MOGAD-Associated Recurrent Optic Neuritis Unresponsive to Corticosteroids: Clinical, Visual Field, and OCT Correlation.

Background: Myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) is a rare autoimmune demyelinating disorder. In adults, optic neuritis is the most common initial manifestation. Case presentation: We report the case of a 23-year-old woman presenting with right eye vision loss and severe optic disc edema. The condition was unresponsive to intravenous corticosteroids. Plasmapheresis led to marked improvement. Two months later, a second episode occurred in the left eye, despite ongoing steroid therapy. Investigations: Initial brain and orbital MRI were normal. Optical coherence tomography (OCT) showed increased RNFL thickness in the acute phase and progressive thinning during follow-up. Anti-MOG antibodies were detected at a 1:100 titer in serum, confirming the diagnosis. Treatment and outcome: The patient was treated with plasmapheresis, oral steroids, and azathioprine during the first attack. After the second relapse, rituximab was initiated. The patient achieved visual recovery and has remained relapse-free for two years. Conclusion: Corticosteroid-unresponsive recurrent optic neuritis should prompt evaluation for MOGAD, especially in the presence of bilateral involvement and optic disc edema. OCT is valuable for monitoring disease activity and structural damage.