Fecal Microbiota Transplantation: The Evolving Risk Landscape.

Fecal microbiota transplantation (FMT) has been recommended in clinical guidelines for the treatment of recurrent Clostridioides difficile infection (CDI). However, it is considered investigational by most regulatory agencies. As the adoption of FMT has increased from a small group of CDI experts alone to more widespread use, there has been a corresponding increase in concern regarding potential risk. FMT is largely considered a safe procedure although risks described range from mild gastrointestinal symptoms to serious infection. Currently, there is variability in how "FMT" is characterized specifically regarding testing approach, which, in turn, impacts the risk profile. This has been highlighted by the rare cases of multidrug-resistant organisms, Shiga toxin-producing Escherichia and enteropathogenic E. coli, recently reported, where these organisms were not screened. These cases have prompted additional screening mandates from the US Food and Drug Administration (FDA), which has maintained its policy of enforcement discretion for the use of FMT for CDI not responding to standard therapy. Here, we examine the evolving risk landscape of FMT.