Efficacy and Safety Evaluation of Fecal Microbiota Transplantation in Irritable Bowel Syndrome

Inclusion Criteria: * Patients who fulfilled the Rome IV criteria for the diagnosis of IBS, aged 18-70 years; * Patients who have experienced failure of at least 3 conventional therapies for IBS; * Absence of red flags such as weight loss, hematochezia; Exclusion Criteria: * Pregnant, planning pregnancy or lactating; * Psychiatric disorder or unable to cooperate with treatment and follow-up visit; * Immunodeficiency or treatment with immune-modulating medication; * Use of probiotics within the previous 3 months or treatment with antibiotics within 1 month prior to study entry; * Having undergone any abdominal surgery, with the exception of appendectomy, cholecystectomy, caesarean section and hysterectomy; * Presence of uncontrolled diabetes, hypertension, thyroid disease or other systemic disease; * Presence of severe diseases related to heart, brain, kidney and lung or concomitant malignancies;