Gough et al. recently reviewed the efficacy of intestinal microbiota
transplantation (fecal bacteriotherapy) for RCDI, and reported
an overall cure rate of 92% [20]. Characteristics that were associated
with lower rates of resolution of diarrhea included single stool
sample instillation and instillation via the upper intestinal tract as
opposed to instillation into the lower intestinal tract using retention
enema kits or the colonoscope. In the current case series, 59 of 75
FMTcourses resulted in clinical resolution of recurrent diarrhea, for
a primary cure rate of 79%, which is essentially identical to the cure
rate reported in Gough’s review (77% when stool was administered
to patients via gastroscope or nasojejunal tube). When FMT is
provided through the lower GI tract (via a colonoscope or fecal
enema kit) the observed cure rates are higher and range between 92
and 98% [20,22]. Thus, the instillation route of FMT is important, not
only because of different success rates associated with different
routes of administration, but also because patient or provider
preferences may influence choice of routes of administration. The
explanation for the reported lower cure rates associated with FMT
administered via the upper gastrointestinal tract is not well
understood, but may simply be related to the lower volume of stool
mixture that has been used with the upper GI instillation procedure.
Additional research is needed on both the route of administration of
FMT and on the volume of stool mixture used.