Myelin Associated Glycoprotein (MAG) Antibodies, IgM and Sulfate-3-Glucuronyl Paragloboside (SGPG) Antibodies, IgM
Also known as: MAG/SGPG
Use
This test is used to assist in the diagnosis of autoimmune neuropathies. It measures the presence of IgM antibodies against myelin-associated glycoprotein (MAG) and sulfate-3-glucuronyl paragloboside (SGPG). Elevated concentrations of these antibodies suggest active demyelination and peripheral neuropathy. This test is not diagnostic on its own and should be used alongside other clinical parameters for accurate disease confirmation. SGPG IgM positive and MAG IgM negative results may indicate multi-focal motor neuropathy with conduction block.
Special Instructions
The test results are interpreted alongside clinical findings due to its lack of standalone diagnostic capability. It's imperative to separate serum from cells within two hours of collection for accurate testing. This testing process is conducted at ARUP Laboratories, which is a CLIA certified lab.
Limitations
An elevated IgM antibody level does not conclusively diagnose MAG or SGPG antibody-associated neuropathy on its own. False negatives can occur, hence the importance of comprehensive diagnostic assessment utilizing other clinical parameters. Additionally, urine and improperly handled or contaminated specimens are not accepted for testing.
New York Approved
Methodology
Immunoassay (ELISA)
Biomarkers
LOINC Codes
- 17314-6
- 31666-1
Result Turnaround Time
1-8 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
0.5 mL
Minimum Volume
0.1 mL
Container
ARUP Standard Transport Tube
Collection Instructions
Separate serum from cells ASAP or within 2 hours of collection.
Causes for Rejection
Urine. Contaminated, heat-inactivated, hemolyzed, icteric, or severely lipemic specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 48 hours |
| Refrigerated | 2 weeks |
| Frozen | 1 year |