Gamma Aminobutyric Acid Receptor, Type B (GABA-BR) Antibody, IgG by CBA-IFA With Reflex to Titer, CSF
Ordering Recommendation
Aid in diagnosis of limbic encephalitis. May be used in monitoring treatment response in individuals who are antibody positive. The presence of GABA-BR antibodies may be associated with seizures; GABA-BR encephalitis may be paraneoplastic as about 50% of cases are associated with small cell lung cancer.
New York DOH Approval Status
Specimen Required
CSF.
Transfer 0.5 mL CSF to an ARUP standard transport tube. (Min: 0.15 mL)
Refrigerated.
Hemolyzed, contaminated, or severely lipemic specimens.
Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 month
Methodology
Semi-Quantitative Cell-Based Indirect Fluorescent Antibody
Performed
Wed
Reported
1-8 days
Reference Interval
Less than 1:1
Interpretive Data
Gamma-amino butyric acid receptor, type B (GABA-BR) antibody is found in a subset of patients with autoimmune epilepsy and other autoimmune neurologic phenotypes; it may occur with or without associated tumor. Decreasing antibody levels may be associated with therapeutic response. A negative test result does not rule out a diagnosis of autoimmune neurologic disease. Results should be interpreted in correlation with the patients clinical history and other laboratory findings.
This indirect fluorescent antibody assay utilizes GABA-BR transfected cell lines for the detection and semiquantification of GABA-BR IgG antibody.
Laboratory Developed Test (LDT)
Note
If Gamma Aminobutyric Acid Receptor, Type B (GABA-BR) Antibody, IgG by IFA with Reflex to Titer, CSF is positive, then a Gamma Aminobutyric Acid Receptor, Type B (GABA-BR) Antibody Titer, IgG, CSF is performed. Additional charges apply.
Hotline History
Hotline History
CPT Codes
86255; if reflexed, add 86256
Components
Component Test Code* | Component Chart Name | LOINC |
---|---|---|
3001268 | GABA-BR Ab IgG CBA-IFA Screen, CSF | 82984-6 |
Aliases
- GABA
- GABA Receptor
- GABA Reflex
- GABA Titer
- GABA-B