Arylsulfatases A and B in leukocytes: a comparative statistical study of late infantile and juvenile forms of metachromatic leukodystrophy and controls.

We report a statistical study on the level of aryl-sulfatases A and B in leukocytes of 106 controls, 19 cases of metachromatic leukodystrophy (MLD) infantile and juvenile forms and 25 obligate heterozygotes for MLD. Arylsulfatase A has been found to be similarly deficient in patients of the two forms. Half of the mean of the controls have been found in both types for heterozygotes. Arylsulfatase B (ASB) is slightly higher than normal in late infantile MLD although it is not statistically significant. In the 5 cases of the juvenile forms that were examined, ASB was found to be significantly reduced. This enzyme may play a role in relation to the onset of the disease.