Type IV glycogen storage disease. Light microscopic, electron microscopic, and enzymatic study

The case of a 14 mth old Latin American girl with the diagnosis of Type IV glycogen storage disease is reported. The diagnosis was reached on the basis of the typical clinical manifestations, the light and electron microscopic findings, and the demonstration of absence of the branching enzyme α 1,4 glucan:α 1,4 glucan 6 glucosyl transferase in the liver and in the cultured skin fibroblasts.