<qa>  What is the name of the type of Glycogen Storage Disease?Glycogen Storage Disease Type II GSD-II; also known as Pompe disease is caused by a deficiency of a critical enzyme in the body called acid alpha-glucosidase GAA. Normally, GAA is used by the bodys cells to break down glycogen a stored form of sugar within specialized structures called lysosomes. In patients with GSD-II, an excessive amount of glycogen accumulates and is stored in various tissues, especially heart and skeletal muscle, which prevents their normal function. This study is being conducted to evaluate the safety and effectiveness of recombinant human acid alpha-glucosidase rhGAA as a potential enzyme replacement therapy for GSD-II. Patients diagnosed with infantile-onset GSD-II who are greater than 6 months old, but less than or equal to 36 months old will be studied. 