LYSOSOMAL GLYCOGEN-STORAGE-DISEASE WITH NORMAL ACID MALTASE WITH EARLY FATAL OUTCOME

In a male infant who had cardiomyopathy, generalized muscle weakness a nd increased serum creatine kinase levels, his muscle biopsy revealed myopathic changes with tiny intracytoplasmic vacuoles containing PAS-p ositive material and high acid phosphatase activity, but had normal ac id maltase activity biochemically. These findings were consistent with those seen in lysosomal glycogen storage disease with normal acid mal tase (Danon disease). Sarcolemmal indentations commonly seen in this d isease were missing, but a complement membrane attack complex, C5b-9 w as positive along the surface membrane of the muscle fibers as seen in X-linked vacuolar myopathy. The patient was on a respirator and died at 27 months of age from pneumonia and hypertrophic cardiomyopathy. Ly sosomal glycogen storage disease with normal acid maltase may be manif ested at birth with marked skeletal and cardiac involvement leading to death in early infancy. (C) 1998 Elsevier Science B.V. All rights res erved.