Chronic fatigue syndrome patients have alterations in their oral microbiome composition and function.
Wang, Taiwu, Yu, Lei, Xu, Cong et al. · PloS one · 2018 · DOI
Quick Summary
Researchers studied the bacteria living in the mouths of ME/CFS patients and compared them to healthy people. They found that ME/CFS patients have a different balance of oral bacteria, with some types being more common and others less common. These bacterial differences appear to affect how the body processes energy and amino acids, which could be relevant to understanding ME/CFS.
Why It Matters
This study provides evidence that ME/CFS involves alterations in the oral microbiome beyond the gut, suggesting host-microbe interactions may be broadly relevant to disease pathogenesis. Understanding these microbial changes could eventually lead to new diagnostic markers or microbiome-targeted treatments, and the focus on metabolic pathways (energy, amino acids) aligns with known ME/CFS cellular dysfunction.
Observed Findings
Oral microbiome composition differs significantly between CFS patients and healthy controls, even though overall bacterial diversity levels are similar.
CFS patients have higher relative abundance of Fusobacteria phylum.
The bacterial genera Leptotrichia, Prevotella, and Fusobacterium are enriched in CFS patients.
The bacterial genera Haemophilus, Veillonella, and Porphyromonas are depleted in CFS patients.
Altered oral bacteria in CFS are functionally associated with amino acid and energy metabolism pathways.
Inferred Conclusions
The oral microbiome composition is altered in CFS patients in ways that differ from healthy controls.
These compositional changes correlate with shifts in bacterial metabolic functions, particularly in energy and amino acid metabolism.
Oral microbiota alterations may contribute to CFS pathogenesis through metabolic dysfunction.
Remaining Questions
Do oral microbiome changes precede CFS symptom onset, or are they a consequence of illness?
How do oral microbiome alterations relate to known gut microbiome changes in ME/CFS, and are they part of a systemic dysbiosis?
What This Study Does Not Prove
This study does not prove that oral microbiome changes cause ME/CFS—it only shows association. The cross-sectional design cannot establish whether bacterial alterations are a cause, consequence, or bystander phenomenon in ME/CFS. Results are limited to a Chinese Han population and may not generalize to other ethnic groups.