Fecal microbiota transplantation: Review and update.

Fecal microbiota transplantation (FMT) is a method to directly change the recipient's gut microbiota to normalize the composition and gain a therapeutic benefit. The history of FMT has been traced back to the 4th century and has been highly regarded since 2013, when the United States Food and Drug Administration approved FMT for treating recurrent and refractory Clostridium difficile infection. Since then, the range of FMT applications extended rapidly and broadly not only in gastrointestinal disorders, but also in extra-gastrointestinal diseases. Donor selection with questionnaire, interview, blood tests, and stool examinations should be strictly performed before FMT to reduce and prevent occurrence of any adverse events. Step-by-step cautious fecal and recipient preparation along with adequately choosing delivery methods based on individual clinical situations are key points of the FMT process. Although current evidence deems FMT as a generally safe therapeutic method with few adverse effects, the long-term outcomes of FMT have not been completely elucidated. Therefore, establishing periodicity and length of regular follow-up after FMT to monitor the clinical efficacy and long-term adverse events are other essential issues. In the future, we will look forward to personalized FMT for different patients and conditions according to varied hosts and diseases.