INDIVIDUAL TEST 730
Amphiphysin Antibodies (IgG)
Indication
Suspicion of paraneoplastic syndrome and autoimmune encephalitis.
Sample material
Serum
- Minim. volume: 0,5 mL
- Minim. volume: 2,0 mL
Transport
Within Sweden
- room temperature
International
- cold
Method
Immunoblot/ Indirect immunofluorescence(IIF)
According to Updated Diagnostic Criteria for Paraneoplastic Neurologic Syndromes, anti-neuronal antibodies should be detected by at least two independent methods to be reliable. At Wieslab IIF and immunoblot are used.
Reference interval
Serum
- Immunoblot: <5 negative
- Indirect Immunofluorescence: <1:10 negative
Likvor
- Immunoblot: negative
- Indirect immunofluorescence: negative
Result
Serum
- Immunoblot: results are reported as negative, borderline, or positive with an intensity value.
- Indirect immunofluorescence (IIF): results are reported as negative or positive. Positive results will be titrated.
CSF
- Immunoblot: results are reported as negative, borderline, or positive.
- Indirect immunofluorescence (IIF): results are reported as negative or positive.
Interpretation
Antibodies against Amphiphysin occur in patients with the paraneoplastic variant of Stiff person syndrome but can also be seen in limbic encephalitis and are associated with breast cancer and small cell lung cancer. Neurological symptoms can precede cancer diagnosis by up to 5 years.
Antibodies against Amphiphysin are graded as High-risk antibodies with a frequency of 80% of underlying cancer and a positive result yield 3 points PNS score, according to Updated Diagnostic Criteria for Paraneoplastic Neurologic Syndromes.
References
- Lancaster E et al. Neurology. 2011. Encephalitis and antibodies to synaptic and neuronal cell surface proteins. PMID: 21747075
- Zuliani L et al. J Neurol Neurosurg Psychiatry. 2012. Central nervous system neuronal surface antibody associated syndromes: review and guidelines for recognition. PMID: 22448032
- Rosenfeld MR, Dalmau J. Neurol Clin. 2018. Paraneoplastic Neurologic Syndromes. PMID: 30072076
- Balint B et al. Brain. 2018. Movement disorders with neuronal antibodies: syndromic approach, genetic parallels and pathophysiology. PMID: 29053777 Graus F et al. Neurol Neuroimmunol Neuroinflamm. 2021. Updated Diagnostic Criteria for Paraneoplastic Neurologic Syndromes. PMID: 34006622
- Scheper T et al, EUROLINE_WB allows reliable differentiation of autoantibodies against neural antigens in patients with paraneoplastic neurological syndrome, In: “From proteinomic to Molecular Epidemiology: Relevance of Autoantibodies”, 6th Dresden Symposium on Autoantibodies. 2002, Vol 3, 562-563
- Garza M, Piquet AL. Front Neurol. 2021. Update in Autoimmune Movement Disorders: Newly Described Antigen Targets in Autoimmune and Paraneoplastic Cerebellar Ataxia. PMID: 34489848
Last updated: 2024-10-22
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ENSKILD ANALYS 730
Amfifysin-antikroppar (IgG)
Indikation
Misstanke om paraneoplastiska syndrom och autoimmun encefalit
Provmaterial
Serum
- Minim. volym: 0,5 mL
Likvor
- Minim. volym: 2,0 mL
Transport
Inom Sverige
- rumstemperatur
Internationellt
- kylt
Metod
Immunoblot/Indirekt immunofluorescens (IIF)
Enligt Updated Diagnostic Criteria for Paraneoplastic Neurologic Syndromes ska anti-neuronala antikroppar detekteras med minst två oberoende metoder för att vara tillförlitliga. På Wieslab används IIF och immunoblot.
Referensintervall
Serum
- Immunoblot: <5 negativt
- Indirekt Immunofluorescens: <1:10 negativt
Likvor
- Immunoblot: negativt
- Indirekt immunofluorescens: negativt
Resultat
Serum
- Immunoblot: resultat anges som negativt, gränsvärde eller positivt med intensitetsvärde.
- Indirekt immunofluorescens: resultat anges som negativt eller positivt. Positivt resultat titreras.
Likvor
- Immunoblot: resultat anges som negativt, gränsvärde eller positivt.
- Indirekt immunofluorescens: resultat anges som negativt eller positivt.
Tolkning
Antikroppar mot Amfifysin förekommer hos patienter med den paraneoplastiska varianten av Stiff person syndrom men kan även ses vid limbisk encefalit och är associerade med bröstcancer och småcellig lungcancer. Neurologiska symtom kan föregå cancerdiagnos med upp till 5 år.
Antikropparna riktade mot Amfifysin bedöms vara High-risk antibodies med en förekomst på 80% för en underliggande cancer och positivitet ger 3 poäng i PNS score enligt Updated Diagnostic Criteria for Paraneoplastic Neurologic Syndromes.
Referenser
- Lancaster E et al. Neurology. 2011. Encephalitis and antibodies to synaptic and neuronal cell surface proteins. PMID: 21747075
- Zuliani L et al. J Neurol Neurosurg Psychiatry. 2012. Central nervous system neuronal surface antibody associated syndromes: review and guidelines for recognition. PMID: 22448032
- Rosenfeld MR, Dalmau J. Neurol Clin. 2018. Paraneoplastic Neurologic Syndromes. PMID: 30072076
- Balint B et al. Brain. 2018. Movement disorders with neuronal antibodies: syndromic approach, genetic parallels and pathophysiology. PMID: 29053777 Graus F et al. Neurol Neuroimmunol Neuroinflamm. 2021. Updated Diagnostic Criteria for Paraneoplastic Neurologic Syndromes. PMID: 34006622
- Scheper T et al, EUROLINE_WB allows reliable differentiation of autoantibodies against neural antigens in patients with paraneoplastic neurological syndrome, In: “From proteinomic to Molecular Epidemiology: Relevance of Autoantibodies”, 6th Dresden Symposium on Autoantibodies. 2002, Vol 3, 562-563
- Garza M, Piquet AL. Front Neurol. 2021. Update in Autoimmune Movement Disorders: Newly Described Antigen Targets in Autoimmune and Paraneoplastic Cerebellar Ataxia. PMID: 34489848
Senast uppdaterat: 2024-10-22
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Detta är en ackrediterad analys.> Läs mer [.pdf]
Mer information om provtagning.
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