, you’re putting all these germs in somebody, can you transmit an infection or something else,” Kelly said. “They’ve shown that in the short-term, anyway, fecal transplantation appears safe. We definitely need more long-term data, though, and apparently the authors plan on following these patients for 10 years.”
Kelly thought the researchers’ use of enemas to implant the stool samples was an interesting alternative to colonoscopy, the procedure her center uses for fecal transplants.
“Anybody can do an enema,” she said. “You don’t have to be a gastroenterologist with special training. A nurse can administer an enema. That really makes it easier, and brings the cost way down.”
However, Lee warned this is one medical procedure that patients shouldn’t attempt on their own.
“You don’t want to accidentally acquire hepatitis or HIV by a stool sample from a donor who hasn’t been properly screened,” Lee said.
For more on C. difficile, visit the American Academy of Family Physicians.