Gamma-Aminobutyric Acid Receptor, Type A (GABA-AR) Antibody, IgG by CBA-IFA with Reflex to Titer, CSF
Aids in the diagnosis of limbic encephalitis and autoimmune epilepsy. May be used to monitor treatment response in individuals who are antibody positive. The presence of GABA-AR antibodies may be associated with refractory seizures, memory loss, behavior changes, abnormal movements, and decreased level of consciousness. GABA-AR encephalitis may be paraneoplastic, but tumor type is variable (eg, thymoma, small cell lung cancer, rectal cancers, and hematologic malignancy). GABA-AR encephalitis may also be associated with post-viral and autoimmune diseases.
Semiquantitative Cell-Based Indirect Fluorescent Antibody
New York DOH Approval Status
Transfer 0.5 mL CSF to an ARUP standard transport tube. (Min: 0.15 mL)
Grossly hemolyzed or contaminated specimens.
Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 month (Three freeze/thaw cycles are acceptable)
Less than 1:1
Gamma-aminobutyric acid receptor, type A (GABA-AR) antibody is found in a subset of patients with autoimmune encephalitis or autoimmune epilepsy and may occur with or without an associated tumor. A negative test result does not rule out a diagnosis of autoimmune limbic encephalitis or autoimmune epilepsy. Interpretation of any antineural antibody test requires clinical correlation.
This indirect fluorescent antibody assay utilizes GABA-AR transfected cell lines for detection and semiquantification of GABA-AR IgG antibody.
Laboratory Developed Test (LDT)
If GABA-AR antibody IgG is positive, then GABA-AR antibody IgG titer will be added. Additional charges apply.
86255; if reflexed, add 86256
|Component Test Code*||Component Chart Name||LOINC|
|3006004||GABA-AR Ab IgG CBA-IFA Screen, CSF|
- autoimmune encephalitis
- autoimmune epilepsy
- Limbic encephalitis