Exercise induced steroid dependent dystonia, ataxia, and alternating hemiplegia associated with epilepsy.

This paper describes a 20 year old woman with a new combination of neurological impairments in which the motor phenomena were responsive to corticosteroid treatment. She had lifelong moderate learning impairment. A variable ataxia with cerebellar characteristics was present from early life, with early severe exacerbation when seizures were uncontrolled. Atypical absence and simple and complex partial seizures were present from the first year of life and EEG abnormalities were maximal in the right parietal region, concordant with a mild non-specific abnormality of the white matter in the region of the trigone. Episodes of alternating hemiplegia occurred from 11 years, unassociated with seizures. Exercise induced dystonia occurred from the age of 5. After 10-20 minutes walking, her right foot would turn in and the right leg would stiffen, followed by the left and by falling and inability to get up for several minutes. Prednisolone improved her ataxia and was associated with cessation of both seizures and exercise induced dystonia. This adds a new syndrome to the corticosteroid responsive motor disorders associated with epilepsy.