Diagnostic value of aquaporin-4-IgG live cell based assay in neuromyelitis optica spectrum disorders

• Published in: Multiple sclerosis journal - experimental, translational and clinical Vol. 7; no. 4; p. 20552173211052656
• Main Authors: Redenbaugh, Vyanka, Montalvo, Mayra, Sechi, Elia, Buciuc, Marina, Fryer, James P., McKeon, Andrew, Lennon, Vanda A., Mills, John R., Weinshenker, Brian G., Wingerchuk, Dean M., Chen, John J., Tariq Bhatti, M., Lopez Chiriboga, A. Sebastian, Pittock, Sean J., Flanagan, Eoin P.
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01-10-2021; Sage Publications Ltd
• Subjects: Aquaporins; Brief Report
• ISSN: 2055-2173; 2055-2173
• DOI: 10.1177/20552173211052656

Objective
Determine the utility of aquaporin 4 IgG (AQP4-IgG) testing (live cell-based assay) for Neuromyelitis Optica Spectrum Disorders (NMOSD).
Methods
We included Mayo Clinic patients (1/1/2018-12/31/2019) tested for serum AQP4-IgG by live cell-based flow-cytometric assay. Medical records were reviewed to assess if patients fulfilled 2015 NMOSD criteria.
Results
Of 1371 patients tested, 41 were positive (3%) and all fulfilled NMOSD criteria with AQP4-IgG (specificity = 100%). Only 10/1330 testing negative met NMOSD criteria without AQP4-IgG (sensitivity = 80%) and seven of these 10 were MOG-IgG positive.
Conclusions
AQP4-IgG by live cell-based assay was highly specific and without false positives in a high throughput setting.