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Carbamoyl-phosphate synthetase 1 deficiency

Disease definition

Carbamoyl-phosphate synthetase 1 deficiency (CPS1D) is a rare and severe disorder of urea cycle metabolism most commonly characterized by either a neonatal-onset of severe hyperammonemia that occurs few days after birth and manifests with lethargy, vomiting, hypothermia, seizures, coma and death or a presentation outside the newborn period at any age with (sometimes) milder symptoms of hyperammonemia.


Classification level: Disorder
  • Synonym(s):
    • CPS1 deficiency
    • CPS1D
    • Carbamoyl-phosphate synthetase I deficiency
    • Carbamoyl-phosphate synthetase deficiency
  • Prevalence: 1-9 / 1 000 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Neonatal, All ages
  • ICD-10: E72.2
  • OMIM: 237300
  • UMLS: C0751753
  • MeSH: -
  • GARD: 7269
  • MedDRA: 10058297
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