Test Code GBACC Gamma-Amino Butyric Acid Type A (GABA-A) Receptor Antibody by Cell Binding Assay, Spinal Fluid
Specimen Required
Container/Tube: Sterile vial
Specimen Volume: 1 mL
Secondary ID
620231Useful For
Evaluating patients with suspected autoimmune encephalitis and autoimmune epilepsy
Method Name
Cell Binding Assay (CBA)
Reporting Name
GABA-A-R Ab CBA, CSFSpecimen Type
CSFSpecimen Minimum Volume
0.4 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
CSF | Refrigerated (preferred) | 28 days | |
Frozen | 28 days | ||
Ambient | 72 hours |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | Reject |
Clinical Information
Gamma-amino butyric acid type A (GABA-A) receptor autoantibodies are highly predictive of GABA-A receptor autoimmune encephalitis. Seropositive GABA-A receptor encephalitis patients have characteristic clinical-radiologic presentations including frequent seizures and multifocal lesions in the white matter. The majority of patients are treatable with immunotherapy.
Reference Values
Negative
Interpretation
Seropositivity for gamma-amino butyric acid type A receptor autoantibodies supports the clinical diagnosis of autoimmune encephalitis with neurological presentations including seizures and multifocal lesions in the white matter. A search for thymoma cancer, and a trial of immunotherapy should be considered.
Method Description
Patient specimen is applied to a composite slide containing transfected and nontransfected HEK-293 cells. After incubation and washing, fluorescein-conjugated goat-antihuman IgG is applied to detect the presence of patient IgG binding.(Package insert: IIFT: Neurology Mosaics, Instructions for the indirect immunofluorescence test. EUROIMMUN, FA_112d-1_A_UK_C13, 02/2019)
Day(s) Performed
Monday through Sunday
Performing Laboratory
Mayo Clinic Laboratories in RochesterTest Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
86255
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
GBACC | GABA-A-R Ab CBA, CSF | 103715-9 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
620231 | GABA-A-R Ab CBA, CSF | 103715-9 |
Forms
If not ordering electronically, complete, print, and send a Neurology Specialty Testing Client Test Request (T732) with the specimen.