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Ornithine transcarbamylase deficiency

Disease definition

A rare, genetic disorder of urea cycle metabolism and ammonia detoxification characterized by either a severe, neonatal-onset disease found mainly in males, or later-onset (partial) forms of the disease. Both present with episodes of hyperammonemia that can be fatal and which can lead to neurological sequelae.


Classification level: Disorder
  • Synonym(s):
    • OCT deficiency
    • OTC deficiency
    • Ornithine carbamoyltransferase deficiency
  • Prevalence: 1-9 / 100 000
  • Inheritance: X-linked recessive 
  • Age of onset: All ages
  • ICD-10: E72.4
  • OMIM: 311250
  • UMLS: C0268542
  • MeSH: D020163
  • GARD: 8391
  • MedDRA: 10052450
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