Chorea is most commonly associated with which disease?

• A. Huntington's disease
• B. Parkinson's disease
• C. Alzheimer's disease
• D. Multiple Sclerosis

Answer: (A)

Chorea is a rapid, irregular, dance-like movement produced by disruption of the basal ganglia circuits that normally modulate movement. In Huntington's disease, there is degeneration of the striatal GABAergic neurons in the caudate nucleus and putamen. This reduces inhibitory output from the striatum to the thalamus, allowing excessive thalamocortical excitation and resulting in choreiform movements. This combination of characteristic movement plus the known pattern of striatal degeneration makes Huntington's disease the classic condition associated with chorea. In contrast, Parkinson's disease mainly presents with bradykinesia, rigidity, and resting tremor; Alzheimer's disease is primarily a cognitive disorder; and multiple sclerosis can cause a variety of motor symptoms but chorea is not its hallmark feature.