In glycoprotein storage diseases (GSDs), certain subtypes of congenital disorders of glycosylation (CDGs), and in the mucolipidoses, there is an accumulation of oligosaccharides, free glycans, glycoamino acids, glycolipid and glycopeptide in the urine. Glycoprotein storage diseases are genetic conditions caused by the body's inability to produce specific enzymes. Normally, the body uses enzymes to process, break down and recycle materials in cells. In individuals with GSD and related diseases, the missing or insufficient enzyme prevents the proper processing and recycling process. This results in the storage of materials, called oligosaccharides or free glycans and glycoamino acids in virtually every cell of the body. As a result, cells do not perform properly and may cause progressive damage throughout the body, including the heart, bones, joints, respiratory system, immune system and central nervous system.
While the disease may or may not be apparent at birth, signs and symptoms develop with age as more cells become damaged by the accumulation of materials. The symptoms of these diseases may vary based on syndrome type, and in some cases may resemble a mucopolysaccharidosis.
This urinary oligosaccharide and glycan screening uses MALDI-TOF/TOF technology, which provides a better sensitivity and specificity than traditional TLC methods. The MALDI-TOF/TOF method successfully detects subtle excretions of abnormal oligosaccharides in mucolipidosis II and III ( I cell disease) as well as other oligosaccharidosis.
Conditions screened for include the following:
- Alpha-mannosidosis
- Asparylglucosaminuria
- Beta-mannosidosis
- CDGIIb
- Fucosidosis