Voltage-Gated Potassium Channel (VGKC) Antibody, CSF
Also known as: VGKC CSF
Use
Voltage-Gated Potassium Channel (VGKC) antibodies are associated with neuromuscular weakness as found in neuromyotonia (Issacs syndrome) and Morvan syndrome. VGKC antibodies are also linked to paraneoplastic neurological syndromes and limbic encephalitis, but VGKC antibody-associated limbic encephalitis may be due to antibodies targeting leucine-rich, glioma-inactivated 1 protein (LGI1) or contactin-associated protein-2 (CASPR2) rather than potassium channel antigens. Many VGKC-antibody positive cases test negative for LGI1 and CASPR2 IgG autoantibodies. Testing should be interpreted alongside the patient's clinical history and results from other laboratory tests.
Special Instructions
This test is New York state approved. It is not FDA cleared or approved. The test was developed and its performance characteristics were determined by ARUP Laboratories and is intended for clinical purposes in a CLIA certified laboratory.
Limitations
The assay does not identify contactin-associated protein 2 (CASPR2) antibody or leucine-rich glioma inactivated 1 protein (LGI1) antibodies. The detection of VGKC antibodies alone does not specify whether the antibodies are directed against known components such as LGI1 or CASPR2. Some VGKC complex antigens remain unidentified, and the clinical relevance of these may vary.
New York Approved
Methodology
Immunoassay (RIA)
Biomarkers
LOINC Codes
- 68913-3
Result Turnaround Time
1-8 days
Related Documents
For more information, please review the documents below
Specimen
Cerebrospinal Fluid
Volume
4 mL
Minimum Volume
0.5 mL
Container
ARUP Standard Transport Tube
Storage Instructions
Refrigerated
Causes for Rejection
Plasma. Grossly lipemic or icteric specimens.
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 48 hours |
| Refrigerated | 2 weeks |
| Frozen | 1 month |
Other tests from different labs that may be relevant