Morvan syndrome

What is Morvan syndrome?

Morvan syndrome is a rare, life-threatening, acquired neurologic disease characterized by neuromyotonia, dysautonomia and encephalopathy with severe insomnia. Signs involving central (e.g. hallucinations, confusion, amnesia, myoclonus), autonomic (e.g. variations in blood pressure, hyperhidrosis) and peripheral (e.g. painful cramps, myokymia) hyperactivity, as well as systemic manifestations (such as weight loss, pruritus, fever), are reported. Thymoma is present in some cases.

Other condition names

  • Limbic encephalitis-neuromyotonia-hyperhidrosis-polyneuropathy syndrome
  • Morvan fibrillary chorea


  • Worldwide: <1 in 1,000 000

Age of Onset

  • Adult
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