Category: |
Neuroimmunology |
---|---|
Test Code: | 508 |
Disease: | Paraneoplastic Syndromes |
Methodology: | ELISA, Indirect Immunofluorescence, Western Blot confirmation if appropriate |
Reference Range: | See reference range for individual tests. |
Note: | Requested Sample Volume: 5 mL Minimum Sample Volume: 2 mL |
CPT Code: | CPT Codes: 83520 (x10); 83516; 86255(x5) & 84181 |
Schedule / Turnaround Time: | See individual tests for scheduling and turnaround time. |
Specimen Requirements: |
Specimen need not be refrigerated or frozen. Collect 2-3 ml of blood in a red top or serum separator tube. If possible, separate serum from clot and place into white tube provided with Immco Diagnostics’ collection kits. If separation facilities are not available, the blood can be sent in the tube used for collection. |
Sample Stability: |
Sample is stable at ambient temperature during shipment. If sample is stored prior to shipment, it is stable refrigerated (2-8˚C) up to five days and frozen (-20˚C or lower) up to one year. |
Relevance: |
Cause for rejection: Specimens other than serum. Grossly hemolyzed, lipemic or icteric samples. Clinical Relevance: GM1, GD1b, GQ1b, Asialo GM1, GD1a Antibodies against glycolipids (GM1, GD1a, GD1b, GQ1b, Asialo GM1 and sulfatides) are present in Guillain- Barre syndrome(GBS), IgM paraproteinemic neuropathy, and chronic demyelinating polyneuropathy. Antibodies to one or more glycolipids are present in 60-70% of patients with GBS. The titers of antiglycolipid antibodies are higher in acute phase and decrease with clinical improvement. Antibodies to GM1 and/or GD1b are frequently found in acute phase GBS. The two antibodies together occur in 20% of these cases, anti-GM1 without GD1b antibodies in about 10% and anti-GD1b without GM1 antibodies in about 10% of GBS patients.Antibodies to GQ1b of IgG isotype are present in 95% of patients with Miller Fisher syndrome (MFS). The titers of these antibodies fluctuate with disease activity. IgM paraproteinemia is often associated with peripheral neuropathies. These antibodies are present in one half of patients with specificity for SGPG, GD1b and other gangliosides. Anti-GM1 IgM are usually associated with motor dominant or sensorimotor neuropathies. These antibodies are also elevated in multifocal neuropathies such as GBS, CIDP and other immunological diseases. |