Scheie syndrome

From WikiMD's Wellness Encyclopedia


Scheie syndrome is a disease caused by a deficiency in the enzyme iduronidase, leading to the buildup of glycosaminoglycans (GAGs) in the body. It is the most mild subtype of mucopolysaccharidosis type I; the most severe subtype of this disease is called Hurler Syndrome.

Scheie syndrome is characterized by corneal clouding, facial dysmorphism, and normal lifespan.[1][2] People with this condition may have aortic regurgitation.[3]

Symptoms[edit | edit source]

The symptoms of Scheie syndrome are variable, but are milder than Hurler Syndrome. Symptoms may begin to appear by age 5, but affected children are often not diagnosed until after age 10. Patients with Scheie Syndrome may have normal intelligence, or they may have mild learning impairments or psychiatric problems. Glaucoma, retinal degeneration, and clouded corneas may cause visual impairments. Aortic valve disease may be present, along with carpal tunnel syndrome, deformed hands and feet, stiff joints, or sleep apnea. People with Scheie syndrome may live into adulthood.[4]

Genetics[edit | edit source]

Scheie syndrome has an autosomal recessive pattern of inheritance.

Children with Scheie Syndrome carry two defective copies of the IDUA gene, which has been mapped to the 4p16.3 site on chromosome 4. This is the gene which encodes for the protein iduronidase. All patients with subtypes of MPS I have mutations in the same gene, leading to deficiencies of the same enzyme. However, patients with Scheie Syndrome have a greater level of iduronidase activity than patients with Hurler Syndrome.

Because Scheie syndrome is an autosomal recessive disorder, affected persons have two nonworking copies of the gene. A person born with one normal copy and one defective copy is called a carriers. They will produce less α-L-iduronidase than an individual with two normal copies of the gene. The reduced production of the enzyme in carriers, however, remains sufficient for normal function; the person should not show any symptoms of the disease.

History[edit | edit source]

In 1919, Gertrud Hurler, a German pediatrician, described a syndrome involving corneal clouding, skeletal abnormalities, and mental retardation. This became known as Hurler Syndrome.[5][6] In 1962, a milder variant of Hurler Syndrome was identified by Scheie, leading to the designation of Scheie syndrome.[7]

Diagnostic methods[edit | edit source]

Antenatal diagnosis Antenatal diagnosis is possible by measurement of enzymatic activity in cultivated chorionic villus or amniocyte and by genetic testing if the disease-causing mutation is known.

Treatment[edit | edit source]

  • Management should be carried out by a multidisciplinary team and should include physiotherapy to maintain range of movement.
  • The enzyme substitute (laronidase) obtained EU marketing authorization as an orphan drug in 2003.
  • Given through weekly infusions it leads to improvement of lung function and joint mobility.
  • [[Enzyme replacement therapy ] (ERT) should be started at diagnosis and may be beneficial in patients awaiting hematopoietic stem cell transplantation (HSCT).
  • Early treatment slows the progression of the disease.

Prognosis[edit | edit source]

Life expectancy for patients with Scheie syndrome may only be slightly affected.

See also[edit | edit source]

References[edit | edit source]

  1. Ropper AH, Samuels MA, "Chapter 37. Inherited Metabolic Diseases of the Nervous System" (Chapter). Ropper AH, Samuels MA: Adams and Victor's Principles of Neurology, 9e: http://www.accessmedicine.com/content.aspx?aID=3636356.
  2. "Scheie syndrome - National Library of Medicine - PubMed Health". ncbi.nlm.nih.gov. Retrieved 19 January 2014.
  3. Cite error: Invalid <ref> tag; no text was provided for refs named NINDS
  4. Hurler's syndrome at Who Named It?

External links[edit | edit source]

Classification
External resources


Contributors: Deepika vegiraju