Urine analysis in the diagnosis of mucopolysaccharide disorders.

Abstract

The mucopolysaccharidoses are a rare group of inherited disorders of connective tissue metabolism characterized by the storage of sulphated mucopolysaccharides (MPS). The phenotypic features are often apparent early in life: dysmorphic or coarse facial features, hirsutism, skeletal abnormalities, joint stiffness and developmental delay. Inheritance is autosomal recessive except for Hunter syndrome which is Xlinked. The first clinical description of patients with MPS diseases was made in 1917 by Charles Hunter.' He described two male siblings with a unique facial appearance (gargoylism), hepatosplenomegaly, short stature, deafness, heart disease and joint stiffness. In 1919 Gertrude H urler? described two unrelated male patients with the same features but with the addition of corneal clouding and mental retardation. These disorders became known as mucopolysaccharidoses in 1952 following the discovery by Brante' of the presence of chondroitin sulphate-like substances stored in the liver and meninges of a Hurler patient. In 1957 Dorfman and Lorincz reported increased excretion of MPS or glycosaminoglycans (GAGs) in the urine of patients suffering from a mucopolysaccharidosis. This proved to be of great diagnostic importance and led to the development of urine screening tests for the mucopolysaccharidoses. The type and ratio of the urinary MPS were found to be indicative of the subclass of MPS disease present. The mucopolysaccharidoses were shown to be lysosomal storage diseases by Van Hoof and