Fecal microbiota transplants, or FMT, is a relatively new procedure in which feces from a healthy donor is transplanted into the bowels of a sick patient. This is done to restore the sick patient’s microbiome, or the bacteria and other organisms that live in the intestines, to a healthy state.
The most common use for FMT is to combat the deadly bacterial infection Clostridium difficile (c. diff), which is often resistant to antibiotics. However, researchers are exploring how the gut’s microbiome affects a variety of conditions.
FMT is not yet approved by the FDA, but it has become relatively standardized as a treatment for c. diff. Therefore, it came as quite a shock when a patient died at Massachusetts General Hospital after an FMT procedure. Another got seriously ill.
In an unusual show of transparency, the doctors in charge of FMT at Massachusetts General Hospital published a paper in the New England Journal of Medicine detailing exactly what went wrong.
A change in protocol wasn’t made retroactive
The FDA does have protocols for FMT procedures and, in January, those protocols were updated. The agency increased screening for certain emergent organisms, including a drug-resistant version of E. coli. However, the FDA did not make clear that the new screening should be performed on feces that was already in storage waiting for transplantation.
“It wasn’t obvious to a lot of smart people here,” the journal articles lead author told the New York Times. “We didn’t think to go back in time.”
Unfortunately, the hospital did not test the stored feces for the newly emerging organisms, and the two patients were exposed to bacteria-resistant E. coli. That bacterium can be harmless in a healthy person, so the donor probably didn’t even know they had it. Drug-resistant E. coli, however, can wreak havoc on someone with a compromised immune system, including many people receiving fecal transplants.
The two patients who received the contaminated feces were a man with end-stage liver disease and a man with a rare blood cancer. The man with cancer was immunocompromised, and he died from a severe bloodstream infection about ten days after is last FMT dose.
According to the Times, Massachusetts General is unusual in that it produces its own FMT material, most fecal transplant material in the U.S. comes from a single nonprofit called OpenBiome. The company says it began testing donors for drug-resistant E. coli in 2016. It has provided some 50,000 FMT doses over the past few years with no reported adverse events.
Next week, the FDA will hold hearings on the risks and benefits of FMT. In the meantime, it only allows FMT in patients who do not respond to standard therapies.