Muscle fatigability

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Revision as of 22:13, July 8, 2019 by Kmdenmark (talk | contribs) (c/e)

Muscle fatigability in ME is a symptom in which muscles become weaker after minor exertion and a long period (3-5 days or longer) may elapse before full muscle power is restored. According to Melvin Ramsay, it is the defining feature of myalgic encephalomyelitis, without which a diagnosis of ME should not be made,[1] though this symptom is noted to improve during remission. Similar muscle effects are known to occur in other neurological diseases such as multiple sclerosis[2] and post-polio syndrome.[3]

Prevalence[edit | edit source]

  • In a 2001 Belgian study, 84.3% of patients meeting the Fukuda criteria and 88.3% of patients meeting the Holmes criteria, in a cohort of 2073 CFS patients, reported hot flushes.[4]

Symptom recognition[edit | edit source]

  • In the Holmes criteria, unexplained generalized muscle weakness is an optional criteria for diagnosis, under the section Minor Symptom Criteria.[6]

Notable studies[edit | edit source]

Possible causes[edit | edit source]

  • Muscle biopsies have shown evidence of mitochondrial degeneration,[7] deletions of mitochondrial DNA,[8][9] and the reduction of mitochondrial activity.[10]
  • In addition, evidence of oxidative damage to muscles has been found in CFS.[11]
  • Studies have found reduced levels of serum carnitine which return to normal after recovery and correlate with symptom severity.[12]
  • Exercise has also been found to induce both early and excessive lactic acid formation in the muscles[13] with a reduced intraceullar concentrations of ATP and acceleration of glycolysis.[14]
  • Neurologist Peter Behan noted that ME patients were found to lack an important muscle enzyme called myoadenylate deaminase. An attempt has not been made to reproduce this finding in published research.[15]

Potential treatments[edit | edit source]

Learn more[edit | edit source]

See also[edit | edit source]

References[edit | edit source]