Efgartigimod as adjunctive therapy for immunotherapy-dependent autoimmune diencephalitis

Rationale: Autoimmune diencephalitis is a rare neurological disorder. Our hospital recently admitted a case of immunotherapy-dependent autoimmune diencephalitis. The patient showed significant improvement after adjunctive treatment with efgartigimod, providing new insights into the treatment of autoimmune diencephalitis. Patient concerns: The patient, a middle-aged male, presented with acute onset of symptoms lasting more than 3 months, including intermittent headache, fever, epileptic seizures, and impaired consciousness. Diagnoses: Laboratory tests and magnetic resonance imaging confirmed autoimmune diencephalitis. Interventions: The patient was treated with glucocorticoids, intravenous immunoglobulin, mycophenolate mofetil, and efgartigimod. Outcomes: After the addition of efgartigimod, glucocorticoid tapering was successfully achieved, and the patient gradually recovered. Lessons: This case demonstrates the favorable effect of efgartigimod as an adjunctive therapy for autoimmune diencephalitis, effectively controlling symptoms and improving patient prognosis.