Satralizumab effectively relieves refractory painful tonic spasms in AQP4-positive NMOSD presenting as meningomyelitis

Neuromyelitis optica spectrum disorder (NMOSD) can rarely present with meningitis-like features and painful tonic spasms (PTS). We report a case of aquaporin-4 (AQP4) antibody-positive NMOSD combined with latent Epstein–Barr virus (EBV) infection, successfully treated with Satralizumab. A 50-year-old previously healthy woman developed fever, followed by bilateral lower limb paresthesia and urinary retention. Clinical features and cerebrospinal fluid pleocytosis initially mimicked bacterial meningomyelitis. MRI revealed lesions in the meninges and spinal cord. Anti-AQP4 antibodies were positive (titer 1:32). She responded promptly to initial immunotherapy. One month later, she developed PTS, initially treated with antiepileptic drugs, which were discontinued due to suspected hypersensitivity. Satralizumab therapy was initiated, resulting in complete PTS resolution within two months. This case presents a speculative hypothesis that latent EBV infection may be associated with AQP4-positive NMOSD presenting with meningitis-like features and refractory PTS. Satralizumab may offer an effective therapeutic option for managing PTS in NMOSD.