Chorea is not a disease but a neurological syndrome characterized by abnormal, disordered and involuntary movements. What pathologies can cause it? How is the diagnosis made? Highlight with Dr Anne-Gaëlle Corbillé, neurologist at the University Hospital of Nantes.
Definition: what is a chorea?
Chorea is a neurological syndrome that is defined by abnormal, disordered and involuntary movements. On the other hand, Huntington’s chorea has a hereditary origin, it is due to the destruction of certain neurons, the disease most often appearing around the age of 40. There is no cure but there are treatments to alleviate the symptoms of the disease. Physical therapy is also recommended to improve balance and exercise muscles.
What are the symptoms of chorea?
Chorea is not a disease in itself but a symptomwhich is characterized by abnormal and involuntary movements that occur suddenly and randomly. Chorea can affect different areas of the body or diffuse. It only disappears during sleep. “Most of the time, these movements are associated with a hypotonia, i.e. low muscle tone. Chorea is increased by strong emotions stress“, specifies Dr. Anne-Gaëlle Corbillé, neurologist.
What diseases can cause chorea?
Chorea results from a dysfunction of one or more brain regions involved in the control of movements. There are two causes of chorea:
► Acquired chorea: metabolic (such as hypo or hyperglycaemia, hyperthyroidism), iatrogenic (medication), autoimmune (anti-phospholipid syndrome), paraneoplastic, infectious or vascular NGC lesions. Sydenham’s chorea (also called St. Vitus’ dance or Sydenham’s disease) is a rare cause of chorea; it corresponds to a complication of acute articular rheumatism, linked to a streptococcal infection.
► Genetic chorea, Huntington’s disease being the most common genetic cause.
The diagnosis of chorea is based on clinical examination of the patient. The doctor then seeks to determine the cause of the chorea. For this, he find out if the patient has other neurological signs (cognitive disorders, balance disorders). He then prescribes additional examinations, in particular a genetic analysis to detect Huntington’s disease. A biological assessment will be prescribed to screen for possible metabolic disorders (thyroid hormones, blood sugar, copper overload), infections (HIV, for example) or antibodies. A brain MRI will look for lesions of the basal ganglia or signs of Huntington’s disease.
What is the treatment for chorea?
The treatment is that of the cause. For example, in case of hyperthyroidism or hyperglycemia, chorea will disappear spontaneously with correction of metabolic disorder. Sydenham’s chorea gradually disappears. If chorea is the result of drug treatment, this will usually disappear when treatment is stopped. If necessary, a treatment with anti-dopaminergic action (neuroleptic) may be useful.
Thanks to Dr Anne-Gaëlle Corbillé, neurologist at Nantes University Hospital.