Asymptomatic decreased activities of hepatic glucose-6-phosphatase and glycogen phosphorylase in a number of children with chronic liver disease.

The evaluation of hepatic degradation of glycogen in patients with different chronic liver diseases was carried out on the basis of: a) specific activities of hepatic enzymes involved in catabolism of glycogen; b) level of glycogen in liver biopsies; c) concentration of glucose and cAMP in serum after the intravenous administration of glucagon. In 13 out of 35 patients investigated the activity of glucose-6-phosphatase was decreased to 14-50% of the control value. In the livers of 3 patients glycogen phosphorylase activity was decreased to 10% of the control value. In patients with the significantly low activities of hepatic glucose-6-phosphatase and phosphorylase a, however, normal catabolism of glycogen in the liver was observed, neither hypoglycemia nor abnormal glycogen storage in liver biopsies nor abnormal response to glucagon being found. In the group of patients with decreased and normal activities of glucose-6-phosphatase and phosphorylase a, biochemical parameters in the serum (i.e. markers of liver damage) were not detectable. Possible causes of the selective and asymptomatic decrease in the activities of glucose-6-phosphatase and phosphorylase a are discussed.