Test Code GFATS Glial Fibrillary Acidic Protein Alpha Subunit Antibody, Immunofluorescence Titer Assay, Serum
Necessary Information
Provide the following information:
-Relevant clinical information
-Ordering provider name, phone number, mailing address, and e-mail address
Specimen Required
Only orderable as a reflex. For more information see:
ENS2 / Encephalopathy, Autoimmune Evaluation Serum
DMS2 / Dementia, Autoimmune Evaluation, Serum
EPS2 / Epilepsy, Autoimmune Evaluation, Serum
MAS1 / Autoimmune Myelopathy Evaluation, Serum
Testing Algorithm
If immunofluorescence assay (IFA) pattern suggests GFAP, then GFAP IFA titer and GFAP cell-binding assay (CBA) are performed at an additional charge.
Method Name
Only orderable as a reflex. For more information see:
ENS2 / Encephalopathy, Autoimmune Evaluation Serum
DMS2 / Dementia, Autoimmune Evaluation, Serum
EPS2 / Epilepsy, Autoimmune Evaluation, Serum
MAS1 / Autoimmune Myelopathy Evaluation, Serum
Indirect Immunofluorescence Assay (IFA)
Specimen Type
SerumSpecimen Minimum Volume
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
Antibody targeting glial fibrillary acidic protein (GFAP)-IgG is a biomarker of a subacute and progressive autoimmune meningitis, encephalitis, and myelitis that can mimic multiple sclerosis (MS) or other idiopathic inflammatory central nervous system (CNS) disorders such as sarcoidosis. Neurological manifestations include headache, optic neuropathy, transverse myelitis, cognitive decline, and cerebellar ataxia. Cerebrospinal fluid (CSF) is inflammatory. Cranial magnetic resonance (MR) imaging reveals linear perivascular enhancement oriented radially to ventricles. A paraneoplastic neurological context is common. Reported neoplasms accompanying neurological symptoms include adenocarcinomas (prostate and gastroesophageal), myeloma, melanoma, colonic carcinoid, parotid pleomorphic adenoma, and teratoma. If GFAP-IgG is detected by immunofluorescence assay (IFA), it is reflexed to a test for the alpha isoform of GFAP (GFAPalpha-IgG) by cell based assay.
Reference Values
Only orderable as a reflex. For more information see:
ENS2 / Encephalopathy, Autoimmune Evaluation Serum
DMS2 / Dementia, Autoimmune Evaluation, Serum
EPS2 / Epilepsy, Autoimmune Evaluation, Serum
MAS1 / Autoimmune Myelopathy Evaluation, Serum
<1:240
Day(s) Performed
Monday through Sunday
Report Available
10 daysPerforming Laboratory

CPT Code Information
86256