[Response to haloperidol and analysis of growth curve in hereditary progressive dystonia with marked diurnal fluctuation].

A case of 10-year-old female with hereditary progressive dystonia with marked diurnal fluctuation (HPD) was described. Her development was normal. Then at the age of eight, she developed dystonia of the left lower extremity that became noticeable toward evening but subsided after taking sleep. And the velocity of height gain decreased at the age of nine (from 5 cm to 3.6 cm per year). Before the diagnosis of HPD, small doses of haloperidol (0.015 mg/kg/day) were given to her. Thereafter she developed progressive dystonia of all extremities and could not walk. Administration of haloperidol was discontinued, and an attempt to reverse the dystonia with L-Dopa was made. Prior to treatment with L-Dopa, a reduced concentration of cerebrospinal fluid homovanillic acid (10 ng/ml) was found. And her height was 130.5 cm (-1.33 SD) at the age of ten. Treatment with L-Dopa (18 mg/kg/day) markedly improved her symptoms within four days. This improvement has been maintained for six years without a need for increasing the doses and without neurological side effects. At the age of sixteen her height was 162.3 cm (+1.0 SD). These findings suggest a diminished dopaminergic activity and a increased susceptibility to dopamine receptor blockade in HPD.