Sanfilippo A syndrome in the fetus.

A family is reported in which Sanfilippo A syndrome affected three siblings: the proband and twin premature infants. The feasibility of intrauterine diagnosis of mucopolysaccharidoses (MPS) Type IIIA, was demonstrated by the excessive accumulation of 35SO4-mucopolysaccharides in fibroblasts cultured from amniotic fluid obtained by amniocentesis Cross-correction studies and enzymatic analysis of cultured skin fibroblasts from the proband and the infants revealed the absence of the MPS IIIA correction factor, heparan sulfate sulfatase. However, when the premature infants expired shortly after birth, no central nervous system histopathology or ultrastructural abnormalities were found. From these observations it would appear the the third trimester fetus with MPS type IIIA has little CNS involvement.