Atypical Presentation of Mucopolysaccharidosis. Morquio's Syndrome (Type IV-B): A Morbid Entity

Mucopolysaccharidosis (MPS) are a group of metabolic disorders of the lysosomal storage disease family caused by the absence or malfunctioning of lysosomal enzymes, which blocks degradation of mucopolysaccharides and leads to abnormal accumulation of heparan sulfate, dermatan sulfate, and keratan sulfate. Morquio's syndrome is a rare autosomal-recessive mucopolysaccharidosis. This syndrome is characterized by a reduced activity of N-acetylgalactosamine-6-sulfate-sulfatase (type A), or beta-galactosidase (type B). This deficiency leads to a lysosomal storage disease with accumulation of keratan sulfate and chondroitin-6-sulfate in connective tissue, skeletal system and teeth. The general phenotype includes coarse facies, corneal clouding, hepatosplenomegaly, joint stiffness, hernias, dysostosis multiplex, lower limb alignment problems, mucopolysaccharides excretion in the urine and metachromatic staining in peripheral leukocytes and bone marrow. Consequently, aortic valvular disease, gastrointestinal disease and dental abnormalities occur. Clinical manifestations of mucopolysaccharidosis depend on the type of disease. We report a case of morquio's syndrome in a child, solely diagnosed on the basis of history and physical examination of the case reported. The clinical features and complications of the case and review of the literature are discussed.