Test Details
Methodology
Immunofluorescence, Immunoblot
Result Turnaround Time
4 days
Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Use
Leucine-rich glioma-inactivated 1 (LGI1) antibody encephalitis is a rare autoimmune voltage-gated potassium channel complex (VGKC) antibody-associated limbic encephalitis. Specifically, it is classified as an ant neuronal surface antigen- or ant-synaptic protein-associated autoimmune encephalitis. In addition to the common symptoms of limbic encephalitis such as cognitive impairment, seizures and psychiatric disorders, this disease is also associated with faciobrachial dystonic seizure (FBDS) and refractory hyponatremia. Unlike other limbic encephalitides, LGI1 antibody encephalitis is rarely accompanied by tumors and shows a good response to immunotherapy.
This test works as an aid in the diagnosis of LGI1 antibody disorders. This test is also useful in managing antibody-positive (LGI1) individual following immunotherapy and/or plasmapheresis.
This indirect fluorescent antibody assay utilizes LGI1 transfected cell lines for the detection and semi-quantification of the LGI1 IgG antibody.
Special Instructions
If reflex test is performed, additional charges/CPT code(s) may apply.
Limitations
This test was developed and its performance characteristics determined by Labcorp in accordance with CLIA requirements. This test has not been cleared or approved by the Food and Drug Administration.
Specimen Requirements
Specimen
Cerebrospinal fluid (CSF)
Volume
2 mL
Minimum Volume
1 mL
Container
Sterile plastic tube
Stability Requirements
Temperature | Period |
|---|---|
Room temperature | 14 days |
Refrigerated | 14 days |
Frozen | 14 days |
Freeze/thaw cycles | Stable x3 |
Storage Instructions
Room temperature
Causes for Rejection
Gross hemolysis; grossly lipemic; gross icterus
References
LOINC® Map
| Order Code | Order Code Name | Order Loinc | Result Code | Result Code Name | UofM | Result LOINC |
|---|---|---|---|---|---|---|
| 505695 | Anti-LGI1, CSF | 90830-1 | 505637 | LGI1 Antibody, Cell-based IFA | 90830-1 | |
| Order Code | 505695 | |||||
| Order Code Name | Anti-LGI1, CSF | |||||
| Order Loinc | 90830-1 | |||||
| Result Code | 505637 | |||||
| Result Code Name | LGI1 Antibody, Cell-based IFA | |||||
| UofM | ||||||
| Result LOINC | 90830-1 |
| Order Code | Order Name | Result Code | Result Name | UofM | Result LOINC | |
|---|---|---|---|---|---|---|
| Reflex 1 | 505609 | Anti-LGI1 Antibody Titer | 505609 | Anti-LGI1 Antibody Titer | 90831-9 | |
| Reflex 1 | ||||||
| Order Code | 505609 | |||||
| Order Name | Anti-LGI1 Antibody Titer | |||||
| Result Code | 505609 | |||||
| Result Name | Anti-LGI1 Antibody Titer | |||||
| UofM | ||||||
| Result LOINC | 90831-9 | |||||