Studies in Metachromatic Leukodystrophy

Abstract

Multiple sulfatase deficiency form of metachromatic leukodystrophy (MSD-MLD) occurred in a young boy. In blood smears, leukocyte Alder-Reilly granulation abnormality aided diagnosis. Abnormal granules persisted in neutrophils in tissue culture, suggesting metabolic error intrinsic to the leukocytes. Normal eosinophil granules, originally absent, tended first to appear only in tissue culture. Autopsy tissues showed multiple deficiencies of arylsulfatases A, B, and C. Recent chemical analyses of brain showed increased dermatan sulfate; this, along with deficient sulfatase B activity, also occurs in mucopolysaccharidosis type VI. Sulfatase B deficiency may imply an O-sulfatase deficiency which could explain increased O-sulfated molecules in MSD-MLD. Family pedigree was consistent with autosomal recessive inheritance. Sulfatase A deficiency appears to be related to a qualitative change in sulfatase A enzyme itself. The same type of molecular error may also be present in sulfatases B and C.