Expanding phenotype and clinical analysis of tyrosine hydroxylase deficiency

J Child Neurol. 2011 Feb;26(2):179-87. doi: 10.1177/0883073810377014. Epub 2010 Sep 7.


This study included 12 Chinese patients with a wide spectrum of phenotypes of tyrosine hydroxylase deficiency. Seven females and 5 males, aged 2.2 to 41 years, had phenotypes ranging from severe type with onset at infancy to mild type with onset after 3 years of age. Patients with the severe type had encephalopathy with poor treatment response or infantile parkinsonism with motor delay. Patients with the less common mild type had dopa-responsive dystonia or a newly recognized predominant symptom of myopathy. Female siblings had more severe phenotypes. The phenotype and treatment outcomes were strongly related to a homovanillic acid level and homovanillic acid/5-hydroxyindolacetic acid ratio of less than 1 in the cerebrospinal fluid. Hyperprolactinemia was found in 50% of the severe cases. Levodopa was the mainstay of treatment, and early addition of selegiline resulted in a remarkable response in some patients. Treatment response for mild-type patients is universally good even with a treatment delay of 10 years after onset of neurological symptoms.

MeSH terms

  • Adolescent
  • Adult
  • Child
  • Child, Preschool
  • Deficiency Diseases / drug therapy*
  • Dopamine Agents / therapeutic use*
  • Drug Therapy, Combination
  • Female
  • Humans
  • Levodopa / therapeutic use*
  • Male
  • Parkinsonian Disorders / drug therapy*
  • Parkinsonian Disorders / genetics
  • Phenotype
  • Prolactin / blood
  • Selegiline / therapeutic use*
  • Severity of Illness Index
  • Treatment Outcome
  • Tyrosine 3-Monooxygenase / deficiency*


  • Dopamine Agents
  • Selegiline
  • Levodopa
  • Prolactin
  • Tyrosine 3-Monooxygenase