Incidence of Saccharomyces cerevisiae fungemia in hospitalised patients administered Saccharomyces boulardii probiotic

Mycoses. 2021 Dec;64(12):1521-1526. doi: 10.1111/myc.13375. Epub 2021 Oct 9.


Background: Bloodstream infection is an untoward effect of probiotic administration described by case reports and a cited reason to avoid using in the critically ill. The incidence rate of bloodstream infection in a population administered probiotics remains unknown.

Methods: A retrospective observational analysis of incident Saccharomyces cerevisiae fungemia in a population of hospitalised patients administered Saccharomyces boulardii for primary prevention of hospital-onset Clostridioides difficile infection. Adult patients admitted to an inpatient medical unit for 48-h or more between January 1, 2016 and December 31, 2019 are included. Facility medication administration records and microbiology records were evaluated for S boulardii probiotic administration and incidence of S cerevisiae positive blood cultures. Microbiologic identification methods were unable to distinguish S cerevisiae from S boulardii.

Results: Administration of S boulardii probiotic occurred in 16,404 of 46,729 patients analysed. S cerevisiae fungemia was identified in 18 probiotic recipients (0.11%). The observed incidence of fungemia attributable to S boulardii administration is 1.70 cases per 10,000 patient-days. Central-line days numbered 52,949 yielding an incidence of 0.26 cases of S cerevisiae per 1,000 central-line days. Intensive care unit admission was significantly associated with an increase in the risk of S cerevisiae (OR 6.55, CI 2.28-18.87), incidence rate of 0.47 cases per 1,000 patient-days.

Conclusion: The risk of bloodstream infection as a result of S boulardii probiotic use appears restricted to S boulardii recipients. The risk for probiotic-related bloodstream infection does not appear greater than the risk of any hospital-acquired bloodstream infection both inside and outside of the intensive care unit.

Keywords: bloodstream infection; clostridium infections; fungemia; healthcare associated infections; probiotics; saccharomyces.

MeSH terms

  • Adult
  • Cross Infection* / epidemiology
  • Cross Infection* / prevention & control
  • Fungemia* / epidemiology
  • Fungemia* / prevention & control
  • Humans
  • Incidence
  • Probiotics* / adverse effects
  • Retrospective Studies
  • Saccharomyces boulardii*
  • Saccharomyces cerevisiae / pathogenicity*