Juvenile levodopa-responsive Parkinsonism with early orobuccolingual dyskinesias and cognitive impairment.

A 13-year old girl presented with slowly progressive rest tremor of the hands, bradykinesia, and rigidity. The symptoms improved with dopaminergic medications, but severe drug-induced dyskinesias developed early. She subsequently developed cognitive slowing and difficulty initiating saccadic eye movements. She went on to have deep brain stimulation surgery. Experts discuss the syndromal diagnosis and predict the underlying pathology. The pathological diagnosis is given and clinical learning points are considered.