source: National Organization for Rare Disorders, Inc.
Maroteaux-Lamy syndrome (mucopolysaccharidosis type VI; MPS VI) is a rare genetic disorder characterized by complete or partial lack of activity of the enzyme arylsulfatase B (also called N-acetylgalactosamine-4-sulfatase), encoded by the ARSB gene. Deficiency or absence of this enzyme activity leads to the accumulation of complex carbohydrates called glycosaminoglycans (previously known as mucopolysaccharides) in the body. Abnormal accumulation of mucopolysaccharides leads to progressive involvement of multiple organ systems. The symptoms and severity of Maroteaux-Lamy syndrome can vary dramatically from one person to another; some individuals only develop mild symptoms, while others develop severe, even life-threatening complications.
Common symptoms can include coarse facial features, corneal clouding, joint abnormalities, various skeletal malformations, an abnormally enlarged liver and/or spleen (hepatosplenomegaly), and hearing loss. Cardiac disease and restrictive pulmonary disease can also occur. Intelligence is usually not affected. In 2005, the Food and Drug Administration (FDA) approved the enzyme replacement therapy known as Naglazyme® for the treatment of Maroteaux-Lamy syndrome. Maroteaux-Lamy syndrome occurs due to mutations in the ARSB gene and is inherited as an autosomal recessive disorder.