Glial Fibrillary Acidic Protein Alpha Subunit Antibody, Immunofluorescence Titer Assay, Serum
Use
This test is used for reporting an end titer result in serum specimens. It is useful for distinguishing autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy from infectious meningoencephalitis and idiopathic inflammatory central nervous system (CNS) disorders such as multiple sclerosis, vasculitis, and sarcoidosis, which are commonly considered in the differential diagnosis. The presence of GFAP-IgG indicates an immune-mediated, steroid-responsive disorder and suggests the clinician search for an associated malignancy.
Special Instructions
This test is only orderable as a reflex. Relevant clinical information and ordering provider details (name, phone number, address, email) must be provided.
Limitations
Negative results do not exclude the diagnosis of autoimmune meningoencephalomyelitis or cancer. Interference by coexisting non-neuron-specific autoantibodies can usually be eliminated by serologic absorption.
New York Approved
Methodology
Immunoassay (Indirect Immunofluorescence Assay)
Biomarkers
LOINC Codes
- 93423-2
- 93423-2
Result Turnaround Time
10 days
Related Documents
For more information, please review the documents below
Specimen
Serum
Volume
Not provided
Minimum Volume
1 mL
Causes for Rejection
Gross hemolysis, gross lipemia, gross icterus
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | 72 hours |
| Refrigerated | 28 days |
| Frozen | 28 days |