Lab Test

Voltage Gated Calcium Channel IgG (LEMS) Autoantibodies

LEMS Autoantibody Test, Lambert-Eaton Myasthenic Syndrome (LEMS)

Test Codes

ARUP: 0092628, EPIC: LAB6852, Beaker: XVGCC

Specimen Collection Criteria

Collect (preferred specimen): One plain Red-top tube.
Also acceptable: One Gold-top SST tube.

Physician Office/Draw Specimen Preparation

Let specimen clot 30-60 minutes then centrifuge to separate serum from cells. Transfer serum to a plastic transport tube and refrigerate (2-8°C or 36-46°F).

Preparation for Courier Transport

Transport: 1.0 mL serum, refrigerated (2-8°C or 36-46°F). (Minimum: 0.2 mL)

Rejection Criteria

  • Specimens not collected and processed as indicated.
  • Gross Hemolysis or lipemia
  • Plasma or CSF

In-Lab Processing

Let specimen clot 30-60 minutes then centrifuge to separate serum from cells. Transfer serum to a plastic transport tube and refrigerate (2-8°C or 36-46°F).

Transport: 1.0 mL serum, refrigerated (2-8°C or 36-46°F). (Minimum: 0.2 mL)

Storage

Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 72 hours
Refrigerated (2-8°C or 36-46°F): 14 days
Frozen (-20°C/-4°F or below): 30 days

Specimen Storage in Department Prior to Disposal:

Specimen retention time is determined by the policy of the reference laboratory. Contact the Send Outs Laboratory with any questions.

Laboratory

Sent to ARUP Laboratory in Salt Lake City, UT.

Performed

Tuesday
Results available in 2-9 days.

Reference Range

By report.

Test Methodology

Quantitative Radioimmunoassay

Interpretation

Voltage-gated calcium channel (VGCC) autoantibodies are characteristic of Lambert-Eaton Myasthenic Syndrome (LEMS) with or without small-cell lung cancer. VGCC autoantibodies are also found, albeit less frequently and generally in low amounts, in paraneoplastic disease associated with lung, ovarian or breast carcinomas; in carcinomas (without LEMS or other paraneoplastic syndrome) and occasionally in neurological diseases such as amyotrophic lateral sclerosis. This assay detects p-type VGCC autoantibodies using omega-conotoxin M toxin (omega-conotoxin MVIIC).

Clinical Utility

These autoantibodies are found in Lambert-Eaton syndrome, in some patients with cancer without Lambert-Eaton syndrome and in a few patients with other neurological diseases.

CPT Codes

83519
LOINC:  33980-4

Contacts

Last Updated

7/15/2021

Microtainer® and Vacutainer® are registered trademarks of Becton, Dickinson and Company.
UroVysion® is a registered trademark of Abbott Laboratories. ThinPrep® is a registered trademark of Hologic, Incorporated.