Sly Disease (Mucopolysaccharidosis Type VII)
This is a rare mucopolysaccharidosis with a very variable phenotype. There is a late onset form with skeletal dysplasia, an intermediate form with a phenotype resembling Hurler disease, with or without corneal clouding, and, probably most commonly, a very severe form that presents in the neonatal period with hydrops fetalis and dysostosis multiplex.
Enzyme Tests:
Deficiency of ß-glucuronidase is the primary defect.