Sanfilippo B disease in two related sibships. Biochemical studies in patients, parents and sibs.

In two related Sanfilippo B families, comprising 27 individuals, some biochemical parameters were studied. After detection of the patients, an attempt was made to distinguish between heterozygotes and normals. The excretion of glycosaminoglycans in the urine and N-acetyl-alpha-D-glucosaminidase activity in leukocytes and plasma were taken as parameters for the study. The determination of N-acetyl-a-D-glucosaminidase activity in plasma is considered to be the most suitable method for heterozygote detection.