Expert Reviewed By: Dr. Brandon Colby MD
Mucopolysaccharidosis type VI (MPS VI), also known as Maroteaux-Lamy syndrome, is a rare genetic disorder that affects multiple organs and systems in the body. This article aims to provide an updated overview of MPS VI, discussing its clinical, diagnostic, and therapeutic aspects, as well as the importance of genetic testing in understanding and managing this complex condition.
Understanding Mucopolysaccharidosis Type VI
MPS VI is caused by a deficiency in the enzyme N-acetylgalactosamine 4-sulfatase (arylsulfatase B), which is responsible for breaking down large sugar molecules called glycosaminoglycans (GAGs). When GAGs accumulate in the body, they can cause damage to various organs and tissues, leading to a wide range of symptoms that may include skeletal abnormalities, joint stiffness, heart and lung problems, and vision and hearing difficulties1.
Diagnosing Mucopolysaccharidosis Type VI
The diagnosis of MPS VI typically involves a combination of clinical examination, biochemical testing, and genetic analysis. Biochemical tests can measure the activity of the deficient enzyme in blood or other body fluids, while genetic testing can confirm the presence of mutations in the ARSB gene, which is responsible for producing the enzyme1.
Genetic Testing for Definitive Diagnosis
Genetic testing plays a crucial role in the definitive diagnosis of MPS VI, especially when certain symptoms, such as corneal opacity, are present. In a case report of a 16-year-old Chinese male with MPS VI, genetic testing confirmed the presence of compound heterozygous missense mutations in the ARSB gene, emphasizing the importance of genetic testing in accurately diagnosing the condition4.
Treating Mucopolysaccharidosis Type VI
The primary treatment for MPS VI is enzyme replacement therapy (ERT) with galsulfase, a recombinant form of the deficient enzyme. ERT has been shown to improve various clinical outcomes, such as endurance, joint mobility, and growth, in patients with MPS VI2.
Long-Term Benefits of Enzyme Replacement Therapy
A case report of a Maroteaux-Lamy patient who received ERT for 15 years demonstrated significant improvements in their clinical condition compared to their elder sibling who passed away before initiating ERT. This highlights the importance of specific therapy in managing multisystemic genetic diseases like MPS VI3.
Conclusion
Mucopolysaccharidosis type VI is a rare and complex genetic disorder that requires a multidisciplinary approach for accurate diagnosis and effective management. Genetic testing plays a vital role in confirming the diagnosis and guiding treatment decisions, while enzyme replacement therapy offers significant benefits for patients with MPS VI. As our understanding of the disease continues to evolve, further advancements in diagnostic and therapeutic strategies hold promise for improving the quality of life for individuals affected by this challenging condition.
About The Expert Reviewer
Dr. Brandon Colby MD is a US physician specializing in the personalized prevention of disease through the use of genomic technologies. He’s an expert in genetic testing, genetic analysis, and precision medicine. Dr. Colby is also the Founder of and the author of Outsmart Your Genes.
Dr. Colby holds an MD from the Mount Sinai School of Medicine, an MBA from Stanford University’s Graduate School of Business, and a degree in Genetics with Honors from the University of Michigan. He is an Affiliate Specialist of the American College of Medical Genetics and Genomics (ACMG), an Associate of the American College of Preventive Medicine (ACPM), and a member of the National Society of Genetic Counselors (NSGC)