Voltage-Gated Potassium Channel (VGKC) Antibody, Serum
Also known as: VGKC AB
Use
Voltage-Gated Potassium Channel (VGKC) antibodies are associated with neuromuscular disorders such as neuromyotonia (Issacs syndrome) and Morvan syndrome. They are also connected to paraneoplastic neurological syndromes and limbic encephalitis; however, in limbic encephalitis, the causative antibodies may often be against LGI1 or CASPR2 proteins rather than potassium channel antigens. Many VGKC antibody-positive cases are negative for LGI1 and CASPR2 antibodies, implying that not all antigens in the VGKC complex are known. Determination of the clinical significance requires consideration of the patient's clinical history and additional laboratory tests.
Special Instructions
The assay is a screening test for VGKC antibody receptor complex-associated autoantibodies. It does not identify antibodies against LGI1 or CASPR2. Used to monitor antibody-positive individuals in the context of immunotherapy and/or plasmapheresis.
Limitations
This test cannot distinguish between antibodies to different potassium channel antigens and does not identify CASPR2 or LGI1 antibodies. The test is unable to demonstrate all VGKC complex-associated antibodies as all antigenic components are not yet known. Interpretation should be made in conjunction with clinical information and additional laboratory data.
New York Approved
Methodology
Immunoassay (RIA)
Biomarkers
LOINC Codes
- 41871-5
Result Turnaround Time
1-8 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
4 mL
Minimum Volume
0.5 mL
Container
ARUP Standard Transport Tube
Collection Instructions
Separate serum from cells within 1 hour.
Storage Instructions
Refrigerated.
Causes for Rejection
Plasma, grossly lipemic or icteric specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 2 weeks |
| Frozen | 1 month |
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