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Pterin-4 alpha-carbinolamine dehydratase deficiency

Disease definition

Dehydratase deficiency or pterin-4 alpha-carbinolamine dehydratase (PCD) is considered a transient and benign form of hyperphenylalaninemia due to tetrahydrobiopterin deficiency (see this term), characterized by muscular hypotonia, irritability (detected by EEG), slow acquisition of psychomotor skills, age-dependent movement disorders, including dystonia and an accompanying excretion of 7-substituted pterins. Neurological developement is normal with dietary control of blood phenyalanine. PCD is inherited in an autosomal recessive manner.


Classification level: Subtype of disorder
  • Synonym(s):
    • Hyperphenylalaninemia due to dehydratase deficiency
    • Hyperphenylalaninemia due to pterin-4-alpha-carbinolamine dehydratase deficiency
    • Hyperphenylalaninemia with primapterinuria
  • Prevalence: Unknown
  • Inheritance: Autosomal recessive 
  • Age of onset: Neonatal
  • ICD-10: E70.1
  • OMIM: 264070
  • UMLS: C1849700
  • MeSH: -
  • GARD: 2843
  • MedDRA: -
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