chorea,athetosis and hemiballismus

Chorea is nonrhythmic, jerky, rapid, nonsuppressible involuntary movements, mostly of distal muscles or the face; movements may merge imperceptibly into purposeful or semipurposeful acts that mask the involuntary movements. Athetosis is nonrhythmic, slow, writhing, sinuous movements predominantly in distal muscles, often alternating with postures of the proximal limbs to produce a continuous, flowing stream of movement. Hemiballismus is usually a unilateral, nonrhythmic, rapid, nonsuppressible, violent, flinging movement of the proximal arm.

Chorea and athetosis often occur together (as choreoathetosis). They are manifestations of overactivity in certain pathways of the basal ganglia. Huntington’s disease (see Movement and Cerebellar Disorders: Huntington’s Disease) is the most common degenerative disease causing chorea. Other causes include thyrotoxicosis, paraneoplastic syndromes, SLE affecting the CNS, other autoimmune disorders, and drugs (eg, antipsychotics). Rheumatic fever sometimes leads to Sydenham’s chorea (see Rheumatic Fever: CNS). A tumor or infarct of the caudate nucleus can cause acute unilateral chorea (hemichorea). Chorea may occur as an isolated symptom in patients > 60 (as senile chorea); this chorea tends to be symmetric and does not cause dementia.

The cause is treated or corrected if possible. Sydenham’s chorea and chorea due to infarcts of the caudate nucleus often lessen over time. Chorea due to thyrotoxicosis usually lessens when thyroid dysfunction is corrected. In Huntington’s disease, drugs that suppress dopaminergic activity, such as antipsychotics (eg, risperidone

), and dopamine

drugs (eg, reserpine

, tetrabenazine) can be used. However, improvement may be limited.

Chorea gravidarum occurs during pregnancy, often in patients who had rheumatic fever. Chorea usually begins during the 1st trimester and resolves spontaneously by or after delivery. Treatment is sedation with barbiturates; other sedatives may harm the fetus. Rarely, a similar disorder occurs in women taking oral contraceptives.

Hemiballismus is caused by a lesion, usually an infarct, around the contralateral subthalamic nucleus. Although disabling, hemiballismus is usually self-limited, lasting 6 to 8 wk. Treatment with antipsychotics is often effective.

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: