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Autosomal recessive spastic paraplegia type 21

Disease definition

Autosomal recessive spastic paraplegia type 21 is a complex type of hereditary spastic paraplegia characterized by an onset in adolescence or adulthood of slowly progressive spastic paraparesis associated with the additional manifestations of apraxia, cognitive and speech decline (leading to dementia and akinetic mutism in some cases), personality disturbances and extrapyramidal (e.g. oromandibular dyskinesia, rigidity) and cerebellar (i.e. dysdiadochokinesia and incoordination) signs. Subtle abnormalities (e.g. developmental delays) may be noted earlier in childhood. A thin corpus callosum and white matter abnormalities are equally reported on magnetic resonance imaging.


Classification level: Disorder
  • Synonym(s):
    • Mast syndrome
    • SPG21
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Childhood, Adolescent, Adult
  • ICD-10: G11.4
  • ICD-11: 8B44.01
  • OMIM: 248900
  • UMLS: C1855346
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information

General public

Disease review articles


ERN : produced/endorsed by ERN(s)
FSMR : produced/endorsed by FSMR(s)
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