Glycosphingolipid levels in an unusual neurovisceral storage disease characterized by lactosylceramide galactosyl hydrolase deficiency: lactosylceramidosis.

The glycosphingolipid composition of brain and visceral tissue from a patient with an unusual neurovisceral lipid storage disease, characterized by a lactosylceramide galactosyl hydrolase deficiency, was determined. Analyses of erythrocytes, plasma, bone marrow cells, urine sediment, and liver biopsy from the patient were compared with those of normal infantile controls. Abnormally high levels of lactosylceramide (GL-2a) were found in these samples. Subsequent studies on spleen, liver, kidney, lymph nodes, and adrenal gland confirmed this finding and clearly showed that the metabolism of hematoside (Gm3) and glucosylceramide (GL-1a) was also affected. The accumulation of GL-1a and Gm3 was most pronounced in spleen, but it was not of the order seen in the spleens of patients with Gaucher's disease that were studied for comparison. Since the disease was primarily neurological in nature, fresh-frozen brain was also studied. The level of GL-2a in gray matter was equal to that of galactosylceramide (GL-1b), and elevated amounts of GL-1a, asialo-Gm2, Gm2, and Gm3 were also found; the only major abnormality in white matter was the accumulation of GL-2a and lesser amounts of the gangliosides Gm3 and Gm2. Chemical and enzymic evidence suggests the use of the term "lactosylceramidosis" for this disease.