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Semantic dementia

Disease definition

Semantic dementia (SD) is a form of frontotemporal dementia (FTD; see this term), characterized by the progressive, amodal and profound loss of semantic knowledge (combination of visual associative agnosia, anomia, surface dyslexia or dysgraphia and disrupted comprehension of word meaning) and behavioral abnormalities, attributable to the degeneration of the anterior temporal lobes.


Classification level: Disorder
  • Synonym(s):
    • Semantic primary progressive aphasia
    • Semantic variant PPA
  • Prevalence: -
  • Inheritance: Multigenic/multifactorial or Not applicable 
  • Age of onset: Adult
  • ICD-10: G31.0
  • ICD-11: 6D83
  • OMIM: 172700  600274
  • UMLS: C0338462
  • MeSH: -
  • GARD: 10792
  • MedDRA: -

Detailed information

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