But faecal transplants have hardly become common practice. The procedure faces regulatory hurdles since it doesn't involve a typical drug or device. By its nature, it is very hard to standardise and test through randomised clinical trials -- the gold standard of medicine. There are concerns about spreading new diseases along with the helpful bacteria. The stool needs to be freshly collected and used within several hours. And, understandably, there's the "ick factor" (for that reason, many people prefer that the donor be a spouse or relative).
To circumvent these obstacles, Elaine Petrof and Gregory Gloor from Kingston General Hospital in Ontario have developed a pseudo-poo -- a blend of 33 different gut bacteria that mimics the community found in a healthy gut. This "stool substitute" can be cooked up again and again according to the same recipe, and infused into patients without any of the extra faecal matter that makes such transplants so viscerally off-putting or potentially dangerous. Think of it as a rectally applied yoghurt. [...]
Petrof and Gloor based their substitute on the gut bacteria of a healthy 41-year-old woman. They isolated 62 species from her bowels and excluded any that showed even mild signs of antibiotic resistance -- those aren't microbes you want to be deliberately applying to someone's gut. Thirty-three species remained, which Petrof and Gloor balanced according to their typical proportions in a healthy gut.
The result is a standardised bacterial broth that's clear of any other disease-causing microbes or viruses, and that can be applied as an enema. (I can go for years without reading the words "drizzled throughout the transverse colon as the colonoscope was withdrawn" in a paper again.)
Current Music: Battle of Mice -- Cave of Spleen ♬