Examining clinical similarities between myalgic encephalomyelitis/chronic fatigue syndrome and D-lactic acidosis: a systematic review.
Wallis, Amy, Ball, Michelle, McKechnie, Sandra et al. · Journal of translational medicine · 2017 · DOI
Quick Summary
This study compared symptoms reported in cases of D-lactic acidosis (a rare condition where a specific type of acid builds up in the body) with symptoms of ME/CFS. Researchers found that many neurological symptoms—like brain fog, movement problems, and nerve-related issues—appeared in both conditions. Both groups also had gut bacteria imbalances and stomach problems. The authors suggest that ME/CFS might involve similar gut-related processes as D-lactic acidosis, but stress that we need more research to understand if this connection is real.
Why It Matters
This study opens a novel research direction by suggesting ME/CFS and D-lactic acidosis may share biological mechanisms involving gut bacteria and lactate production. If this connection is validated, it could lead to new diagnostic tests (measuring D-lactate levels) and potentially new treatment approaches targeting gut bacteria and acid metabolism in ME/CFS patients.
Observed Findings
Majority of neurological disturbances in D-lactic acidosis case reports overlapped with ME/CFS diagnostic criteria
Motor disturbances were the most frequently reported D-la symptoms and appeared more prominent in severe ME/CFS presentations
Both patient groups shared histories of gastrointestinal abnormalities and bacterial dysbiosis
Only preliminary evidence supported the role of lactate-producing bacteria in ME/CFS
Inferred Conclusions
ME/CFS and acute D-lactic acidosis may represent points on a continuum related to D-lactate absorption
Microbiota-gut-brain interactions involving lactate-producing bacteria may be relevant to ME/CFS pathophysiology
Direct measurement of D-lactate levels in ME/CFS patients is needed to evaluate whether subclinical D-lactate affects neurological symptoms
Remaining Questions
Do ME/CFS patients actually have elevated or abnormal D-lactate levels, and if so, do these correlate with symptom severity?
Which specific lactate-producing bacteria strains are involved in ME/CFS, and how do they cause symptom manifestation?
What mechanisms explain why D-lactic acidosis presents acutely while ME/CFS is chronic—are different factors at play?
What This Study Does Not Prove
This study does not prove that D-lactate causes ME/CFS or that measuring D-lactate will be clinically useful—it only identifies symptom similarities and raises a hypothesis for future testing. The finding that symptoms overlap does not establish that the underlying causes are the same, as different mechanisms could produce similar neurological effects. No D-lactate measurements were actually performed in ME/CFS patients in this review.