1. As subjects must meet standard clinical criteria for candidacy for FMT, all patients will have suffered symptomatic diarrhea and have documented stool c. difficile toxin positivity. Almost all patients will have failed standard therapy for CDI, which includes at least one course of treatment with a primary agent (metronidazole, vancomycin or fidaxomicin), as well as an extended vancomycin taper following either the second or third recurrence. There may be extenuating circumstances that could justify FMT for CDI outside of these parameters, such as severe allergy to multiple of the above agents, though this would be expected to be exceedingly rare.