Parkinsonism, dystonia, and hemiatrophy

Hemiatrophy has been reported in association with variety of neurologic con ditions, including parkinsonism. Patients with the hemiparkinson-hemiatroph y syndrome (HP-HA) have asymmetric parkinsonism with limb atrophy on the mo re affected side. Several authors have suggested that asymmetric brain dama ge early in life results in both atrophy and parkinsonism. Dopa-responsive dystonia (DRD) is a disease in which a deficiency of tetrahydrobiopterin, o r, less commonly, of tyrosine hydroxylase, results in levodopa-responsive d ystonia with parkinson features in children. We have recently identified fo ur patients with DRD who had asymmetric dystonia and limb atrophy on the mo re affected side. Based on these patients, we suggest that a deficiency of the nigrostriatal dopamine system may, by itself, be sufficient to cause bo dy atrophy and may underlie the limb atrophy in both DRD and HP-HA.