What is the appropriate management for choreiform movements?

Management of Choreiform Movements

Treat the underlying cause first, then use VMAT2 inhibitors (tetrabenazine, deutetrabenazine, or valbenazine) as first-line symptomatic therapy for persistent, functionally disabling chorea. 1, 2

Initial Diagnostic Workup

Before initiating symptomatic treatment, identify and address reversible causes:

Essential Laboratory Tests

• Measure serum ceruloplasmin to exclude Wilson disease, particularly in younger patients 1
• Check thyroid function, serum calcium, phosphorus, parathyroid hormone, and blood glucose to identify metabolic causes 1
• In children with acute-onset chorea, obtain antistreptolysin O, anti-deoxyribonuclease B, or streptozyme to document streptococcal infection (Sydenham's chorea accounts for 96% of pediatric cases) 1
• Measure alpha-fetoprotein if ataxia-telangiectasia is suspected 1

Imaging

• Obtain brain MRI without contrast as the optimal imaging modality to identify structural lesions, vascular abnormalities, basal ganglia changes, and neurodegenerative patterns 1, 2
• Note that neuroimaging in Sydenham's chorea rarely contributes to diagnosis and should be reserved for atypical presentations 1

Genetic Testing

• Order genetic testing for CAG repeat expansions in the huntingtin gene when Huntington's disease is suspected (the most common cause of adult-onset chorea) 1, 2

Etiology-Specific Treatment

Drug-Induced Chorea

• Immediately discontinue the offending agent (most commonly antipsychotics, antiemetics like metoclopramide, or dopamine antagonists) 1, 3
• Monitor patients on long-term neuroleptics periodically to detect tardive dyskinesia development 1
• Elderly patients and those with basal ganglia lesions have substantially increased susceptibility 3

Autoimmune Chorea

• For systemic lupus erythematosus-associated chorea, use glucocorticoids alone or combined with immunosuppressive agents (azathioprine or cyclophosphamide) 1, 2
• In refractory cases with generalized lupus activity, administer pulse intravenous methylprednisolone together with intravenous cyclophosphamide 1
• For antiphospholipid antibody-associated chorea, initiate antiplatelet therapy and/or anticoagulation, especially when other antiphospholipid syndrome manifestations are present 1, 2

Metabolic Causes

• Correct thyroid dysfunction, calcium-phosphate abnormalities, or glucose disturbances 1
• In hemodialysis patients (12–24 months or longer), screen plasma aluminum levels; concentrations of 150–350 µg/L indicate dialysis encephalopathy 1

Sydenham's Chorea (Pediatric)

• Recognize that 30% present with unilateral (hemichorea) movements 1
• Associated features include behavior change (46%), dysarthria (67%), gait disturbance (51%), and deteriorating handwriting (29%) 1
• Carditis occurs concurrently in 44% of cases and requires evaluation 1

Symptomatic Pharmacologic Management

First-Line Agents (VMAT2 Inhibitors)

• Tetrabenazine, deutetrabenazine, or valbenazine are the treatments of choice for functionally disabling chorea through striatal dopamine depletion 1, 4, 5
• Deutetrabenazine and valbenazine are FDA-approved alternatives with suggested fewer peak-dose side effects compared to tetrabenazine 1, 5
• Start with a low dose and titrate upward with close monitoring for adverse effects 5

Alternative Dopamine Antagonists

• Dopamine receptor blockers (antipsychotics) are usually effective when VMAT2 inhibitors are unavailable or not tolerated 2, 4
• Haloperidol, sulpiride, and quetiapine control chorea and associated psychiatric abnormalities in Huntington's disease 1
• In European countries, tiapride is a preferred first-choice agent 5
• Olanzapine and risperidone show beneficial effects on motor symptom severity and psychiatric symptoms 5

Additional Pharmacologic Options

• Anti-epileptics and anti-glutamatergic agents are used by some clinicians, though evidence is less robust 4
• Pridopidine (a "dopamine stabilizer") is under investigation 4

Supportive and Advanced Therapies

Non-Pharmacologic Management

• Provide speech therapy and occupational therapy for functional improvement 1
• These supportive therapies are essential regardless of pharmacologic intervention 1

Deep Brain Stimulation

• Reserve deep brain stimulation for patients with disabling chorea despite optimal medical therapy 4
• Globus pallidus internus is the most common target 6
• Patients with dystonia as a major manifestation benefit more from high-frequency stimulation; those with chorea and dysarthria are suitable for low-frequency stimulation 6
• Thalamic stimulation has shown promise in children with choreiform disorders due to intracerebral hemorrhage or cerebral palsy 7

Critical Pitfalls to Avoid

• Do not assume all chorea in patients on antipsychotics is drug-induced—systemic lupus erythematosus with antiphospholipid antibodies requires different management 3
• Do not overlook anticholinergic burden from medications like diphenhydramine and hydroxyzine, which can contribute to movement disorders 3
• Documenting recent streptococcal infection in Sydenham's chorea can be difficult due to the long latent period between infection and chorea onset 1
• Distinguish choreiform movements from tics, athetosis, conversion reactions, and hyperkinesis to avoid misdiagnosis 1
• In ataxia-telangiectasia patients, avoid ionizing radiation and x-rays due to increased radiosensitivity 1
• Use deferoxamine cautiously in hemodialysis patients with aluminum loading, as high doses (20–40 mg/kg) can precipitate acute neurotoxicity and fatal outcomes 1