If carpal tunnel syndrome develops, a further decrease in hand function can occur. The bones themselves may be affected, resulting in short stature. In addition, pebbly, ivory-colored skin lesions may be found on the upper arms, legs, and upper back of some people with it. These skin lesions are considered pathognomic for the disease. Finally, the storage of GAGs in the brain can lead to delayed development with subsequent intellectual disability and progressive loss of function.The age at onset of symptoms and the presence or absence of behavioral disturbances are predictive factors of ultimate disease severity in very young patients. Behavioral disturbances can often mimic combinations of symptoms of attention deficit hyperactivity disorder, autism, obsessive compulsive disorder, and/or sensory processing disorder, although the existence and level of symptoms differ in each affected child. They often also include a lack of an appropriate sense of danger, and aggression. The behavioral symptoms of MPS II generally precede neurodegeneration and often increase in severity until the mental handicaps become more pronounced. By the time of death, most children with severe MPS II have severe mental disabilities and are completely dependent on their caretakers. Genetics
Since Hunter syndrome is an X-linked recessive disorder, it preferentially affects male patients. The IDS gene is located on the X chromosome. The IDS gene encodes for an enzyme called iduronate-2-sulfatase (I2S). A lack of this enzyme leads to a buildup of GAGs, which cause the symptoms of MPS II.
A phase II/III clinical trial began in 2014.In 2017, a 44-year-old  patient with MPS II was treated with gene therapy in an attempt to prevent further damage by the disease. This is the first case of gene therapy being used in vivo in humans. The study was extended to six patients in 2018. Society
On 24 July 2004, Andrew Wragg, 38, of Worthing, West Sussex, England, suffocated his 10-year-old son Jacob with a pillow, because of the boys disabilities related to MPS II. A military security specialist, Wragg also claimed that he was under stress after returning from the war in Iraq. He denied murdering Jacob, but pleaded guilty to manslaughter by reason of diminished capacity. Mrs Justice Anne Rafferty called the case "exceptional", gave Wragg a two-year prison sentence for manslaughter, then suspended his sentence for two years. Rafferty said  "nothing [was] to be gained" from sending Wragg to prison for the crime. See also
Hurler syndrome (MPS I)
Sanfilippo syndrome (MPS III)
Morquio syndrome (MPS IV)
Prenatal testing
Genetic counseling

References
External links
 Media related to Hunter syndrome at Wikimedia Commons
GeneReview/NIH/UW entry on Mucopolysaccharidosis Type II