glycogen storage disease IXd

A glycogen storage disease IX that is characterized by X-linked inheritance of variable exercise-induced muscle weakness or stiffness that has_material_basis_in mutation in the PHKA1 gene on chromosome Xq13.

Signs and symptoms

• Elevated circulating creatine kinase activity
• Quadriceps muscle weakness
• Reduced muscle phosphorylase kinase activity
• Distal amyotrophy
• Glycogen accumulation in muscle fiber lysosomes
• Distal muscle weakness
• Increased muscle glycogen content
• Lower limb muscle weakness
• Pelvic girdle muscle weakness
• Hypoglycemia

Also known as: GSD IXd; GSD due to muscle phosphorylase kinase deficiency; GSD type 9D; GSD type 9E; GSD type IXd