Two cases of mucopolysaccharidosis type III (Sanfilippo). A biochemical study.

The mucopolysaccharide and lipid composition of human nervous tissue and viscera from one case of Sanfilippo disease type A and one case of Sanfilippo disease type C, were investigated. In the brain a moderate increase of acid glycosaminoglycans occurred. This phenomenon was much more pronounced in the viscera, especially in the liver. In all tissues this increase was mainly due to an accumulation of heparan sulphate. Changes in lipid composition were noted, but can be regarded as secondary effects. The biochemical results reported also suggest some general conclusions. (a) AGAG and lipid analyses do not permit differentiation between the subtypes of Sanfilippo disease. (b) The differences in lipid composition can probably be considered as consequences of variation in secondary effects. (c) The severe demyelination in brain correlates well with the biochemical lipid analysis. However, in other instances it remains difficult to bridge the gap still existing between some morphological and biochemical data.