Some types have been linked to diseases including cancer, obesity and diabetes – and there is no way to be sure the recipient of FMT isn’t increasing their risk of these disorders, says Allen-Vercoe.“We shouldn’t blithely be doing faecal transplants wherever we can just because we think it’s a good idea,” she says.“The blood and pain are reduced, and I’m not having to worry about going to the toilet.” Jim is one of a growing number of people turning to faecal microbiota transplantation (FMT) to restore their gut bacteria to a healthy state.The idea is to reset the gut flora using bacteria in the stools of a healthy person.“They’re putting themselves at significant risk.” Last week, a group of microbiologists writing in Nature called for the US Food and Drug Administration to change the rules on FMT, and for regulators around the world to work out how to deal with the procedure. And is it worrying that people are doing it themselves?The technique has shown most promise for treating people infected with Clostridium difficile, a bacterium that colonises people’s gut when antibiotics have obliterated the other inhabitants, sometimes to fatal effect.As a result, the FDA considers FMT as an investigational drug for everything apart from treatment of non-responsive C. This means doctors have to apply for a licence to use the treatment as part of a study. “It takes hundreds of hours to open an application and many more are spent monitoring patients,” says Mark Smith at the Massachusetts Institute of Technology.This means people are doing their own transplants at home, using little more than stools from a relative, a blender and an enema kit (see “From trash to treasure“).
difficile infections – so it is of no use to people trying FMT at home. “If a patient is dead set on getting treatment, it’s probably a good idea to have a doctor help.” Writing in Nature on 19 February, Smith and two colleagues called on the FDA to regulate faecal transplants in the same way as tissue transplants of blood, bone and cartilage.The results of a clinical trial using FMT to treat people with recurring C.difficile infections, the first ever for any FMT treatment, were published last year.“People are turning to faecal transplants without any medical supervision.They don’t even get the donor screened,” says Emma Allen-Vercoe, a microbiologist at the University of Guelph in Ontario, Canada.Some parents of children with severe autism, for example, are swapping notes on FMT on online forums, even though all they have to go on is limited evidence of an altered gut flora in autism, and a study that showed a species of bacteria could reverse some symptoms in mice with an autism-like disorder. Side effects have been rare so far, but there are reports of faecal transplants causing infection and gastrointestinal bleeding.