The clinical features of this child neurologic involvement, hepatosplenomegaly, and accumulation of foamy macrophages - suggest a lysosomal storage disorder. One such disorder, with which the clinical history is quite compatible, is Niemann-Pick disease type A. It is characterized by lysosomal accumulation of sphingomyelin owing to a severe deficiency of sphingomyelinase. Globules of a1 -antitrypsin are seen in the liver cells of individuals with inherited deficiency of a1 -antitrypsin. The glycogen storage disease known as von Gierke disease results from glucose-6-phosphatase deficiency. In familial hypercholesterolemia, there are fewer LDL receptors on hepatocytes, leading to early and accelerated atherosclerosis by young adulthood. Collagen synthesis is impaired in individuals with Ehlers-Danlos syndrome.