Impact of probiotic Saccharomyces boulardii on the gut microbiome composition in HIV-treated patients: A double-blind, randomised, placebo-controlled trialOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
This study investigated whether the probiotic Saccharomyces boulardii changes the composition of the gut microbiome in HIV-treated patients, and whether such changes explain the probiotic's previously observed benefits. The researchers used 16S rDNA gene amplification and parallel sequencing on faecal samples to characterize gut microbiome composition. This built on prior findings from the same double-blind, randomised, placebo-controlled trial showing that 12 weeks of Saccharomyces boulardii reduced markers of bacterial translocation and systemic inflammation compared to placebo.
Who was studied?
The cohort consisted of 44 HIV virologically suppressed patients enrolled in a double-blind, randomised, placebo-controlled trial. Half of these patients (n = 22) were immunologic non-responders to antiretroviral therapy, defined as having fewer than 270 CD4+ T cells per microliter despite long-term suppressed viral load. All 44 patients had faecal samples analyzed after being randomized to receive either the probiotic or placebo.
What were the most important findings?
The abstract text provided is truncated before the specific 16S rDNA microbiome results are described, so the direct compositional findings of this analysis cannot be reported here. What is established is the premise motivating the analysis: the same trial previously found that Saccharomyces boulardii significantly reduced plasma lipopolysaccharide-binding protein (a marker of bacterial translocation) and IL-6 (a marker of systemic inflammation) relative to placebo. The aim of the microbiome analysis was to determine whether a decrease in gut bacterial species linked to translocation and inflammation underlies this clinical benefit.
What are the greatest implications of this study?
If confirmed, a link between probiotic-driven shifts in gut microbiome composition and reduced bacterial translocation would support Saccharomyces boulardii as an adjunct strategy for HIV patients who show poor immune reconstitution despite viral suppression. This approach targets the gut microbiota as a driver of chronic inflammation rather than the virus itself, offering a complementary avenue alongside HAART. Because immunologic non-response contributes to poor clinical outcomes despite effective antiretroviral therapy, microbiome-targeted interventions could address a persistent unmet need in this patient population.