• Journal of The Korean Society of Inherited Metabolic disease
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• v.16 no.1
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• pp.24-33
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• 2016

Mucopolysaccharidosis type VI (MPS VI) is a rare disease caused by the mutation of ARSB with prevalence range from 1/5,000 in northeast Brazil to 1/2,057,529 births in Czech Republic. In Asia, there is only one published figure in Taiwan of about 1/833,000 births. The exact prevalence in the Korean population is unknown, but we estimated the incidence of MPS VI is about 0.03/100,000 live births. Enzyme replacement therapy (ERT) with recombinant human Arylsulfatase B (rhASB) is a modality for the treatment of MPS VI that reduces the excretion of urine glycosaminoglycan (GAG) and improves joint motion, pulmonary function, and endurance. We presented the clinical features, molecular analysis and outcome of ERT in three Korean MPS VI patients. All patients had the typical characteristic clinical features of MPS IV. Short stature, dysostosis multiplex, corneal opacity and valvular heart disease were found at first presentation, while restrictive lung disease and carpal tunnel syndrome developed later in all patients. Molecular analysis demonstrated novel missense and nonsense mutation in the patients, including p.Ile 67Ser, p.Gly328Arg, $p.Arg191^*$, p.Asp352Asn, and p.Gly17Asp. After ERT, urine GAG was decreased in all patients. Skeletal involvement, corneal opacity, heart valve abnormalities and pulmonary function were not improved with ERT, but it had a better outcome on regarding joint motion and endurance. One patient underwent allogeneic bone marrow transplantation (BMT) prior to ERT, but their clinical response was not improved much after BMT. This study demonstrates clinical phenotypes and molecular analysis of the severe form of MPS VI in Korean patients.