Glycogen storage disease type I: laboratory data and diagnosis.

A study of 20 cases of glycogen storage disease type I has shown differences from the classical picture. Hyperuricemia was observed in fewer than half of the cases. All patients had increased triglycerides in serum, but fewer than two thirds had increased concentrations of total cholesterol. There was a consistent increase of aminotransferases in serum. Many textbooks discuss hyperuricemia, lactic acidemia, and lipidemia in this disease without mentioning aminotransferases, and above-normal values for these enzymes ought to be given consideration, to avoid misdiagnosis. Glycogen storage disease type IB was detected by comparing glucose-6-phosphatase (EC 3.1.3.9) activity in frozen and unfrozen portions of the same liver biopsy. Latent activity, which appeared after freezing, increased the total activity to within the normal range (4.7-9.1 mumol/min per gram of tissue, wet weight) in type IB, but not in type IA.