Oral loading of glucose, galactose, or fructose results in a marked rise in blood lactate. Definitive diagnosis requires a liver biopsy for microscopic analysis and enzyme assay. Evidence of increased fat accumulation in the liver may be observed, similar to other forms of glycogen storage disease. Electron microscopic analysis of liver sections shows normal glycogen structure. Muscle glycogen stores are normal.
Management includes nutritional management and avoidance of fasting hypoglycemia.
Refer the patient to a dietitian experienced with GSD and the management of disorders with increased risk of hypoglycemic episodes. Refer the family of the affected child to a medical geneticist or genetic counselor to review the inheritance of GSD-0. Determine the degree of dietary intervention for each patient and follow carefully to ensure adequate prevention of fasting hypoglycemia and to provide adequate calories and protein for growth. Recommend avoidance of highly processed carbohydrates to avoid conversion of excess glucose into lactate. Activity restrictions are not indicated.