Complete Relief of Painful Tonic Seizures in Neuromyelitis Optica Spectrum Disorder by Satralizumab Treatment

Satralizumab, a monoclonal antibody against interleukin-6 receptors, has been approved for the treatment of neuromyelitis optica spectrum disorder (NMOSD). Several reports have described the effectiveness of satralizumab against neuropathic pain in patients with NMOSD, but its effects on painful tonic seizures have not yet been reported. We herein report a Japanese woman with anti-aquaporin-4 antibody-positive NMOSD whose painful tonic seizures completely resolved after six months of satralizumab treatment. In conclusion, interleukin-6 blocking may be effective against painful tonic seizures. This effect may be due to suppression of microglial activation and the resultant neuronal hyperexcitability.