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What is A 40-year-old man is brought to the doctor by his family for the rapid intellectual decline. Examination shows fast semi-purposive movements in hands. His father and grandfather had a similar illness. What is the diagnosis? and explain in detail?
The fast semi-purposive movements - Chorea. With advancing age chorea reduces and dystonia, rigidity, and myoclonus appear. Huntington's disease has an autosomal dominant pattern of inheritance . The intellectual decline is a common feature. Presenile dementia is seen in Down's syndrome Lewy body dementia presents with hallucinations, delusions, and dementia. Coicobasal degeneration/Alien hand syndrome-Asymmetric dystonia, apraxia (Loss of visuospatial skills), focal limb myoclonus