Chorea, or (rarely) choreia, (/kəˈriə/) is an abnormal involuntary movement disorder, characterized by quick movements of the hands or feet. It is one of a group of neurological disorders called dyskinesias. The term chorea is derived from Ancient Greekχορεία (choreia) 'dance', as the movements of the body is comparable to dancing.
The term hemichorea refers to chorea of one side of the body, such as chorea of one arm but not both (analogous to hemiballismus).
Presentation
Chorea is characterized by brief, semi-directed, irregular movements that are not repetitive or rhythmic, but appear to flow from one muscle to the next. These 'dance-like' movements of chorea often occur with athetosis, which adds twisting and writhing movements. Walking may become difficult and include odd postures and leg movements. Unlike ataxia, which affects the quality of voluntary movements, or Parkinsonism, which is a hindrance of voluntary movements, the movements of chorea and ballism occur on their own, without conscious effort. Thus, chorea is said to be a hyperkinetic movement disorder. When chorea is serious, slight movements will become thrashing motions; this form of severe chorea is referred to as ballism, or ballismus.[citation needed]
Causes
Huntington's disease
Huntington's disease is a neurodegenerative disease and most common inherited cause of chorea. The condition was formerly called Huntington's chorea but was renamed because of the important non-choreic features including cognitive decline and behavioural change.[1]
Sydenham's chorea occurs as a complication of streptococcal infection. Twenty percent (20%) of children and adolescents with rheumatic fever develop Sydenham's chorea as a complication. It is increasingly rare, which may be partially due to penicillin, improved social conditions, and/or a natural reduction in the bacteria (Streptococcus) it has stemmed from. Psychological symptoms may precede or accompany this acquired chorea and may be relapsing and remitting. The broader spectrum of paediatric autoimmune neuropsychiatric disorders associated with streptococcal infection can cause chorea and are collectively referred to as PANDAS.[2]
Chorea gravidarum refers to choreic symptoms that occur during pregnancy. If left untreated, the disease resolves in 30% of patients before delivery but, in the other 70%, it persists. The symptoms then progressively disappear in the next few days following the delivery.[2]
There is no standard course of treatment for chorea. Treatment depends on the type of chorea and the associated disease. Although there are many drugs that can control it, no cure has yet been identified.
