Hunter syndrome is a rare genetic disorder that occurs when an enzyme your body needs is either missing or doesn't work properly.
Because the body doesn't have enough of the enzyme to break down certain complex molecules, the molecules build up in harmful amounts in certain cells and tissues. The buildup that occurs in Hunter syndrome eventually causes permanent, progressive damage affecting appearance, mental development, organ function and physical abilities.
Hunter syndrome appears in children as young as 18 months. It nearly always occurs in males.
There's no cure for Hunter syndrome. Treatment of Hunter syndrome involves management of symptoms and complications.