Maroteaux-Lamy (MPS VI) is a lysosomal storage disorder caused by a deficiency of the enzyme arylsulfatase B. This deficiency leads to an accumulation of cellular carbohydrates called glycosaminoglycans (GAG) within the lysosomes of cells in the bones, joints, heart, liver and spleen and other tissues. Individuals with MPS VI typically have normal intelligence but can have significant bone deformities (dysostosis multiplex), limited range of motion, enlarged liver and spleen, cardiac and valvular disease and many other organ complications. There is a wide spectrum of disease severity and progression. There is now an FDA-approved enzyme replacement therapy for the primary treatment of MPS VI.