Two siblings, 9 and 4 1/2 years old, had alpha-L-fucosidase deficiency, angiokeratoma, progressive psychomotor retardation, neurologic signs, coarse facila features, and dysostosis multiplex. It appears that genetic heterogeneity is present in fucosidosis; there are at least two types. In type 1, patients have no vascular lesions, but have rapid psychomotor regression, severe and rapidly progressing neurologic signs, elevated sodium and chloride excretion in the sweat, and fatal outcome before the sixth year. In type 2, patients have angiokeratoma, milder psychomotor retardation and neurologic signs, longer survival, and normal salinity in the sweat. Quantitative studies on erythrocytes and in saliva disclosed severely increased expressions of Lea and Leb. Biopsies of skin and gingiva showed alterations as seen in angiokeratoma. There was also evidence of lysosomal storage in vascular endothelium, eccrine sweat gland epithelium, and fibroblasts of the skin.
