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GTR Home > Conditions/Phenotypes > Glycogen storage disease, type V

Glycogen storage disease, type V

Synonyms
GSD 5; Glycogen storage disease type 5; McArdle disease; McArdle type glycogen storage disease; Muscle glycogen phosphorylase deficiency; Myophosphorylase deficiency
Modes of inheritance
Autosomal recessive inheritance (Orphanet)

Summary

Excerpted from the GeneReview: Glycogen Storage Disease Type V
Glycogen storage disease type V (GSDV, McArdle disease) is a metabolic myopathy characterized by exercise intolerance manifested by rapid fatigue, myalgia, and cramps in exercising muscles. Symptoms are usually precipitated by isometric exercise or sustained aerobic exercise. Most individuals improve their exercise tolerance by exploiting the "second-wind" phenomenon with relief of myalgia and fatigue after a few minutes of rest. Age of onset is frequently in the first decade of life but can vary; however, diagnosis is typically delayed as myalgia and fatigability are dismissed/overlooked. Fixed muscle weakness occurs in approximately 25% of affected individuals, is more likely to involve proximal muscles, and is more common in individuals of advanced age. Approximately 50% of affected individuals have recurrent episodes of myoglobinuria that can – on occasion – eventually result in acute renal failure.
Full text of GeneReview (by section):
Summary
Diagnosis
Clinical Characteristics
Genetically Related (Allelic) Disorders
Differential Diagnosis
Management
Genetic Counseling
Resources
Molecular Genetics
Chapter Notes
References
Authors:
Miguel A Martín
Alejandro Lucia
Joaquin Arenas
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Available tests

88 tests are in the database for this condition.

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Clinical tests (88 available)

Biochemical Genetics Tests

Molecular Genetics Tests

Genes See tests for all associated and related genes

  • Also known as: GSD5, PYGM
    Summary: glycogen phosphorylase, muscle associated

Clinical features

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Imported from Human Phenotype Ontology (HPO)

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