Modulation of Clostridium difficile induced mortality as a function of the dose and the viability of the Saccharomyces boulardii used as a preventative agent in gnotobiotic mice.

The ability of viable and nonviable Saccharomyces boulardii to protect gnotobiotic mice from Clostridium difficile induced mortality was tested. With the exception of irradiated S. boulardii, which retained some activity, only viable yeast protected the mice from lethality. The survival of C. difficile infected mice was dependent on the dose of the yeast provided in the drinking water.