Dopa-responsive Dystonia

Dopa-responsive dystonia (DRD) is a genetic movement disorder characterized by childhood-onset lower limb dystonia with diurnal fluctuation. Pathophysiology involves mutations affecting dopamine synthesis pathways, most commonly in the GCH1 gene. Diagnosis is clinical, supported by marked improvement with low-dose levodopa therapy. Management includes long-term levodopa, with careful titration to avoid dyskinesia. Prognosis is favorable with early treatment, allowing near-normal motor function in many patients.