INDIVIDUAL TEST 996
GFAp antibodies
IndicationInvestigation on suspicion of autoimmune CNS-diseases
MethodCell-based assay (CBA); indirect immunofluorescence on GFAp transfected cells. The method is not yet validated.
AnswerThe result is reported as negative or positive.
InterpretationAutoantibodies against GFAp in CSF have been reported in autoimmune CNS disease with meningo-encephalo-myelitis or parts thereof and are referred to as GFAp astrocyte disease. Symptoms of encephalopathy with epileptic seizures, meningism, headache, cognitive impairment (memory disturbance, confusion) and myelopathy are described as most common. Also, optic edema with blurred vision (often without pain) may occur and area posterior syndrome has been reported.
In a recent report from The Mayo Clinic, 88% of 102 patients with anti-GFAp had ovious cell proliferation in CSF with mononuclear cell dominance (range 13-550 x10E6 / L) and just over 50% had oligoclonal bands.
The presence of anti-GFAp may occur isolated but is detected together with anti-NMDAR-antibodies in about 20% and with anti-AQP4-antibodies in about 10% of cases. Usually, adults are affected, but 10% of reported cases are children. Anti-GFAp can appear para-malignant and is detected a couple of years before known cancer diagnosis. The analysis is performed in CSF which gives the highest specificity and sensitivity.
References
- Wei, P., Zhang, W., Yang, L. et al., Serum GFAP autoantibody as an ELISA-detectable glioma marker. Tumor Biol. 34, 2283–2292 (2013). PMID: 23589055
- Fang B. et al., Autoimmune Glial Fibrillary Acidic Protein Astrocytopathy: A Novel Meningoencephalomyelitis. JAMA Neurol. 2016 Nov 1;73(11):1297-1307. PMID: 27618707
- Shan F. et al., Autoimmune Glial Fibrillary Acidic Protein Astrocytopathy: A Review of the Literature. Front Immunol. 2018 Dec 5;9:2802. PMID: 30568655
- Kunchok A. et al., Autoimmune glial fibrillary acidic protein astrocytopathy. Curr Opin Neurol. 2019 Jun;32(3):452-458. PMID: 30724768
ENSKILD ANALYS 996
GFAp-antikroppar
IndikationUtredning vid misstanke om autoimmun CNS-sjukdom
MetodCell-based assay (CBA); indirekt immunofluorescens på GFAp-transfekterade celler. Metoden är ännu inte validerad.
SvarResultatet rapporteras som negativt eller positivt.
TolkningAutoantikroppar mot GFAp i likvor har rapporterats vid autoimmun CNS-sjukdom med meningo-encefalo-myelit eller delar därav och benämns GFAp-astrocyt-sjukdom. Symtom på encefalopati med epileptiska anfall, meningism, huvudvärk, kognitiv påverkan (minnesrubbning, konfusion) och myelopati beskrivs vara vanligast. Även optikus ödem med suddig syn (ofta utan smärta) kan förekomma och area postrema syndrom har rapporterats.
I en färsk rapport från The Mayo Clinic hade 88% av 102 patienter med anti-GFAp påtaglig cellstegring i likvor med dominans av mononukleära celler (range 13–550 x10E6/L) och drygt 50% hade oligoklonala band.
Förekomst av anti-GFAp kan förekomma isolerat men påvisas tillsammans med anti-NMDAR-ak i ca 20% och med anti-AQP4 i ca 10% av fallen. Vanligtvis drabbas vuxna, men 10% av rapporterade fall är barn. Anti-GFAp kan förekomma paramalignt och påvisas ett par år före känd cancerdiagnos. Analysen utförs i likvor vilket ger högst specificitet och sensitivitet.
Referenser
- Wei, P., Zhang, W., Yang, L. et al., Serum GFAP autoantibody as an ELISA-detectable glioma marker. Tumor Biol. 34, 2283–2292 (2013). PMID: 23589055
- Fang B. et al., Autoimmune Glial Fibrillary Acidic Protein Astrocytopathy: A Novel Meningoencephalomyelitis. JAMA Neurol. 2016 Nov 1;73(11):1297-1307. PMID: 27618707
- Shan F. et al., Autoimmune Glial Fibrillary Acidic Protein Astrocytopathy: A Review of the Literature. Front Immunol. 2018 Dec 5;9:2802. PMID: 30568655
- Kunchok A. et al., Autoimmune glial fibrillary acidic protein astrocytopathy. Curr Opin Neurol. 2019 Jun;32(3):452-458. PMID: 30724768