Roles of Gut Microbiota and Associated Metabolites in Clostridioides difficile Infection

Area of Science:

• Microbiome research
• Gut health and disease
• Infectious disease epidemiology

Background:

• Clostridioides difficile infection (CDI) is a significant healthcare-associated infection.
• Gut microbiota dysbiosis is a primary risk factor for CDI.
• The role of specific Proteobacteria taxa in CDI pathogenesis requires further elucidation.

Purpose of the Study:

• To investigate the causal relationships between gut microbial taxa, particularly Proteobacteria, and CDI.
• To identify specific microbial taxa and metabolites involved in the development of CDI.
• To explore potential novel therapeutic targets for CDI.

Main Methods:

• Utilized linkage disequilibrium score regression (LDSC) on a Dutch cohort (n=7,738) to assess genetic correlations between 207 gut microbes and CDI.
• Performed Mendelian randomization (MR) analyses to evaluate causal links between 31 Proteobacteria taxa and CDI.
• Conducted two-step MR to analyze mediation effects of 1,400 metabolites on the microbiota-CDI relationship.

Main Results:

• Bivariate LDSC identified significant correlations between four Proteobacteria populations (Pasteurellaceae, Haemophilus, Pasteurellales, H. parainfluenzae) and CDI.
• Two-step MR revealed that the Burkholderiales order causally influences CDI by reducing 3-hydroxylaurate levels (OR 0.896, p=0.047).
• 3-hydroxylaurate was identified as a significant mediator between gut microbiota and CDI.

Conclusions:

• Genetically predicted gut microbiota and metabolite levels are associated with CDI risk.
• Targeting the Burkholderiales order and modulating 3-hydroxylaurate levels show promise as novel antimicrobial strategies against CDI.