List of abnormal findings in chronic fatigue syndrome and myalgic encephalomyelitis

Myalgic encephalomyelitis/chronic fatigue syndrome is a complex multi-system disease and biological abnormalities in patients have been found affecting multiple bodily systems. No single biomarker-based diagnostic test has been validated but patients have a range abnormal physical findings affecting multiple bodily systems. The CDC states that diagnosing ME/CFS relies on a physical and psychiatric assessment, observations, medical history, clinical interview, and results from a mix of blood and urine tests.

Brain

 * Progressive brain changes

Central nervous system

 * increased ventricular lactate
 * neuroinflammation
 * reduced grey and white matter
 * 2019, Evidence of widespread metabolite abnormalities in Myalgic encephalomyelitis/chronic fatigue syndrome: assessment with whole-brain magnetic resonance spectroscopy

Autonomic nervous system

 * Orthostatic intolerance

Muscular system

 * mitochondrial abnormalities found via muscle biopsy including: mitochondrial degeneration, deletions of mitochondrial DNA, the reduction of mitochondrial activity
 * Increased urinary creatine excretion during relapses
 * Increased creatine kinase (postviral fatigue syndrome)
 * Persistence of enteroviruses in muscle tissue
 * abnormalities of AMPK activation and glucose uptake in cultured skeletal muscle cells

Immune dysregulation

 * Natural killer cell function is reduced
 * Cytokine dysregulation
 * Elevated regulatory T cells
 * increased mast cell populations
 * elevated anti-cholinergic muscarinic, Β-adrenergic, phosphatidylinositol and serotonin

Chronic infection

 * Enterovirus: Persistence of enteroviruses in muscle tissue;   brain; and gut; increased detection of viral RNA via PCR; increased antibodies
 * Herpesvirus

Heart

 * Smaller than normal left ventricle of the heart, small heart syndrome, and low cardiac output.
 * Mean age of death from heart failure of CFS patients is 58.7 years as compared to 83.1 years for the general population.

Circulation

 * reduced blood flow to the brain,     even in the absence of POTS/NMH
 * reduced blood flow to the heart
 * peripheral endothelial dysfunction, which is an established risk factor for cardiovascular disease

Blood

 * reduced blood volume
 * abnormally shaped of red blood cells
 * reduced oxygen uptake in hemoglobin

Gastrointestinal tract

 * lower levels of Bifidobacteria, Escherichia coli and higher levels of aerobic bacteria, in particular Enterococcus and Streptococcus species
 * higher levels of enterococcus bacteria in CFS patients were associated with more severe neurological and cognitive dysfunction
 * Significantly increased proportions of Firmicutes and Bacteroides
 * CFS patients may suffer from small intestinal bacterial overgrowth (SIBO) at high rates
 * Higher levels of serum IgA and IgM against lipopolysaccharides (LPS), a major component of the outer membrane of gram-negative bacteria, indicating translocation. Serum IgA was significantly correlated to the severity of illness.

Liver

 * Reduced liver volume

Nutrition

 * low red blood cell magnesium
 * low serum carnitine

Metabolism

 * Metabolic abnormalities in chronic fatigue syndrome/myalgic encephalomyelitis: a mini-review

Cellular respiration

 * abnormalities  in cellular respiration including a reduction in glycolysis, including impaired pyruvate dehydrogenase
 * increased lactic acid
 * reduction in metabolites reflecting a slowed metabolism

Exercise

 * reduced pain threshold
 * translocation of bacteria
 * loss of capacity to recover from acidosis on repeat exercise
 * increased expression of sensory, adrenergic and immune genes following muscle exertion
 * decreased oxygen utilization

Learn more

 * Cellular Immune Function in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) (2019) - original research article
 * #MEAction ME/CFS Research Summary