Popis: |
Studies in three sibs from an Argentine family, aged 29, 18 and 9 years, suffering from a severe neurological disease, revealed in the two older brothers (the third died), ultrastructural changes in cellular vacuolization in diverse peripheral tissues (conjunctival, gum and skin biopsies) and in blood lymphocytes. These data were suggestive of mucopolysaccharidosis, mucolipidosis or glycoproteinosis. However, the activity of lysosomal enzymes, the excretion of mucopolysaccharides and oligosaccharides reactive to orcinol, as well as the search for aspartylglucosaminuria gave normal values. The main biochemical finding was the detection of a substantial urinary increase of a unique resorcinol-positive compound, which by thin-layer chromatography was identified as N-acetylneuraminic acid (NANA-Free) and when quantified by the thiobarbituric acid method previously passed through a gel filtration column (Sephadex G-15) or through ion exchange resins, showed a NANA-Free concentration about 15 times higher than in controls of similar age (Table 2). The ultrastructural findings (Figs. 3-5), the hypersialuria and the present clinical state of these patients (Table 1, Figs. 1, 2) were compatible with Salla disease, a rare lysosomal storage disease originally observed in Finland. The precocity and severity of the neurological damage in our patients were evident since birth and without maturing accomplishments in their first years, contrary to the progressive neurological regression described for the classical syndrome. Based on these facts we suggest that the Argentine patients would constitute a new clinical form of Salla disease. |