Abstract
RATIONALE: Myelin oligodendrocyte glycoprotein antibody-associated disorders (MOGAD) represents a demyelinating neurological syndrome characterized by the presence of serum IgG antibodies directed against myelin oligodendrocyte glycoprotein (MOG-IgG). Concurrently, giant cell arteritis (GCA) constitutes a systemic autoimmune vasculitis. PATIENT CONCERNS: In this case, we describe an elderly female patient who presented with the sudden onset of a severe headache, unilateral blindness, and clinical manifestations resembling those of GCA. DIAGNOSIS: Upon conducting a comprehensive analysis of serum antibodies, the diagnosis of MOGAD was established due to the presence of detectable serum MOG-IgG. INTERVENTIONS: Subsequently, the patient was administered intravenous methylprednisolone therapy, commencing 27 days after the initial onset of symptoms. OUTCOMES: It is noteworthy that patients afflicted by MOGAD typically manifest severe visual impairment, which, in many instances, exhibits significant improvement following immunotherapeutic interventions. However, this particular patient did not experience any amelioration in visual function despite glucocorticoid therapy. LESSONS: This unique case illustrates that the clinical presentation resembling GCA may precede the inaugural manifestation of MOGAD. This suggests the possibility of immune-mediated arterial involvement. The significance of glucocorticoid therapy in the context of immune-related diseases warrants further scrutiny, particularly in cases where MOG-IgG screening should be promptly considered.