Alternative Names
Alpha-L-iduronate deficiency; Mucopolysaccharidosis type I; MPS I H
Definition of Hurler syndrome
Hurler syndrome is a rare, inherited disease of metabolism in which a person cannot break down long chains of sugar molecules called glycosaminoglycans (formerly called mucopolysaccharides).
Causes, incidence, and risk factors
Persons with Hurler syndrome do not make a substance called lysosomal alpha-L-iduronidase. This substance, called an enzyme, helps break down long chains of sugar molecules called glycosaminoglycans (formerly called mucopolysaccharides). These molecules are found throughout the body, often in mucus and in fluid around the joints.
Symptoms
Symptoms of Hurler syndrome most often appear between ages 3 and 8. Infants with severe Hurler syndrome appear normal at birth. Facial symptoms may become more noticeable during the first 2 years of life.
Treatment
Enzyme replacement therapy adds a working form of the missing enzyme to the body.
Expectations (prognosis)
Hurler syndrome is a disease with a poor outlook. Children with this disease develop nervous system problems, and can die young.
Review
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
