Voltage-Gated Potassium Channel (VGKC) Complex Antibody Panel with Reflex to Titer, CSF
Ordering Recommendation
Detect antibodies to voltage-gated potassium channel (VGKC) antibody receptor complex-associated, leucine-rich glioma inactivated 1 protein (LGI1) and contactin associated protein 2 (CASPR2). Antibodies are associated with acquired neuromyotonia, limbic encephalitis, painful neuropathy, Morvan syndrome, and rare tumors (eg, thymoma, small cell lung cancer). Serum is the preferred specimen type; see Voltage-Gated Potassium Channel (VGKC) Antibody with Reflex to LGI1 and CASPR2 Screen and Titer, Serum (2009463).
Methodology
Quantitative Radioimmunoassay/Semi-Quantitative Cell-Based Indirect Fluorescent Antibody
Performed
Wed
Reported
1-8 days
New York DOH Approval Status
Specimen Required
CSF.
Transfer 4 mL CSF to an ARUP Standard Transport Tube. (Min: 1.0 mL)
Refrigerated.
Plasma. Grossly lipemic or icteric specimens.
After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 month
Reference Interval
Test Number |
Components |
Reference Interval |
---|---|---|
Voltage-Gated Potassium Channel Ab, CSF | 0.0-1.1 pmol/L | |
LGI1 Ab IgG CBA-IFA Screen, CSF | Less than 1:1 | |
CASPR2 Ab IgG CBA-IFA Screen, CSF | Less than 1:1 |
Interpretive Data
This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.
Component | Interpretive Data |
---|---|
Voltage-Gated Potassium Channel Ab, CSF | 0.0-1.1 pmol/L: Negative 1.2 pmol/L or greater: Positive |
Laboratory Developed Test (LDT)
Note
If LGI1 antibody IgG is positive, then LGI1 antibody IgG titer will be added. If CASPR2 antibody IgG is positive, then CASPR2 antibody IgG titer will be added. Additional charges apply.
Hotline History
Hotline History
CPT Codes
83519; 86255 x2; if reflexed add 86256 per titer
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
3001388 | Voltage-Gated Potassium Channel Ab, CSF | 68913-3 |
3001987 | CASPR2 Ab IgG CBA-IFA Screen, CSF | 90820-2 |
3001991 | LGI1 Ab IgG CBA-IFA Screen, CSF | 90830-1 |