Difficulties in diagnosing slowly progressive mucopolysaccharidosis VI: A case series

We describe the cases of two adult sisters recently diagnosed with the attenuated form of mucopolysaccharidosis VI (MPS VI, Maroteaux-Lamy syndrome). MPS VI is a rare, clinically heterogeneous lysosomal storage disorder that is characterized by a deficiency in the glycosaminoglycan-degrading enzyme arylsulfatase B. Both cases had been misdiagnosed for over 30 years despite the presence of several characteristics of the disease, including short stature (mild), coarse facial features, skeletal dysmorphisms, carpal tunnel syndrome, heart valve disease, and spinal cord compression, which together are suggestive of a lysosomal storage disease. Awareness about the clinical features of MPS VI should be communicated amongst treating neurologists, rheumatologists and other specialists who are involved in the healthcare decisions of these patients with presenting symptoms, so they can refer them to specialized centers for proper diagnosis and treatment.