Hunter syndrome

Alternative Names

Mucopolysaccharidosis type II, Iduronate sulfatase deficiency

Definition of Hunter syndrome

Hunter syndrome is an inherited disease in which long chains of sugar molecules (mucopolysaccharides) are not broken down correctly and build up in the body.

Causes, incidence, and risk factors

Hunter syndrome is an inherited condition. Boys are most often affected.


Juvenile form (early-onset, severe form):

Signs and tests

Signs of the disorder include:


The U.S. Food and Drug Administration has approved the first treatment for Hunter syndrome. The medicine, called idursulfase (Elaprase), is given through a vein (intravenously). Talk to your doctor for more information.

Expectations (prognosis)

People with the early-onset (severe) form usually live for 10 – 20 years. People with the late-onset (mild) form usually live 20 – 60 years.


Chad Haldeman-Englert, MD, Division of Human Genetics, Children’s Hospital of Philadelphia, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc. – 4/15/2009

ADAM Medical Encyclopedia

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