Hunter syndrome, also known as mucopolysaccharidosis type II (MPS II) is a rare genetic disease almost exclusively affecting boys. Hunter syndrome is one of a number of lysosomal storage diseases (LSDs). It is estimated that the condition is present in 1 in 162 000 live births.
Hunter syndrome can affect any part of the body and causes a number of signs and symptoms. In the majority of people with Hunter syndrome, the signs and symptoms present between the ages of 2 and 4 years.
Many of the signs and symptoms are common childhood complaints, and it is the combination of them that may indicate Hunter syndrome. The symptoms of Hunter syndrome are different in each person, so there is no single typical patient experience.

