A Systematic Review of Treatment Outcome in Patients with Dopa-responsive Dystonia (DRD) and DRD-Plus

BackgroundDopa-responsive dystonia (DRD) and DRD-plus are inherited metabolic disorders of the dopamine synthetic pathway that have considerable clinical, biochemical, and genetic heterogeneity. Dopamine is the main deficient neurotransmitter; however, a deficiency in norepinephrine and serotonin can coexist, depending on the gene and its degree of defect. Therefore, even though levodopa is the mainstay of therapy, response to levodopa can be suboptimal and, thus, other drugs are tried. Methods and ResultsThe authors searched for reports of DRD and DRD-plus and reviewed the drugs used, their response and side effects, and neurologic outcomes, including motor and cognition. Based on the current results, a recommended treatment plan is presented according to the type of enzyme defect in patients with DRD and DRD-plus. ConclusionsIt is important to recognize the features of DRD and DRD-plus, because many of them have a good clinical response to the appropriate treatment. The aim of this review is to help guide clinicians with planning treatment for patients with DRD and DRD-plus.