Which disorder features cognitive decline with chorea and is commonly treated with tetrabenazine for chorea?

Which disorder features cognitive decline with chorea and is commonly treated with tetrabenazine for chorea?

• A. Alzheimer disease
• B. Huntington disease
• C. Parkinson disease
• D. Lewy body dementia

Answer: (B)

Huntington disease presents with a combination of cognitive decline, psychiatric changes, and choreiform movements. The chorea arises from degeneration in the striatum (caudate and putamen), which disrupts motor pathways and leads to involuntary, irregular movements. It’s caused by an autosomal dominant CAG repeat expansion in the huntingtin gene, with anticipation over generations. For controlling chorea in Huntington disease, tetrabenazine is commonly used because it depletes presynaptic monoamines (notably dopamine) by inhibiting VMAT2, reducing dopaminergic stimulation of motor circuits and thereby diminishing chorea. In contrast, Alzheimer disease mainly features progressive memory loss without prominent chorea; Parkinson disease presents with bradykinesia, rigidity, and resting tremor rather than chorea; Lewy body dementia includes parkinsonism with fluctuations and visual hallucinations, not the classic Huntington chorea pattern.

Huntington disease presents with a combination of cognitive decline, psychiatric changes, and choreiform movements. The chorea arises from degeneration in the striatum (caudate and putamen), which disrupts motor pathways and leads to involuntary, irregular movements. It’s caused by an autosomal dominant CAG repeat expansion in the huntingtin gene, with anticipation over generations. For controlling chorea in Huntington disease, tetrabenazine is commonly used because it depletes presynaptic monoamines (notably dopamine) by inhibiting VMAT2, reducing dopaminergic stimulation of motor circuits and thereby diminishing chorea. In contrast, Alzheimer disease mainly features progressive memory loss without prominent chorea; Parkinson disease presents with bradykinesia, rigidity, and resting tremor rather than chorea; Lewy body dementia includes parkinsonism with fluctuations and visual hallucinations, not the classic Huntington chorea pattern.