MaroteauxLamy

Maroteaux-Lamy syndrome, also known as mucopolysaccharidosis type VI (MPS VI), is a rare lysosomal storage disorder caused by deficiency of the enzyme arylsulfatase B, leading to accumulation of dermatan sulfate in tissues and organs. It is inherited in an autosomal recessive pattern. Mutations in the ARSB gene on chromosome 5 disrupt enzyme activity; carrier rates vary among populations.

Clinical features include characteristic skeletal abnormalities (dysostosis multiplex), short stature, joint stiffness and contractures, scoliosis or kyphosis, and facial coarsening. Organomegaly (hepatosplenomegaly), airway obstruction, recurrent respiratory infections, and hearing loss are common. Corneal clouding is frequent. Cardiorespiratory involvement, including valvular disease, reduces life expectancy. Intellectual development is usually preserved, though developmental delay can occur in severe cases.

Diagnosis relies on clinical features and elevated urinary dermatan sulfate and keratan sulfate. Confirmation is by measuring ARSB enzyme activity in leukocytes or cultured fibroblasts and by genetic testing for ARSB mutations. Radiographs show dysostosis multiplex with bullet-shaped metacarpals and oar-shaped ribs.

Management centers on enzyme replacement therapy with galsulfase to slow progression, particularly of somatic symptoms; treatment does not fully reverse established skeletal disease. Supportive care includes orthopedic procedures, cardiac management, respiratory support, and physical therapy. Early initiation improves outcomes. The prognosis depends on severity and access to therapy, with many patients requiring multidisciplinary, long-term care. The syndrome is named after the French physicians who described it.