How is acid maltase deficiency diagnosed and treated?
CK level is usually mildly elevated (2 to 10 times normal).
The EMG shows abundant complex repetitive discharges, myopathic changes, and spontaneous activity, including myotonia, especially in thoracic paraspinal muscles.
Characteristic findings on muscle biopsy are those of a vacuolar myopathy.
For definite diagnosis, enzyme activity is first measured in dried blood spots, followed by confirmatory testing of acid maltase activity in cultures of fibroblasts, muscle tissue, or by genetic testing.
Enzyme replacement therapy with recombinant alpha-glucosidase has shown significant clinical response in infantile form and modest response in juvenile and adult forms.
