Chorea.

Chorea is an involuntary movement disorder characterised by flowing and rhythmic in nature. Hyperkinetic movement disorders such as myoclonus may be mistaken for chorea. Pathogenes of chorea is complex and results from dysfunction of network between motor nucleus of thalamus and subcortical nuclei including globus pallidus interna. There are genetic and non genetic causes of chorea. Huntington's disease is most common genetic cause of chorea. Clinical manifestations of Huntington's disease are mainly neurological and psychiatric. Recently non neurological clinical manifestations of this disease have been described. Genetic test for Huntington's disease is available which may be done for diagnosis and detection of family members at risk of developing disease. Other genetic causes of chorea are neuroacanthocytosis and Wilson's disease. Treatment of genetic causes of chore is usually symptomatic with exception of Wilson's disease. Sydenham's chorea is a neurological manifestation of acute rheumatic fever and most important cause of chorea seen in paediatric population. Treatment includes penicillin prophylaxis and drugs such as sodium valproate and carbamazepine. Diagnosis of chorea is mainly clinical. Family history is very important in diagnosis of genetic causes of chorea. In other patients a detailed work up is required before a final diagnosis is made. Hematological and blood chemistry investigations are helpful in diagnosis of some of the patients. Neuro imaging may also be useful mainly in Huntington's disease patients. Metabolic disorders and drugs are very important causes of non genetic chorea. Early diagnosis is important because majority of the patients respond to the treatment.