chorea

Chorea is a hyperkinetic movement disorder characterized by brief, irregular, involuntary movements that flow from one muscle group to another. Movements are often rapid, unpredictable, and may affect the face, limbs, and trunk. They may worsen with voluntary activity or stress and typically lessen with sleep. Chorea is a sign of an underlying condition rather than a disease itself, and its presentation can be isolated or accompanied by cognitive or behavioral changes.

Common causes include Huntington disease (an autosomal dominant neurodegenerative disorder due to HTT gene expansion), Sydenham chorea following streptococcal infection, and drug-related chorea from antipsychotics or other dopaminergic agents. Metabolic and autoimmune conditions (thyroid disease, lupus), infectious or inflammatory processes, Wilson disease (copper metabolism disorder), vascular lesions in the basal ganglia, and pregnancy-related chorea can also produce choreiform movements.

Diagnosis relies on clinical assessment supported by targeted testing. History and examination guide evaluation for infectious, autoimmune, metabolic, and genetic etiologies. Laboratory studies may include thyroid function, inflammatory markers, autoimmune panels, and infectious serologies; Huntington disease genetic testing; copper studies for Wilson disease; and relevant imaging, typically brain MRI, to assess basal ganglia integrity and rule out structural causes.

Management focuses on treating the underlying cause and reducing troublesome movements. Interventions include dopamine-blocking or VMAT2-inhibiting medications (for example, tetrabenazine or deutetrabenazine) and atypical antipsychotics (risperidone, olanzapine) for symptom relief, with benzodiazepines for associated anxiety or agitation. Specific etiologies are addressed accordingly (penicillin for rheumatic fever, chelation for Wilson disease, physical and occupational therapy, and multidisciplinary care for Huntington disease). Prognosis varies by cause; Sydenham chorea often resolves over months, while Huntington disease is progressive.