[Chorea. Causes, diagnosis, and therapy].

The differential diagnosis of chorea includes a growing number of rare diseases. This article gives hints on clinical differences and possible laboratory investigations which may help to identify the underlying disease. The majority of hereditary chorea cases are caused by Huntington's disease. Different courses of disease can be distinguished depending on age at disease onset. The diagnosis can be confirmed genetically. Predictive testing is also possible but should be applied with caution only following internationally accepted guidelines. Our knowledge about treatment of chorea is limited, and studies have focused on the use of neuroleptics only. Their value is often outweighed by serious side effects. All efforts to find disease-modifying therapies for Huntington's disease had negative outcomes so far. To face these therapeutic limitations, the European Huntington's Disease Network was formed as a platform supporting the development and undertaking of clinical studies in Huntington's disease to improve care for these patients.