This is the report of a five-month-old child presenting clinical evidence of Pompe's disease: severe hypotonicity, hyporeflexia and congestive heart failure. The ECG showed a short PR interval, the chest radiography disclosed marked cardiomegaly, and the echocardiogram revealed marked left ventricular hypertrophy - the most typical finding of this disease. A skeletal muscle biopsy led to final diagnosis, because in the histopathologic study marked increased glycogen accumulation was evident. Death occurred two months after symptom onset.
