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Class I glucose-6-phosphate dehydrogenase deficiency

Disease definition

A rare constitutional hemolytic anemia characterized in symptomatic forms by mild to severe chronic hemolysis, which is further exacerbated by oxidative stress and may lead to chronic non-shperocytic hemolytic anemia of variable severity. Variation in glucose-6-phosphate dehydrogenase levels accounts for differences in sensitivity to oxidants, with chronic hemolysis occurring in association with very low enzyme levels, while the majority of affected individuals remain asymptomatic. The most common clinical manifestations are neonatal jaundice and signs and symptoms of acute hemolysis (such as fatigue, back pain, anemia, and jaundice).


Classification level: Disorder
  • Synonym(s):
    • Class I G6PD deficiency
    • Severe hemolytic anemia due to G6PD deficiency
  • Prevalence: <1 / 1 000 000
  • Inheritance: X-linked recessive 
  • Age of onset: Neonatal
  • ICD-10: D55.0
  • OMIM: 300908
  • UMLS: -
  • MeSH: -
  • GARD: -
  • MedDRA: -

Detailed information


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