Glycogen storage disease

Class	Defect	Clinical Clues	Diagnosis	Therapy
GSD 0a	Glycogen synthase 2 deficiency in liver	Ketotic hypoglycemia No hepatomegaly	Liver biopsy and enzyme testing DNA testing	Uncooked cornstarch Commercial glucose polymers (eg, Glycosade) Liver transplantation
GSD 0b	muscle glycogen synthase deficiency	Cardiomyopathy Exercise intolerance Weakness	Muscle biopsy (glycogen depletion) Enzyme assay DNA testing	No specific treatment
GSD Ia (von Gierke disease)	glucose-6-phosphatase deficiency	Ketotic hypoglycemia Hepatomegaly	DNA testing Liver biopsy Enzyme assay	Uncooked cornstarch Allopurinol Granulocyte colony-stimulating factor (G-CSF) Commercial glucose polymers (eg, Glycosade) Liver transplantation
GSD Ib	q transport defect
GSD II (Pompe disease)	lysosomal acid maltase deficiency	Hypotonia Muscle weakness Hypertrophic cardiomyopathy Rhabdomyolysis	Fibroblast, leukocyte, muscle, or liver enzyme assay DNA testing	Enzyme replacement therapy Commercial glucose polymers (eg, Glycosade) Liver transplantation
GSD IIb (Danon disease)	lysosome-associated membrane protein 2 (LAMP2) deficiency	Hypotonia Hypertrophic cardiomyopathy Rhabdomyolysis	Muscle biopsy DNA testing	No specific treatment
GSD III	glycogen debrancher deficiency	Ketotic hypoglycemia Hepatomegaly	Fibroblast or liver enzyme assay DNA testing	Uncooked cornstarch Commercial glucose polymers (eg, Glycosade) Liver transplantation
GSD IV	glycogen branching enzyme deficiency	Hepatomegaly Cirrhosis Rare neuromuscular presentations, such as fetal akinesia sequence, myopathy, axonal neuropathy, adult polyglucosan body disease	Fibroblast, muscle, or liver biopsy DNA testing	Commercial glucose polymers (eg, Glycosade) Liver transplantation
GSD V (McArdle disease)	muscle phosphorylase deficiency	Fatigability Myoglobinuria Rhabdomyolysis	Muscle biopsy Muscle enzyme assay DNA testing	Sucrose prior to exercise
GSD VI (Hers disease)	liver phosphorylase deficiency	Hepatomegaly Mild hypoglycemia	Liver biopsy and enzyme assay DNA testing	Commercial glucose polymers (eg, Glycosade) Liver transplantation
GSD VII (Tarui disease)	phosphofructokinase deficiency in muscle	Fatigability Myoglobinuria Rhabdomyolysis	Muscle enzyme assay DNA testing	No specific treatment
Phosphoglycerate kinase deficiency	phosphoglycerate kinase deficiency	Hemolysis Fatigability Myoglobinuria CNS dysfunction Rhabdomyolysis	Muscle/RBC enzyme assay DNA testing	Bone marrow transplantation
GSD IX	phosphorylase kinase deficiency	Hepatomegaly Mild hypoglycemia Fatigability Exercise intolerance	Liver/muscle biopsy Enzyme assay DNA testing	Commercial glucose polymers (eg, Glycosade) Liver transplantation
GSD IXa1 (GSD VII)	alpha-2 subunit defect in liver
GSD IXb	beta subunit defect in liver
GSDIXc	gamma subunit defect in liver and muscle
GSD IXd	alpha subunit defect in muscle
GSD X	phosphoglycerate mutase deficiency	Fatigability Myoglobinuria Exercise intolerance Rhabdomyolysis	Muscle biopsy and enzyme assay DNA testing	No specific treatment
GSD XI	lactate dehydrogenase A (LDHA) deficiency and lactate dehudogenase B (LDHB) deficiency	Fatigability Myoglobinuria Rhabdomyolysis	Muscle or RBC enzyme assay DNA testing	No specific treatment
Fanconi-Bickel syndrome	GLUT2 deficiency	Growth retardation Renal Fanconi syndrome Galactosemia	Clinical features DNA testing	Frequent, small meals Uncooked cornstarch or nocturnal enteral nutrition Electrolytes, carnitine, and vitamin D as needed Restriction of galactose
GSD XII	aldolase A deficiency	Hemolysis Jaundice Myoglobinuria Muscle weakness Fatigability Rhabdomyolysis	Muscle or RBC enzyme assay DNA testing	No specific treatment
GSD XIII	beta-enolase deficiency in muscle	Exercise intolerance Increased CPK Rhabdomyolysis	Muscle biopsy Enzyme assay DNA testing	No specific treatment
GSD XIV	phosphoglucomutase 1 deficiency in muscle	Exercise intolerance Myoglobinuria Increased CPK Rhabdomyolysis Myoglobinuria	Muscle biopsy Enzyme assay DNA testing	No specific treatment
GSD XV	glycogenin 1 deficiency in muscle	Muscle weakness Arrhythmias	Muscle biopsy (glycogen depletion) DNA testing	No specific treatment