Superiority of Higher-Volume Fresh Feces Compared to Lower-Volume Frozen Feces in Fecal Microbiota Transplantation for Recurrent Clostridioides Difficile Colitis.

Goals: To compare the clinical outcomes of different protocols for fecal microbiota transplantation (FMT) in two community hospitals with similar patient demographics.
Background: FMT is commonly performed for recurrent or refractory Clostridioides difficile infection (rCDI). The clinical efficacy of FMT for this indication has been well established. However, there has been no standardization or optimization of the amount of fecal material, method of feces preparation, or route of delivery for FMT.
Study: In this retrospective study, patients with rCDI received FMT using commercially available frozen fecal preparation (22.7 g) at Center A and locally prepared fresh fecal filtrate (30-50 g) at Center B. The primary outcome was defined as complete resolution of clinical symptoms related to rCDI after at least 8 weeks of follow-up.
Results: Fifty patients from each center were included in the study. Clinical success after initial FMT with lower-volume frozen fecal preparation at Center A was 32/50 (64.0%) compared to 49/50 (98.0%) with higher-volume fresh fecal filtrate at Center B (p < 0.0001). Seventeen patients in Center A and 1 patient in Center B underwent at least one repeat FMT. Overall clinical success was achieved in 43/50 (86%) of patients in Center A and 50/50 (100%) in Center B (p = 0.012).
Conclusions: Our results suggest superior clinical efficacy of a larger amount of fresh fecal filtrate over a smaller amount of commercially available frozen fecal preparation. Further studies are needed to examine the effect of varying amounts of feces and the optimal protocol for FMT in patients with rCDI.