Adult-onset dystonia: Atypical manifestation of Segawa disease

A 33-year-old woman developed exercise-induced limb and trunk dystonia with marked diurnal fluctuations. Treatment with levodopa improved her symptoms considerably but incompletely. Molecular genetic analysis revealed a mutation in GTP cyclohydrolase 1 (GCH1). This report illustrates the variability of Segawa disease and underlines the importance of a levodopa test in patients with uncommon dystonic symptoms. © 2007 Movement Disorder Society