Mucopolysaccharidosis type II, Iduronate sulfatase deficiency

Juvenile form (early-onset, severe form):

• Aggressive behavior
• Hyperactivity
• Mental function gets worse over time
• Severe mental retardation
• Spasticity

Late (mild) form:

• Mild to no mental deficiency

Both forms:

• Carpal tunnel syndrome
• Coarse features of the face
• Deafness (gets worse over time)
• Increased hair (hypertrichosis)
• Joint stiffness
• Large head (macrocephaly)

Signs of the disorder include:

• Abnormal retina (back of the eye)
• Decreased iduronate sulfatase enzyme in blood serum or cells
• Heart murmur and leaky heart valves
• Enlarged liver (hepatomegaly)
• Enlarged spleen (splenomegaly)
• Inguinal hernia
• Joint contractures
• Spasticity

Tests may include:

• Enzyme study
• Genetic testing for change (mutation) in the iduronate sulfatase gene
• Urine test for heparan sulfate and dermatan sulfate

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Hunter syndrome Overview

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Hunter syndrome Treatment

Review Date: 05/16/2011
Reviewed By: Chad Haldeman-Englert, MD, Wake Forest School of Medicine, Department of Pediatrics, Section on Medical Genetics, Winston-Salem, NC. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org)