Mucopolysaccharidosis IV A

Mucopolysaccharidosis IV A is a congenital metabolic disorder of mucopolysaccharides and is one of the lysosomal storage diseases.

In the most common type A, there is a deficiency or deficiency of the enzyme N-acetyl-galactosamine-6-sulfate sulfatase, which is responsible for the degradation of the mucopolysaccharide keratan sulfate.

In the much rarer type B is a beta-galactosidase deficiency. Both forms are inherited autosomal recessive. This enzyme deficiency leads to increased storage of non-degradable mucopolysaccharides in healthy cells and organs. In the course of the disease, the function of the cell and ultimately the organs, decrease.

The disease manifests itself mainly in appearance, and patients suffer from short stature, deformity and malpositioning of the skeleton, and facial expression changes. In addition, patients suffer from hypermobility of the joints and ligaments and thus in-depth joint pain. 

In addition, also a increased risk of hernias, respiratory tract infections, deafness, sleep apnea and other symptoms occur. Depending on the severity, the first symptoms may appear in infancy or adulthood.

The severity of the disease increases with age.