Extremely Longitudinally Extensive Transverse Myelitis in a Patient with Myelin Oligodendrocyte Glycoprotein Antibody-Associated Disease

Longitudinally extensive myelitis with 15 or more vertebrae in length is extremely rare, with limited evidence regarding clinical features and therapeutic response.We report a case of a 29-year-old male patient with extremely longitudinally extensive myelitis ultimately diagnosed as myelin oligodendrocyte glycoprotein-associated disease (MOGAD).The patient presented with an acute onset of meningismus, limb weakness, sensory disturbance below the C5 level, ataxia, and urinary retention.T2-weighted imaging on MRI showed an extremely longitudinally extensive spinal cord lesion ranging from C2 to the medullary conus, together with a left pontine lesion.Positive anti-myelin oligodendrocyte glycoprotein antibodies were serologically detected, which led to the diagnosis of MOGAD.Intravenous methylprednisolone followed by 1 mg/kg oral prednisolone with taper resulted in complete symptomatic and radiological resolution.The striking complete resolution despite the symptomatic and radiological severity observed in this case has been described in a few previously reported MOGAD cases.Extremely longitudinally extensive myelitis with excellent therapeutic response may be a characteristic presentation of MOGAD.