ORPHA:13
6-pyruvoyl-tetrahydropterin synthase deficiency
Also called Hyperphenylalaninemia due to 6-pyruvoyltetrahydropterin synthase deficiency
- Body system
- Inborn errors of metabolism
- Inheritance pattern
- Autosomal recessive
- Typical age of onset
- Infancy, Neonatal
- Estimated prevalence
- Unknown (Worldwide)
- Rarity class
- Unknown
About this disease
A rare form of hyperphenylalaninemia due to tetrahydropterin (BH4) biosynthesis deficiency, leading to central dopamine and serotonin deficiency, and characterized by infantile-onset neurological disease of variable severity ranging from mild forms with normal neurological development to severe forms with hypotonia, developmental delay, complex movement disorder dominated by dystonia or dystonia parkinsonism.
Definition from Orphanet.
Common signs
- Hypotonia
- Opisthotonus
- Hyperreflexia
- Dysphagia
- Rigidity
- Bradykinesia
Learn more
Source: Orphanet (Orphadata), ORPHA:13. Data release 2026-06-23. www.orphadata.com — CC BY 4.0.