Systematic review and meta-analysis of Saccharomyces boulardii in adult patients

Abstract

This article reviews the evidence for efficacy and safety of Saccharomyces boulardii (S. boulardii) for various disease indications in adults based on the peer-reviewed, randomized clinical trials and pre-clinical studies from the published medical literature (Medline, Clinical Trial websites and meeting abstracts) between 1976 and 2009. For meta-analysis, only randomized, blinded controlled trials unrestricted by language were included. Pre-clinical studies, volunteer studies and uncontrolled studies were excluded from the review of efficacy and meta-analysis, but included in the systematic review. Of 31 randomized, placebo-controlled treatment arms in 27 trials (encompassing 5029 study patients), S. boulardii was found to be significantly efficacious and safe in 84% of those treatment arms. A meta-analysis found a significant therapeutic efficacy for S. boulardii in the prevention of antibiotic-associated diarrhea (AAD) (RR = 0.47, 95% CI: 0.35-0.63, P < 0.001). In adults, S. boulardii can be strongly recommended for the prevention of AAD and the traveler's diarrhea. Randomized trials also support the use of this yeast probiotic for prevention of enteral nutrition-related diarrhea and reduction of Helicobacter pylori treatment-related symptoms. S. boulardii shows promise for the prevention of C. difficile disease recurrences; treatment of irritable bowel syndrome, acute adult diarrhea, Crohn's disease, giardiasis, human immunodeficiency virus-related diarrhea; but more supporting evidence is recommended for these indications. The use of S. boulardii as a therapeutic probiotic is evidence-based for both efficacy and safety for several types of diarrhea.

Figure 1

Frequency of peer-reviewed publications on Saccharomyces boulardii from 1976 to 2009.

Figure 2

Schematic of intestinal tract, illustrating the different potential mechanisms of action of Saccharomyces boulardii (Sb). On the left, effects of different pathogenic microbes are depicted. On the right, seven different protective effects of S. boulardii are depicted. Within the lumin of the intestine, S. boulardii may degrade toxins of pathogens, interfere with pathogenic adherence, modulate normal microbiota and preserve normal intestinal physiology. S. boulardii may also indirectly restore normal short chain fatty acid (SCFA) balance. S. boulardii may also increase secretory IgA (sIgA) levels or act as an immune regulator by influencing cytokine levels.

Figure 3

Forest plot of meta-analysis of ten randomized controlled trials measuring protective effect after treatment with S. boulardii or placebo for the prevention of antibiotic-associated diarrhea in adult patients. The x-axis depicts effect size, with black dot denoting the relative risk and the line indicating 95% CI, with the size of the grey box proportional to the study size. Relative risks to the left of RR = 1 denote study favored the probiotic, RR to the right denotes the study favors the placebo. Overall, pooled RR was 0.47 (0.35-0.63).