glycogen storage disease type VIImedical dictionary

<disease>

An autosomal recessive muscle glycogen storage disease in which there is deficient expression of muscle phosphofructokinase activity, resulting in increased concentrations of glucose-6-phosphate and fructose-6-phosphate and low concentrations of fructose-1,6-diphosphate in muscle tissue.

Glycogen storage in muscle is increased, perhaps due to activation of glycogen synthase by accumulated glucose-6-phosphate. It has been proposed that shunting of glucose-6-phosphate and fructose-6-phosphate into the pentose phosphate pathway may result in increased synthesis of purines and pyrimidines, causing hyperuricaemia and gout.

Erythrocytes from patients may show decreased phosphofructokinase activity and 2,3-diphosphoglycerate deficiency. Exercise intolerance is present and severe congenital muscular dystrophy has been reported.

Inheritance: autosomal recessive

(12 Dec 1998)