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Disease definition

Histidinemia is a rare metabolic disorder characterized by elevated histidine levels in blood, urine, and cerebrospinal fluid, generally with no clinical repercussions.


Classification level: Disorder
  • Synonym(s):
    • HAL deficiency
    • HIS deficiency
    • Histidase deficiency
    • Histidine ammonia-lyase deficiency
    • Histidinuria
    • Hyperhistidinemia
  • Prevalence: 1-9 / 100 000
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Neonatal
  • ICD-10: E70.8
  • OMIM: 235800
  • UMLS: C0220992  C0268642
  • MeSH: C538320
  • GARD: 6661
  • MedDRA: -

Detailed information


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