ABSTRACT
Hurler syndrome is the classic or prototypic mucopolysaccharidosis (MPS). The molecular defect in Hurler disease is in the activity of a-L-iduronidase. The discovery of the MPS correcting factor capable of correcting the defective glycosaminoglycan catabolism in cultured cells raised the hope that these diseases might be treatable by transplantation or enzyme replacement therapy. Corneal clouding does not change; valvular disease seems to be unaltered. There is little likelihood that this approach would affect the brain; trials are underway to treat with intrathecal enzyme. Bone marrow transplantation appears not to improve the skeletal or ocular manifestations of the disease. In patients without a compatible donor, unrelated umbilical cord blood transplantation may be an option. It is possible that transplantation and enzyme replacement therapy may be complementary. Patients were selected with Hurler-Scheie or Scheie phenotypes and given enzyme intravenously weekly for as long as 62 weeks.
