Idursulfase is used to treat some of the symptoms of a genetic condition called Hunter’s syndrome, also called mucopolysaccharidosis (MYOO-koe-pol-ee-SAK-a-rye-DOE-sis). Hunter syndrome is a metabolic disorder in which the body lacks the enzyme needed to break down certain sugars and proteins. These substances can build up in the body, causing enlarged organs, abnormal bone structure, changes in facial features, breathing problems, heart problems, vision loss, and changes in mental or physical...