Relapsing neuromyelitis optica spectrum disorder due to noncompliance to oral corticosteroid therapy

<jats:sec> <jats:title>Rationale:</jats:title> <jats:p>Neuromyelitis optica (NMO) is an inflammatory, demyelinating disease of the central nervous system characterized by severe optic neuritis and myelitis. NMO recurrence can be triggered by infection, pregnancy, and the tapering of oral corticosteroid medication.</jats:p> </jats:sec> <jats:sec> <jats:title>Patient concerns:</jats:title> <jats:p>A 14-year-old girl with no remarkable birth or developmental history was admitted to our hospital after experiencing visual loss in the right eye. The right eye was positive for relative afferent pupillary defects.</jats:p> </jats:sec> <jats:sec> <jats:title>Diagnosis:</jats:title> <jats:p>Orbital magnetic resonance imaging revealed a high-intensity area in the right optic nerve. Serum levels of anti–aquaporin 4 (AQP4) antibodies were high. She was diagnosed with anti-AQP4 antibody-positive right-sided optic neuritis.</jats:p> </jats:sec> <jats:sec> <jats:title>Interventions:</jats:title> <jats:p>Her symptoms improved after repeated intravenous methylprednisolone pulse therapy and intravenous immunoglobulin therapy. Subsequently, she continued to take oral steroids as a long-term preventive measure.</jats:p> </jats:sec> <jats:sec> <jats:title>Outcomes:</jats:title> <jats:p>She relapsed twice, at the ages of 14 and 16 years, due to nonadherence to oral corticosteroid medication at her discretion (fears of steroid side effects and worsening infection without other causes), with anti-AQP4 antibody-positive NMO leading to multiple lesions in the cerebral cortex.</jats:p> </jats:sec> <jats:sec> <jats:title>Lessons:</jats:title> <jats:p>To our knowledge, this is the first report of NMO with increasing recurrence severity due to nonadherence to oral corticosteroid medication. This case demonstrates the importance of oral corticosteroid therapy in preventing relapses of anti-AQP4 antibody-positive NMO and suggests the need to educate patients regarding steroid therapy.</jats:p> </jats:sec>