From Wikipedia:

Glycogen storage disease type II (also called Pompe disease /ˈpɒmpə/ or acid maltase deficiency) is an autosomal recessive metabolic disorder^[1] which damages muscle and nerve cells throughout the body. It is caused by an accumulation of glycogen in the lysosome due to deficiency of the lysosomal acid alpha-glucosidase enzyme. It is the only glycogen storage disease with a defect in lysosomal metabolism, and the first glycogen storage disease to be identified, in 1932 by the Dutch pathologist J. C. Pompe.

The build-up of glycogen causes progressive muscle weakness (myopathy) throughout the body and affects various body tissues, particularly in the heart, skeletal muscles, liver and nervous system.

See Wikipedia for classification, signs & symptoms, diagnosis, cause, treatment, prognosis, epidemiology and history.

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