Glycogen Storage Disease Type VI

Also known as Hers disease or liver phosphorylase deficiency.

GSD VI is one of the least severe forms of GSD. In most individuals apart from liver enlargement there are few other problems. There is usually no tendency to low blood sugar, the liver becomes smaller with age and children grow normally. GSD VI has autosomal recessive inheritance.

There used to be a GSD Type VIII resulting from lack of phosphorylase-b-kinase activity; however this has now be reclassified as a subtype of GSD VI. Symptoms are relatively mild: hepatomegaly, increased liver glycogen, and decreased leukocyte phosphorylase are present. Liver shrinkage occurs in response to glucagon. It has been described as X-linked recessive.