Systematic review with meta-analysis: effects of probiotic fungi on irritable bowel syndrome

Treatment of irritable bowel syndrome (IBS) remains challenging for clinicians. Probiotic fungi may act as candidate options for IBS treatment, but systematic evaluation of their clinical value remains scarce. This study is aimed to assess the efficacy and the safety of probiotic fungi for IBS treatment by means of systematic review and meta-analysis. PubMed, Embase, Web of Science, and the Cochrane Library, were searched up to June 2022. Randomised controlled trials recruited subjects with prescriptions of probiotic fungi were eligible. Efficacy and safety of probiotic fungi were re-evaluated. Continuous data were pooled to obtain standardised difference in means (SMD) with a 95% confidence interval. The search strategy identified 120 articles of which 7 trial assessing 883 subjects were included in the analysis. Systematic data support that Saccharomyces helps to relieve abdominal pain/discomfort (SMD = -0.205, P = 0.005), and presented potential improvements on psychological outcomes, stool form for IBS patients. It is hard to demonstrate favourable effects on other symptoms (including distension, mucus passage, sense of incomplete evacuation, urgency, straining). The incidence of mild complications ranged from 0 to 51.4%, but no serious complications were observed in the included trials. Therefore, the partial response and the relative safe of probiotic fungi for IBS treatment have been demonstrated from the existing trials. However, it is premature to eventually declare the practical effects of probiotic fungi. Conducting more high-quality and large-scale trials and real-world studies, or even developing new fungal strains, is still necessary.