Rifaximin alters gut microbiota profile, but does not affect systemic inflammation - a randomized controlled trial in...

Area of Science:

• Immunology
• Microbiology
• Gastroenterology

Background:

• Common Variable Immunodeficiency (CVID) is linked to reduced gut microbial diversity, gut leakage, and systemic inflammation.
• Gut dysbiosis, characterized by specific bacterial changes, is observed in CVID patients.
• Rifaximin, a non-absorbable antibiotic, is known to reduce gut leakage in other conditions.

Purpose of the Study:

• To investigate if altering gut microbial composition with rifaximin can reduce systemic inflammation in CVID patients.
• To assess the impact of rifaximin on gut leakage markers and microbial diversity in CVID.
• To evaluate rifaximin as a proof-of-concept intervention for CVID-related inflammation.

Main Methods:

• A randomized, open-label, single-centre study involving 40 adult CVID patients.
• Patients received either oral rifaximin (550 mg twice daily) or no treatment for 2 weeks.
• Primary endpoints included changes in plasma/serum inflammatory markers and gut leakage indicators at 0, 2, and 8 weeks. Secondary endpoint was changes in gut bacterial diversity.

Main Results:

• Rifaximin treatment did not significantly alter systemic inflammation or gut leakage markers in CVID patients.
• A significant decrease in gut microbial diversity was observed in the rifaximin group compared to the control group (p=0.002).
• Key bacteria associated with CVID dysbiosis were not affected by rifaximin treatment.

Conclusions:

• Modulating gut microbiota with rifaximin does not appear to be an effective strategy for reducing systemic inflammation in CVID.
• Further research is needed to identify appropriate interventions for gut dysbiosis and associated inflammation in CVID.