The syndrome of chorea is usually classified under four main groups: (1) the infectious group, Sydenham's chorea and chorea gravidarum; (2) the psychogenic and hereditary group, comprising the spasmodic tics and Huntington's chorea; (3) the myokymia disorders, including symptomatic fibrillary twitchings and Friedreich's myoclonus multiplex, and (4) choreiform movements associated with organic conditions, occurring in hemiplegias, in the chronic choreas of childhood and in other structural brain disturbances, such as those associated with epidemic encephalitis. Many interesting clinical pictures have been reported, accompanying the recent epidemic of encephalitis. Bizarre muscular movements of almost every kind have been described.
In a series of 154 cases, I have observed choreiform movements eight times. In one of these, a diagnosis of Sydenham's chorea was made during the first week, after which the patient became lethargic, complained of diplopia and presented the usual picture of epidemic encephalitis. Another patient, during the third week of