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Glycogen storage disease due to muscle glycogen phosphorylase deficiency

Disease definition

Myophosphorylase deficiency (McArdle's disease), or glycogen storage disease type 5 (GSD5) , is a severe form of glycogen storage disease characterized by exercise intolerance.


Classification level: Disorder
  • Synonym(s):
    • GSD due to muscle glycogen phosphorylase deficiency
    • GSD type 5
    • GSD type V
    • Glycogen storage disease type 5
    • Glycogen storage disease type V
    • Glycogenosis due to muscle glycogen phosphorylase deficiency
    • Glycogenosis type 5
    • Glycogenosis type V
    • McArdle disease
    • Myophosphorylase deficiency
  • Prevalence: Unknown
  • Inheritance: Autosomal recessive 
  • Age of onset: Infancy, Childhood
  • ICD-10: E74.0
  • OMIM: 232600
  • UMLS: C0017924  C2936916
  • MeSH: C537276  D006012
  • GARD: 6528
  • MedDRA: 10018462

Detailed information

Article for general public


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