Biochemical investigation of an unusual case of glycogenosis

Abstract

An unusual case of combined glycogenosis with muscle limit dextrinosis, myopathy, and defective liver glucose-6-phosphatase (G-6-Pase) is described. The clinical symptoms resembled those of McArdle's syndrome, except that the onset of the disease occurred at an early age and the patient lacked sustained muscle contracture after prolonged exercise. The patient's muscle phosphorylase and glycolytic apparatus were normal except for an amylo-1-6-glucosidase deficiency, whereas the defect in McArdle's syndrome is a deficiency in muscle phosphorylase. The patient's restricted exercise tolerance did not improve even when muscle cell glycolysis was experimentally increased. An unusual case of combined glycogenosis with muscle limit dextrinosis, myopathy, and defective liver glucose-6-phosphatase (G-6-Pase) is described. The clinical symptoms resembled those of McArdle's syndrome, except that the onset of the disease occurred at an early age and the patient lacked sustained muscle contracture after prolonged exercise. The patient's muscle phosphorylase and glycolytic apparatus were normal except for an amylo-1-6-glucosidase deficiency, whereas the defect in McArdle's syndrome is a deficiency in muscle phosphorylase. The patient's restricted exercise tolerance did not improve even when muscle cell glycolysis was experimentally increased.