Leucine-Rich, Glioma-Inactivated Protein 1 Antibody, IgG with Reflex to Titer
2009456
Ordering Recommendation
Aids in diagnosis of Leucine-rich Glioma Inactivated 1 Protein (LGI1) antibody disorders associated with limbic encephalitis, hyponatremia, myoclonic movements. Disorders are rarely associated with tumors. Use to manage antibody-positive (LGI1) individual following immunotherapy and/or plasmapheresis.
Mnemonic
LGI1 IGG
Methodology
Semi-Quantitative Indirect Fluorescent Antibody
Performed
Wed
Reported
1-8 days  
New York DOH Approval Status
This test is New York DOH approved.
Submit With Order
Specimen Required
Patient Preparation
  
Collect
Serum separator tube.  
Specimen Preparation
Separate serum from cells within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.2 mL)  
Storage/Transport Temperature
Refrigerated.  
Unacceptable Conditions
CSF or plasma. Contaminated, hemolyzed, or severely lipemic specimens.  
Remarks
  
Stability
After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)  
Reference Interval
Less than 1:10  
Interpretive Data
Leucine-rich, glioma-inactivated 1 protein (LGI1) IgG antibody may occur as part of the voltage-gated potassium channel (VGKC) complex antibodies.

The presence of LGI1 IgG antibody is mainly associated with limbic encephalitis, hyponatremia and myoclonic movements. LGI1 IgG antibody is rarely associated with tumors but may occur infrequently in Morvan syndrome, neuromyotonia and idiopathic epilepsy. The full-spectrum of clinical disorders associated with the LGI1 IgG antibody continues to be defined. Results should be interpreted in correlation with the patient's clinical history and other laboratory findings.

This indirect fluorescent antibody assay utilizes leucine-rich, glioma-inactivated 1 protein (LGI1) transfected cell lines for the detection and semi-quantification of the LGI1 IgG antibody.

See Compliance Statement D: www.aruplab.com/CS
Statement D: This test was developed and its performance characteristics determined by ARUP Laboratories. The U.S. Food and Drug Administration has not approved or cleared this test; however, FDA clearance or approval is not currently required for clinical use. The results are not intended to be used as the sole means for clinical diagnosis or patient management decisions.
 
Note
If LGI1 antibody IgG is positive, then LGI1 antibody IgG titer will be added. Additional charges apply.
CPT Code(s)
86255; if reflexed add 86256
Components
Component Test Code*Component Chart NameLOINC
2009457LGI1 Ab IgG Screen by IFA 
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases