title: Expanding phenotype and clinical analysis of tyrosine hydroxylase deficiency.
abstract: 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.
authors.affiliation: Department of Paediatrics, Chinese University of Hong Kong, Prince of Wales Hospital, Hong Kong SAR, China. yw1221@ha.org.hk
authors.forename: Wai-Lan
authors.initials: WL
authors.lastname: Yeung
authors.forename: Virginia C N
authors.initials: VC
authors.lastname: Wong
authors.forename: Kwok-Yin
authors.initials: KY
authors.lastname: Chan
authors.forename: Joannie
authors.initials: J
authors.lastname: Hui
authors.forename: Cheuk-Wing
authors.initials: CW
authors.lastname: Fung
authors.forename: Eric
authors.initials: E
authors.lastname: Yau
authors.forename: Chun-Hung
authors.initials: CH
authors.lastname: Ko
authors.forename: Ching-Wan
authors.initials: CW
authors.lastname: Lam
authors.forename: Chloe M
authors.initials: CM
authors.lastname: Mak
authors.forename: Simon
authors.initials: S
authors.lastname: Siu
authors.forename: Louis
authors.initials: L
authors.lastname: Low
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D003677:Deficiency Diseases / Q000188:drug therapy*; D015259:Dopamine Agents / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D007980:Levodopa / Q000627:therapeutic use*; D008297:Male; D020734:Parkinsonian Disorders / Q000188:drug therapy* / Q000235:genetics; D010641:Phenotype; D011388:Prolactin / Q000097:blood; D012642:Selegiline / Q000627:therapeutic use*; D012720:Severity of Illness Index; D016896:Treatment Outcome; D014446:Tyrosine 3-Monooxygenase / Q000172:deficiency*
chemical_list: D015259:Dopamine Agents; D012642:Selegiline; D007980:Levodopa; D011388:Prolactin; D014446:Tyrosine 3-Monooxygenase