Leucine-Rich, Glioma-Inactivated Protein 1 Antibody, IgG CBA-IFA and Contactin-Associated Protein-2 Antibody, IgG CBA-IFA with Reflex to Titers, Serum
Ordering Recommendation
Aid in diagnosis of leucine-rich glioma inactivated 1 protein (LGI1) antibody disorders associated with limbic encephalitis, hyponatremia, and myoclonic movements. Disorders are rarely associated with tumors.
Aid in diagnosis of contactin associated protein 2 (CASPR2) antibody disorders associated with acquired neuromyotonia, limbic encephalitis, painful neuropathy, and Morvan syndrome.
Use to manage antibody-positive (LGI1 or CASPR2) individual following immunotherapy and/or plasmapheresis.
New York DOH Approval Status
Specimen Required
Serum separator tube.
Separate serum from cells within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.2 mL)
Refrigerated.
CSF or plasma. Contaminated, hemolyzed, or severely lipemic specimens.
After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)
Methodology
Semi-Quantitative Cell-Based Indirect Fluorescent Antibody
Performed
Wed
Reported
1-8 days
Reference Interval
Test Number |
Components |
Reference Interval |
---|---|---|
CASPR2 Ab IgG CBA-IFA Screen, Serum | Less than 1:10 | |
LGI1 Ab IgG CBA-IFA Screen, Serum | Less than 1:10 |
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.
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
86255 x2; if reflexed add 86256 per titer
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
2009453 | CASPR2 Ab IgG CBA-IFA Screen, Serum | 82979-6 |
2009457 | LGI1 Ab IgG CBA-IFA Screen, Serum | 82978-8 |