National Organization for Rare Disorders, Inc.
It is possible that the main title of the report Sialidosis is not the name you expected. Please check the synonyms listing to find the alternate name(s) and disorder subdivision(s) covered by this report.
- ML I
- alpha-neuraminidase deficiency
- cherry red spot and myoclonus syndrome
- glycoprotein neuraminidase, deficiency of
- lipomucopolysaccharidosis type I
- mucolopidosis type I
- neuraminidase deficiency
- sialidase deficiency
Sialidosis, also known as mucolipidosis type I, is a rare inherited metabolic disorder characterized by a deficiency of the enzyme neuraminidase (sometimes referred to as sialidase). Deficiency of neuraminidase results in the abnormal accumulation of toxic materials in the body. Sialidosis is divided into two types (i.e., type I and type II). Sialidosis type I usually becomes apparent during the second decade of life with the development of sudden involuntary muscle contractions (myoclonus), distinctive red spots (cherry-red macules) in the eyes, and sometimes additional neurological findings. Sialidosis type II is usually more severe than sialidosis type I. Type II often begins during infancy or later during childhood and is characterized by cherry-red macules, mildly coarse facial features, skeletal malformations and mild cognitive impairment. Sialidosis is inherited as an autosomal recessive trait.
Sialidosis belongs to a group of diseases known as the lysosomal storage disorders (LSDs). Lysosomes are particles bound in membranes within cells that function as the primary digestive units within cells. Enzymes within lysosomes break down or digest particular nutrients, such as complex molecules composed of a sugar attached to a protein (glycoproteins). In sialidosis patients, low levels or inactivity of the neuraminidase enzyme leads to the abnormal accumulation these compounds in the cells with unwanted consequences. Sialidosis is also classified as one of the mucolipidoses, a subgroup of the LSDs.
CLIMB (Children Living with Inherited Metabolic Diseases)
176 Nantwich Road
Crewe, CW2 6BG
Vaincre Les Maladies Lysosomales
2 Ter Avenue
1825 K Street NW, Suite 1200
Washington, DC 20006
NIH/National Institute of Diabetes, Digestive & Kidney Diseases
Office of Communications & Public Liaison
Bldg 31, Rm 9A06
31 Center Drive, MSC 2560
Bethesda, MD 20892-2560
Society for Mucopolysaccharide Diseases
White Lion Road
Buckinghamshire, HP7 9LP
Canadian Society for Mucopolysaccharide and Related Diseases, Inc.
PO Box 30034
British Columbia, V7H 2Y8
International Advocate For Glycoprotein Storage Diseases
20880 Canyon View Drive
Saratoga, CA 95070
Genetic and Rare Diseases (GARD) Information Center
PO Box 8126
Gaithersburg, MD 20898-8126
Hide & Seek Foundation for Lysosomal Disease Research
6475 East Pacific Coast Highway Suite 466
Long Beach, CA 90803
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It is possible that the title of this topic is not the name you selected. Please check the Synonyms listing to find the alternate name(s) and Disorder Subdivision(s) covered by this report
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Last Updated: 5/28/2010
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