Hurler syndrome

Hurler syndrome
Patient with Hurler syndrome
CausesDeficiency of the alpha-L iduronidase enzyme
Differential diagnosisHurler-Scheie syndrome; Scheie syndrome; Hunter syndrome; other mucopolysaccharidoses
PrognosisDeath usually occurs before 12 years
Frequency1 in 100,000

Hurler syndrome, also known as mucopolysaccharidosis Type IH (MPS-IH), Hurler's disease, and formerly gargoylism, is a genetic disorder that results in the buildup of large sugar molecules called glycosaminoglycans (GAGs) in lysosomes. The inability to break down these molecules results in a wide variety of symptoms caused by damage to several different organ systems, including but not limited to the nervous system, skeletal system, eyes, and heart.

The underlying mechanism is a deficiency of alpha-L iduronidase, an enzyme responsible for breaking down GAGs.[1]: 544  Without this enzyme, a buildup of dermatan sulfate and heparan sulfate occurs in the body. Symptoms appear during childhood, and early death usually occurs. Other, less severe forms of MPS Type I include Hurler–Scheie syndrome (MPS-IHS) and Scheie syndrome (MPS-IS).

Hurler syndrome is classified as a lysosomal storage disease. It is clinically related to Hunter syndrome (MPS II);[2] however, Hunter syndrome is X-linked, while Hurler syndrome is autosomal recessive.

  1. ^ James WD, Berger TG, et al. (2006). Andrews' Diseases of the Skin: clinical Dermatology. Saunders Elsevier. ISBN 978-0-7216-2921-6.
  2. ^ "Mucopolysaccharidoses Fact Sheet". National Institute of Neurological Disorders and Stroke. 15 Nov 2017. Retrieved 11 May 2018.