Makindo Medical Notes

Related Subjects: |Neurological History taking

The term "chorea" is derived from the Greek word "choreia", meaning "dancing," from which the term choreography also originates. Ballismus is a more severe form of chorea, characterized by violent, flinging movements.

About

• Chorea and Ballismus are movement disorders characterized by irregular, involuntary movements.
• Chorea involves abrupt, rapid, and unsustained movements, while ballismus presents with more severe, flinging limb movements.

Clinical Features

• Involuntary, abrupt, rapid, brief, and unsustained irregular movements.
• Movements often described as "dance-like."
• Typically occur at rest, with normal coordination preserved.
• Milkmaid's grip sign: Difficulty maintaining a steady grip (similar to the repetitive motion of milking).
• Clumsy gait and walking difficulties.
• Explosive bursts of dysarthric speech.
• Ballismus: A severe form of chorea, involving violent, flinging movements of the limbs.

Pathophysiology

• Thought to involve an imbalance of dopamine and acetylcholine within the basal ganglia, leading to disrupted motor control.

Causes of Chorea

• Rheumatic fever – Sydenham's chorea (a post-infectious immune response)
• Huntington's disease
• Systemic lupus erythematosus (SLE)
• Antiphospholipid syndrome
• Senile chorea (seen in older adults)
• Chorea gravidarum (associated with pregnancy or oral contraceptives)
• Wilson's disease (a disorder of copper metabolism)
• Ataxia telangiectasia
• Neuroacanthocytosis (involves abnormal red blood cells)
• HIV-related chorea
• Dentatorubral-pallidoluysian atrophy (DRPLA)
• Hyperthyroidism
• Poisoning: Carbon monoxide, manganese, or organophosphate exposure
• Drug-induced (e.g., levodopa, neuroleptics)

Investigations

• Urea & Electrolytes (U&E) and Liver Function Tests (LFTs) – to rule out metabolic or systemic causes.
• Antistreptolysin O Titre (ASOT) and Anti-DNAase B – to assess for recent streptococcal infection (linked to Sydenham's chorea).
• Anti-basal ganglia (neuronal) antibodies (ABGA) – used to investigate autoimmune causes.
• MRI Brain – may reveal structural abnormalities or basal ganglia involvement.
• Echocardiogram – indicated if rheumatic fever is suspected, to assess for cardiac involvement.

Management

• Tetrabenazine (Xenazine) – A dopamine-depleting agent often used for managing chorea. Care is needed due to risks of depression or suicidal ideation.
• Haloperidol (1 mg twice daily) or Quetiapine – Both antipsychotic medications can help manage involuntary movements, with smaller initial doses.
• Steroids – Sometimes used for Sydenham's chorea, though efficacy may vary.