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Lewis-Sumner syndrome

Disease definition

Lewis-Sumner syndrome (LSS) is a rare acquired demyelinating polyneuropathy characterized by asymmetrical distal weakness of the upper or lower extremities and motor dysfunction with adult onset. It is considered to be a variant of chronic inflammatory demyelinating polyneuropathy.


Classification level: Subtype of disorder
  • Synonym(s):
    • MADSAM
    • Multifocal acquired demyelinating sensory and motor neuropathy
  • Prevalence: 1-9 / 1 000 000
  • Inheritance: Not applicable 
  • Age of onset: All ages
  • ICD-10: G61.8
  • OMIM: -
  • UMLS: C1695985
  • MeSH: -
  • GARD: -
  • MedDRA: 10065580

Detailed information


Additional information

Further information on this disease

Specialised Social Services

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