The procedure is not recent, but the first description of this technique dates from 1958. The principle is simple: it consists of attempting to replace the unbalanced gut flora of a patient with colitis—the latter induced by antibiotic treatment for IBD--by the gut flora of a healthy donor. Gut transplantation, a technique that was long considered scatterbrained or even dangerous, is now taken seriously in treatment of colitis following antibiotic treatment for Clostridium difficile. These types of colitis are often severe if relapse occurs in the elderly or in fragile subjects. In this situation, fecal transplantation has given nearly 100% favorable results in open series over the short and long term, and has become the reference treatment, although control trials are now in progress that should enable reaching a definitive conclusion.

In practice, fecal matter from a healthy donor (often a family member), after eliminating infectious agents, is mixed with saline solution, filtered and then introduced using a nasogastric probe, either during coloscopy or enema. The mechanism of action of the transplantation is under study, but certain works suggest that transplantation enables at least the temporary restoring of the balance of the flora while at the same time eliminating pathogenic agents.

Borody's team (Center for the Study of Digestive Diseases, Five Dock, Australia), one of the pioneering teams for this technique, has demonstrated that bacteria from fecal matter of the donor remain in the recipient's body up to 24 h after injection.

A number of studies on different pathologies are now in progress and are examining the efficacy and tolerance of this alternative therapy, which is both ecological and economic!