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Hyperammonemia due to N-acetylglutamate synthase deficiency

Disease definition

A rare disorder of urea cycle metabolism causing a deficit of ammonia detoxification and arginine synthesis, and characterized by hyperammonemia of variable severity. Manifestations range from neonatal presentation of poor feeding, vomiting, lethargy, tachypnea, convulsions and coma to adult-onset headaches, hazy gastrointestinal symptoms, seizures, behavioral/psychiatric problems, confusion and lethargy.


Classification level: Disorder
  • Synonym(s):
    • NAGS deficiency
  • Prevalence: <1 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: All ages
  • ICD-10: E72.2
  • OMIM: 237310
  • UMLS: C0268543
  • MeSH: -
  • GARD: 7158
  • MedDRA: -
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