Severe glycogen storage disease, also called glycogenosis II, is caused by deficiency of alpha-1,4-glucosidase, the lysosomal enzyme responsible for glycogen hydrolysis.
Even though the nonlysosomal glycogenolytic system is normal, glycogen still accumulates in the lysosomes in almost all tissues, but produces especially severe effects in skeletal and cardiac muscle leading to early mortality.
Specific enzyme assay in muscle cells, leukocytes or amniocytes confirms the diagnosis.
(29 Dec 1997)