Gaucher's disease in the presence of normal glucocerebrosidase activity

We encountered an infant with clinical and histopathologic features of Gaucher's disease (infantile, type 2) with normal glucocerebrosidase (d-glucosyl-N-acylsphingosine glucohydrolase, E.C.3.2.1.45) activity. Biochemical analysis was performed on leukocytes, cultured skin fibroblasts, and liver. Normal activity of glucocerebrosidase previously has been reported in an older child with juvenile onset (type 3) Gaucher's disease and attributed to a deficiency of a sphingolipid activator protein. These rare cases illustrate and expand our concept of Gaucher's disease and may have both diagnostic and therapeutic implications.