Andreu Vilaseca, Angeliki Filippatou, Yana Said, Elia Sechi, Stephanie B. Syc-Mazurek, Laura Cacciaguerra, Kai Guo, Nisa Vorasoot, Moritz Niederschweiberer, Smathorn Thakolwiboon, Jessica A. Sagen, Sebastian A. Lopez-Chiriboga, Jan-Mendelt Tillema, John J. Chen, Sean J. Pittock, Elias S. Sotirchos, Eoin P. Flanagan
OBJECTIVES: Myelin oligodendrocyte glycoprotein (MOG) antibodies (MOG-IgG) are a biomarker of MOG antibody-associated disease (MOGAD). However, false positives remain common. We aimed to develop a scoring tool to guide interpretation. METHODS: Observational study of MOG-IgG-positive patients at Mayo Clinic (May 2022-December 2024). The primary outcome was fulfillment of 2023-MOGAD diagnostic criteria. Predictive variables were identified using logistic regression, and scoring systems were derived and evaluated using receiver operating characteristic analysis. Internal (n = 92) and external (Johns Hopkins, n = 117) validation was performed. RESULTS: isappearance ≥1 T2-lesion [+1 point]. The score showed an area under the curve (AUC) of 0.983 (95%CI 0.961-1.000). The score was validated internally (AUC = 0.976) and externally (AUC = 0.977). DISCUSSION: The TRUE-MOGAD score is a practical tool that accurately identifies MOGAD among positive MOG-IgG test results and may guide diagnostic and therapeutic decisions in clinical practice. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that a TRUE-MOGAD score of 2 or more accurately predicts MOGAD in patients with MOG-IgG titers of 1:20 or higher using the assay described.