Test Code GFATS Glial Fibrillary Acidic Protein Alpha Subunit Antibody, Immunofluorescence Titer Assay, Serum (Non-Orderable)
Necessary Information
Provide the following information:
-Relevant clinical information
-Ordering healthcare professional name, phone number, mailing address, and email address
Specimen Required
Only orderable as a reflex. For more information see PNEFS / Neuroimmunology Antibody Follow-up, Serum.
Supplies: Sarstedt Aliquot Tube, 5 mL (T914)
Collection Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Submission Container/Tube: Plastic vial
Specimen Volume: 4 mL Serum
Collection Instructions: Within 2 hours of collection, centrifuge and aliquot serum into a plastic vial.
Useful For
Only orderable as a reflex. For more information see PNEFS / Neuroimmunology Antibody Follow-up, Serum.
Reporting an end titer result in serum specimens
Distinguishing autoimmune glial fibrillary acidic protein (GFAP) astrocytopathy from infectious meningoencephalitis and idiopathic inflammatory central nervous system disorders, such as multiple sclerosis, vasculitis and sarcoidosis, disorders commonly considered in the differential diagnosis
Alerting the clinician that the patient has an immune-mediated, steroid-responsive disorder and to search for a malignancy
Method Name
Only orderable as a reflex. For more information see PNEFS / Neuroimmunology Antibody Follow-up, Serum.
Indirect Immunofluorescence Assay (IFA)
Reporting Name
GFAP IFA Titer, SSpecimen Type
SerumSpecimen Minimum Volume
Serum: 1 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Serum | Refrigerated (preferred) | 28 days |
| Frozen | 28 days | |
| Ambient | 72 hours |
Reject Due To
| Gross hemolysis | Reject |
| Gross lipemia | Reject |
| Gross icterus | Reject |
Clinical Information
Glial fibrillary acidic protein (GFAP)-IgG is a biomarker of a subacute, progressive autoimmune meningitis, encephalitis, and myelitis. These disorders may mimic multiple sclerosis or other idiopathic inflammatory central nervous system disorders, such as sarcoidosis. Neurologic manifestations include headache, optic neuropathy, transverse myelitis, cognitive decline, and cerebellar ataxia. Cerebrospinal fluid findings are inflammatory. Cranial magnetic resonance imaging reveals linear perivascular enhancement oriented radially to the ventricles. A paraneoplastic neurologic association is common. Reported neoplasms accompanying neurologic symptoms include adenocarcinomas of the prostate and gastroesophageal tract, myeloma, melanoma, colonic carcinoid, parotid pleomorphic adenoma, and teratoma. If GFAP-IgG is detected by immunofluorescence assay, testing for the alpha isoform of GFAP (GFAPalpha-IgG) by cell-based assay is performed.
Reference Values
Only orderable as a reflex. For more information see PNEFS / Neuroimmunology Antibody Follow-up, Serum.
<1:240
Day(s) Performed
Monday through Sunday
Report Available
10 daysPerforming Laboratory
Mayo Clinic Laboratories in Rochester
Test 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
86256