Efficacy of Donor-Recipient-Matched Faecal Microbiota Transplantation in Patients with IBS-D: A Single-Centre, Randomized, Double-Blind Placebo-Controlled Study

<b><i>Introduction:</i></b> The imbalance in gut microbiota is contributing to the development and progression of IBS. FMT can improve the gut microbiota, and donor-recipient-matched FMT can help develop individualized treatment plans according to different enterotypes. This study aimed to explore the efficacy of donor-recipient-matched FMT in IBS with predominant diarrhoea (IBS-D) and evaluate its effects on gut microbiota. <b><i>Methods:</i></b> Twenty-seven patients with IBS-D were randomly divided into donor-recipient-matched FMT group (group P), random-donor FMT group (group R), and placebo group (group B). All participants received corresponding FMT treatment after filling in IBS-S, IBS-QoL, GSRS, and HADS questionnaires and having their stool samples collected at 4, 8, and 12 weeks after treatment. The improvement in the symptoms and the changes in the bacterial flora were analysed for three groups. <b><i>Results:</i></b> The IBS-SSS, IBS-QoL, GSRS, and anxiety scores of group P were significantly lower after treatment (<i>p</i> &lt; 0.05). The IBS-QoL scores of group R were significantly lower after treatment (<i>p</i> &lt; 0.05). Beta diversity analysis showed that the gut microbiota of group P had an obvious trend of classification after treatment. Seven bacterial genera were related to the differences in the IBS-SSS scores before and after treatment. <b><i>Conclusion:</i></b> Donor-recipient-matched FMT significantly improved the clinical symptoms, quality of life, and anxiety scores of the patients with IBS-D than random-donor FMT.