Dopaminergic response in Parkinsonian phenotype of Machado-Joseph disease.

We report on a patient with genetically proven Machado-Joseph Disease (MJD) presenting with signs indistinguishable from Parkinson's disease (PD), including levodopa response and typical levodopa-induced motor fluctuations. Only after 10 years of prolonged benefit from levodopa and different dopamine agonists (DA), the patient developed cerebellar ataxia and pyramidal signs. Preferential D3-receptor-stimulating dopamine agonists especially showed a benefit at the time, when D2 receptor binding was reduced in IBZM SPECT. This is the first report of a meaningful response to DA in MJD.