title: What Is Not in the Name? Dopa-Responsive Dystonia May Respond to More Than L-Dopa.
abstract: Classic L-dopa-responsive dystonia is characterized by the triad of dystonia, diurnal fluctuation of signs, and dramatic response of signs to low-dose L-dopa therapy. Dopa-responsive dystonia succinctly summarizes the relevant clinical features. However, literal application of this label or consideration of dopa-responsive dystonia as a diagnostic end without molecular and/or biochemical definition may contribute to misdiagnosis and incomplete treatment in dopa-responsive conditions that impair synthesis of monoamine neurotransmitters besides dopamine.
  
  
  
  We describe and provide video for twin patients with a rare form of dopa-responsive dystonia due to sepiapterin reductase deficiency. As is typical in dopa-responsive dystonia, these patients displayed dramatic improvement with L-dopa/carbidopa therapy. However, treatment was suboptimal until 5-hydroxytryptophan was added to address their serotonergic deficit.
  
  
  
  Our report highlights the limitations of the dopa-responsive dystonia label and increases awareness of sepiapterin reductase deficiency and other conditions that may present as dopa-responsive dystonia. We provide a diagnostic and therapeutic approach to guide the clinician in evaluating and treating individuals with dopa-responsive dystonia.
authors.affiliation: Department of Neurosciences and Pediatrics, University of California San Diego and Rady Children's Hospital, San Diego, California. Electronic address: jrfriedman@rchsd.org.
authors.forename: Jennifer R
authors.initials: JR
authors.lastname: Friedman
mesh_terms: D006916:5-Hydroxytryptophan / Q000627:therapeutic use*; D000293:Adolescent; D018726:Anti-Dyskinesia Agents / Q000627:therapeutic use*; D002230:Carbidopa / Q000627:therapeutic use*; D004200:Diseases in Twins; D018491:Dopamine Agonists / Q000627:therapeutic use; D004338:Drug Combinations; D004421:Dystonia / Q000188:drug therapy* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use*; D008297:Male; D008661:Metabolism, Inborn Errors / Q000188:drug therapy* / Q000503:physiopathology; D011596:Psychomotor Disorders / Q000188:drug therapy* / Q000503:physiopathology; D018490:Serotonin Agents / Q000627:therapeutic use
chemical_list: D018726:Anti-Dyskinesia Agents; D018491:Dopamine Agonists; D004338:Drug Combinations; D018490:Serotonin Agents; C009265:carbidopa, levodopa drug combination; D007980:Levodopa; D006916:5-Hydroxytryptophan; D002230:Carbidopa
keywords: DRD; cerebral palsy; dopa responsive; dystonia; sepiapterin