A case of neuromyelitis optica spectrum disorder following seasonal influenza vaccination

•The infections or vaccine may be a trigger for the autoimmune response of NMOSD•There have been cases of NMOSD associated with exposure to various vaccines.•We present a woman who developed longitudinally extensive transverse myelitis with anti-aquaporin 4 antibody following influenza vaccination.•Vaccines may accelerate the shift to overt disease in patients with subclinical autoimmune disease. There have been reports of central nervous systemic inflammatory disease associated with vaccination. We describe a female patient who developed longitudinally extensive transverse myelitis following seasonal influenza vaccination. A 38-year-old woman had severe neck and back pain with urinary retention. She received influenza vaccine 3 days before symptom onset. Examination revealed mild quadriparesis with diffuse hyperreflexia. Magnetic resonance imaging (MRI) of the spine showed a T2 hyperintense lesion with gadolinium enhancement in the spinal cord extending from the cervicomedullary junction to the level of T10. Brain MRI revealed no specific finding for demyelinating lesions. Cerebrospinal fluid had a white blood cell count of 60/L (mononuclear cells 95%) with a protein concentration of 78.2 mg/dL and the blood serum was positive for anti-aquaporin-4 antibodies. She was treated with high-dose methylprednisolone for 5 days followed by tapering of prednisolone. Symptoms improved significantly after treatment. We report a case of neuromyelitis optica spectrum disorder following seasonal influenza vaccination. Neuromyelitis optica spectrum disorder may have been triggered by the recent influenza vaccination, although a pathogenic link has not been established.