[Biochemical diagnosis of mannosidosis in 2 families].

On examination of children with primary diagnosis of mucopolysaccharidosis distinct deficiency of acid alpha-D-mannosidase was found in leukocytes of the children and decrease in the enzymatic activity down to the level of heterozygote carriers was observed in their parents. The activity of neutral alpha-D-mannosidase was within the range of normal values in the children and parents. The examination carried out enabled to establish the diagnosis the hereditary lysosomal disease of accumulation--mannosidosis--in the children.