Voltage-Gated Potassium Channel Antibodies
Label Mnemonic: VGKCA
Epic Lab Code: LAB7733
Downtime Form: A-1a Miscellaneous Request
Commercial Mail-out Laboratory
5231 RCP
356-8593
Specimen(s):
Serum
Collection Medium:
and
Red top tube 5 mL (Clot Activator) Red top tube 5 mL (Clot Activator)
Minimum:
Preferred Minimum: 4 mL serum
Rejection Criteria:
Plasma. Grossly lipemic or icteric specimens.
Turn Around Time:
1-8 days upon receipt at reference laboratory.
Reference Range:
Negative: 31 pmol/L or less Indeterminate: 32-87 pmol/L Positive: 88 pmol/L or greater
Interpretive Data:
Voltage-Gated Potassium Channel (VGKC) antibodies are associated with neuromuscular weakness as found in neuromyotonia (also known as Issacs syndrome) and Morvan syndrome. VGKC antibodies are also associated with paraneoplastic neurological syndromes and limbic encephalitis; however, VGKC antibody-associated limbic encephalitis may be associated with antibodies to leucine-rich, glioma-inactivated 1 protein (Lgi1) or contactin-associated protein-2 (Caspr-2) instead of potassium channel antigens. The clinical significance of this test can only be determined in conjunction with the patientís clinical history and related laboratory testing.
Methodology:
Quantitative Radioimmunoassay
CPT Code:
83519