[Case of mucolipidosis type I with a primary alpha-D-neuraminidase deficiency]

The authors describe a case of mucolipidosis I, the 9th reported in the world literature. The diagnosis was suspected in a 5 year old boy, from the appearance of hurler-like facial features. Lumbar kyphosis, dysostosis multiplex, cherry-red macular spot and foam cells in the bone marrow and it was confirmed by the characteristic oligosacchariduria (on thin layer chromatography) and excess sialic acid in cultured fibroblasts which also showed profoundly diminished activity of alpha D Neuraminidase (on two substrates - N-acetyl-Neuramin Lactose and 4 Methyl umbelliferyl N-acetyl-Neuraminide). The parents had intermediate enzyme activities, suggesting heterozygotism. After a review of the literature, the authors attempt to define the place of mucolipidosis I in the sialidoses.