Fasting glycogen storage diseases

Other investigators have also differentiated the two activities. The apparent absence of transferase but not glucosidase activity has been proposed as a subclass of type III glycogen storage disease (37). Exposure of the enzyme to guanidine inhibited glucosidase activity on "fast B5" to a greater extent than the combined activity on "63-a-maltotriosylmaltotetraose"... 

QUESTION 8.6 Patients with Von Gierke s disease (a glycogen storage disease) lack glucose-6-phosphatase activity. Two prominent symptoms of this disorder are fasting hypoglycemia and lactic acidosis. Can you explain why these symptoms occur ... 

Glycogen storage diseases that also affect gluconeogenesis cause severe lactic acidosis on fasting. 

Glycogen storage disease types la and lb (GSD-1) are characterized by fasting hypoglycemia and elevated lactic acid, uric acid, cholesterol, and triglycerides. Patients with GSD type lb are also at risk of neutropenia and inflammatory bowel disease. 

Correia CE, et al. Use of modified cornstarch therapy to extend fasting in glycogen storage disease types la and Ib. Am J Clin Nntr. 2008 88(5) 1272-6. 

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