Antibiotic-associated diarrhea (AAD) refers to the occurrence of other unexplained diarrhea symptoms after the use of antibiotics, often combined with abdominal pain, bloating and bloody stool. Fecal Microbiota Transplantation (FMT) is a therapeutic method to transplant the microbiota from the feces of healthy people into the intestinal tract of patients. To explore the overall efficacy and safety of FMT in the treatment of AAD.

Inclusion Criteria:

• occurrence of antibiotic-associated diarrhoea; no response to standard therapy; agree to receive FMT and sign informed consent; willingness to provide stool samples.

Exclusion Criteria:

• non-antibiotic-associated diarrhea; did not accept FMT or did not sign informed consent; unwillingness to provide stool samples.