Voltage-Gated Potassium Channel (VGKC) Antibody

Test Code

93883

CPT Codes
83519

Preferred Specimen

1 mL serum

Minimum Volume

0.5 mL

Transport Container

Plastic screw-cap vial

Transport Temperature

Frozen

Specimen Stability

Room temperature: 48 hours
Refrigerated: 48 hours
Frozen: 73 days

Methodology
Radioimmunoassay (RIA)

FDA Status
This test was developed and its analytical performance characteristics have been determined by Quest Diagnostics. It has not been cleared or approved by FDA. This assay has been validated pursuant to the CLIA regulations and is used for clinical purposes.

Setup Schedule

Set up: Tues, Thurs; Report available: 8-15 days

Reference Range

<80 pmol/L

Clinical Significance

Limbic encephalitis (LE) is a paraneoplastic neurological syndrome often associated with small cell lung carcinoma and more rarely with testicular, breast, and other tumors. Clinical hallmarks of paraneoplastic limbic encephalitis are changing mental status, short-term memory impairment, seizures, confusion, and behavioral changes. Hu antibody-negative LE patients usually do not develop symptoms beyond the limbic system and appear to improve more often after treatment of the cancer than those who have Hu antibodies, suggesting that the pathogenesis of the LE in both groups could be different. Recent studies have detected antibodies to voltage-gated potassium channels (VGKC) in patients with LE, with and without associated tumors. Neurological symptoms were found to improve with a reduction of VGKC antibody levels.

Performing Laboratory

Quest Diagnostics Nichols Institute-San Juan Capistrano, CA

33608 Ortega Highway

San Juan Capistrano, CA 92675-2042

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.