Mucopolysaccharidosis II
Mucopolysaccharidosis II , also known as Hunter's disease, is an inheritable metabolic disease.
The group of mucopolysaccharidoses includes diseases related to a disorder of the lysosomal degradation of mucopolysaccharides. Due to the typical inheritance (X-linked recessive), almost exclusively boys are affected by the disease.
The cause is a defect in the iduronate 2-sulfatase gene, which is required for the degradation of dermatan and heparan sulfate. As a result, accumulation of dermatan and heparan sulfate occurs, leading to dysfunction of the cells and ultimately the organs.
Depending on whether the iduronate-2-sulfatase is completely absent or only has a dysfunction, the severity of the symptoms are vary a lot. Examples include mild to severe mental retardation, cardiac involvement, heart failure, umbilical hernias, and growth retardation.
In addition, pale and nodular skin changes ("Peau d'orange") are specific for Hunter's disease.
Life expectancy is not severely limited, depending on the severity.