Type II Glycogenosis in Adults

To the Editor: The classic form of Type II glycogenosis with death occurring in infancy or early childhood (infantile GSD II, or Pompe's disease) exhibits intracellular glycogen accumulations surrounded by membranes, so called “abnormal lysosomes”1,2 that may be explained by the deficiency of acid α-glucosidase.3 However, this lysosomal enzyme deficiency does not explain the excessive cytoplasmic glycogen observed in infantile GSD II2 and, to a lesser extent, in the adult form of the disease. In 22 patients of 13 families with GSD II, we did not encounter adult and infantile cases in different members of the same family. In infantile.