From the Guidelines
Hemichorea evaluation and management require a comprehensive approach, focusing on identifying the underlying cause and providing symptomatic treatment, with dopamine-blocking agents being first-line therapy. The evaluation of hemichorea, characterized by involuntary, irregular, and non-repetitive movements on one side of the body, should include a thorough history, physical examination, and neuroimaging, such as MRI brain, to rule out structural lesions 1. Laboratory testing should include complete blood count, metabolic panel, thyroid function, and screening for autoimmune conditions.
Key Considerations
- Initial imaging, such as MRI brain, is crucial in the diagnostic workup, even if the diagnosis of Huntington disease (HD) is suspected, as it may help identify other potential etiologies 1.
- Genetic testing to determine the CAG repeat number for each allele is commercially available and the diagnostic test of choice for HD, and patients with suspected HD should undergo genetic counseling and testing to exclude or confirm HD 1.
- Symptomatic treatment of hemichorea typically involves dopamine-blocking agents, such as haloperidol, risperidone, olanzapine, or quetiapine, with the goal of reducing involuntary movements and improving quality of life.
Management Approach
- For symptomatic treatment, dopamine-blocking agents are first-line, with haloperidol starting at 0.5-1 mg twice daily and titrating as needed (maximum 5-10 mg/day).
- Alternative options include risperidone (0.5-3 mg twice daily), olanzapine (2.5-10 mg daily), or quetiapine (25-200 mg twice daily).
- In cases of hemichorea associated with hyperglycemia, strict glucose control is essential.
- For autoimmune causes, immunotherapy with corticosteroids (prednisone 1 mg/kg/day for 4-6 weeks with taper) may be necessary.
- Treatment duration varies based on etiology, with some cases requiring lifelong therapy while others may resolve with treatment of the underlying condition.
- Regular monitoring for medication side effects, particularly extrapyramidal symptoms with antipsychotics, is crucial for optimal management.
From the Research
Evaluation and Management of Hemichorea
Hemichorea is characterized by involuntary, irregular, and non-repetitive movements on one side of the body. The evaluation and management of hemichorea involve a variety of approaches, including pharmacological and non-pharmacological interventions.
- The treatment of chorea, including hemichorea, often involves the use of inhibitors of presynaptic vesicular monoamine transporter type 2 (VMAT2) such as tetrabenazine, deutetrabenazine, and valbenazine 2.
- Dopamine receptor blockers, anti-epileptics, and anti-glutamatargics may also be used in the treatment of chorea 2.
- In cases of hemichorea-hemiballismus associated with non-ketotic hyperglycaemia, treatment with a combination of amantadine, clonazepam, and tetrabenazine may be effective 3.
- Deutetrabenazine, a deuterated form of tetrabenazine, has been shown to be effective in reducing chorea in Huntington's disease, with a similar efficacy profile to tetrabenazine but with fewer adverse effects 4.
- Chemodenervation may also be used in conjunction with tetrabenazine to treat hemichorea-hemiballismus associated with dystonia 5.
- The management of chorea in Huntington's disease often involves the use of tetrabenazine, tiapride, olanzapine, and risperidone, with the goal of reducing chorea and improving motor symptom severity and psychiatric symptoms 6.
Treatment Options
The treatment options for hemichorea include:
- Tetrabenazine: a VMAT2 inhibitor that depletes striatal dopamine and is considered a first-line treatment for chorea 2, 3, 6, 5.
- Deutetrabenazine: a deuterated form of tetrabenazine that has a longer half-life and may have fewer adverse effects 4.
- Amantadine: an anti-parkinsonian medication that may be used in combination with other medications to treat hemichorea-hemiballismus 3.
- Clonazepam: a benzodiazepine that may be used to treat anxiety and other symptoms associated with hemichorea-hemiballismus 3.
- Chemodenervation: a procedure that involves the injection of a neurotoxin into affected muscles to reduce dystonia and other movement disorders 5.