Metabolic myopathies

Metabolic myopathies are a diverse group of inherited muscle diseases that share in common enzymatic defects that affect skeletal muscle function, typically involving energy-generating pathways. Subcategories of metabolic myopathies include abnormalities of glycogen, lipids, purine, or mitochondrial biochemistry. Glycogen storage diseases (abbreviated GSDs and also known as glycogenoses) are a major subcategory, many but not all of which have prominent muscle manifestations. Classic glycogen storage diseases include GSD II, more commonly referred to as Pompe disease, due to acid maltase deficiency, and GSD V, more commonly referred to as McArdle disease, due to myophosphorylase deficiency.