Anti-GluK2 antibody-associated autoimmune encephalomyelitis with delayed MRI abnormalities: case report.

To present the first documented case of delayed radiological manifestation in a patient with anti-GluK2 antibody-associated autoimmune encephalomyelitis, and to highlight the clinical significance of this rare yet potentially treatable disorder. We presented a 20-year-old woman with seizures, dizziness, limb weakness and numbness, gait instability, and bladder and bowel dysfunction. Comprehensive evaluations were performed, including blood and cerebrospinal fluid (CSF) analyses (with autoimmune antibody panels), electroencephalography (EEG), and serial brain and spinal cord magnetic resonance imaging (MRI). The patient received intravenous methylprednisolone combined with immunoglobulin therapy. The patient was diagnosed with anti-GluK2 antibody-associated autoimmune encephalomyelitis. Initial brain and spinal cord magnetic resonance imaging (MRI) examinations performed at disease onset yielded unremarkable findings. Notably, despite clinical improvement following immunotherapy, novel radiological abnormalities emerged one month later, underscoring the characteristic delayed MRI manifestation of this condition. This case suggests that anti-GluK2 antibody-associated encephalomyelitis may present with delayed spinal MRI findings despite early normal imaging. Elevated serum IgE may be involved in pathogenesis. Early diagnosis and immunotherapy appear critical for clinical improvement.