INDIVIDUAL TEST 880

Aquaporin 4 (AQP4) Antibodies  (IgG)

Indication

Suspicion of Neuromyelitis Optica Spectrum Disorder (NMOSD)

Sample material

Serum

• Minim. volume: 0,5 mL

CSF

• Minim. volume: 0,5 mL

Transport

Within Sweden

• room temperature

International

• cold

Method

Cell-based assay (CBA), indirect immunofluorescence (IIF)

Reference interval

• Serum: <1:10 negative
• CSF: negative

Result

Results are reported as negative or positive. A positive result is followed by a titer (serum).

Interpretation

IgG antibodies against AQP4 are a strong marker for Neuromyelitis optica spectrum disorder (NMOSD).

If clinical suspicion of NMOSD remains after a negative result, complementary analysis with live Cell Based Assay (live CBA) is recommended in serum.

The recommendation is to test for anti-AQP4 antibodies only in serum, but there are isolated cases where anti-AQP4 antibodies have only been detected in CSF. The clinical relevance of antibodies in CSF is unclear and the diagnostic criteria are based on analysis of serum.

References

• Sato DK et al. Neurology. 2014. Distinction between MOG antibody-positive and AQP4 antibody-positive NMO spectrum disorders. PMID: 24415568
• Reindl M et al. Neurol Neuroimmunol Neuroinflamm. 2020. International multicenter examination of MOG antibody assays. PMID: 32024795
• Majed M et al. Neurol Neuroimmunol Neuroinflamm. 2016. Clinical utility of testing AQP4-IgG in CSF: Guidance for physicians. PMID: 27144221
• Höftberger R et al. Mult Scler. 2015. Antibodies to MOG and AQP4 in adults with neuromyelitis optica and suspected limited forms of the disease. PMID: 25344373
• Wingerchuk DM et al. Neurology. 2015. International consensus diagnostic criteria for neuromyelitis optica spectrum disorders. PMID: 26092914
• Lycke J, Malmeström C. Lakartidningen. 2010. Neuromyelitis optica--viktig differentialdiagnos till MS. Tidigt insatt behandling avgörande för prognosen. PMID: 21294335
• Banwell B et al. Lancet Neurol. 2023. Diagnosis of myelin oligodendrocyte glycoprotein antibody-associated disease: International MOGAD Panel proposed criteria. PMID: 36706773
• Paul F et al. Neurol Neuroimmunol Neuroinflamm. 2023. International Delphi Consensus on the Management of AQP4-IgG+ NMOSD: Recommendations for Eculizumab, Inebilizumab, and Satralizumab. PMID: 37258412
• Petzold A et al. Lancet Neurol. 2022. Diagnosis and classification of optic neuritis. PMID: 36179757

Last updated: 2025-03-18