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Argininosuccinic aciduria

Disease definition

A rare, genetic disorder of urea cycle metabolism typically characterized by either a severe, neonatal-onset form that manifests with hyperammonemia accompanied with vomiting, hypothermia, lethargy and poor feeding in the first few days of life, or late-onset forms that manifest with stress- or infection-induced episodic hyperammonemia or, in some, behavioral abnormalities and/or learning disabilities, or chronic liver disease. Patients often manifest liver dysfunction.


Classification level: Disorder
  • Synonym(s):
    • ASA deficiency
    • ASL deficiency
    • Argininosuccinase deficiency
    • Argininosuccinatelyase deficiency
    • Argininosuccinic acid lyase deficiency
  • Prevalence: 1-9 / 100 000
  • Inheritance: Autosomal recessive 
  • Age of onset: All ages
  • ICD-10: E72.2
  • ICD-11: 5C50.A0
  • OMIM: 207900
  • UMLS: C0268547
  • MeSH: D056807
  • GARD: 5843
  • MedDRA: 10058299

Detailed information

General public


Disease review articles

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