Intravenous immunoglobulin as the rescue treatment in NMOSD patients

Intravenous immunoglobulin (IVIg) has been used for neuromyelitis optica spectrum disorder (NMOSD) patients to prevent relapses in several studies. However, efficacy of the rescue treatment of IVIG was just assessed in a small sample research. The aim of this study is to investigate the efficacy of IVIG in NMOSD as a rescue treatment and whether it could reduce the relapse rate. We retrospectively reviewed patients with NMOSD in the First and Second Affiliated Hospital of Wenzhou Medical University. Clinical parameters were extracted from the medical records, such as expanded disability scale score (EDSS) and time to next relapse. Thirty-one events of 20 NMOSD patients were included in the intravenous methylprednisolone (IVMT) + IVIG group and 72 events of 39 patients in the IVMT group. IVMT therapy combined with IVIG could improve the neurological disability when discharged (p < 0.001), whereas patients first attacked did not show a similar trend. Patients who were treated with IVMT + IVIG (17.39 ± 2.75 months) show a longer time to next relapse compared to patients who were treated with IVMT (9.50 ± 0.79 months) (log rank test p = 0.002), especially in relapsed patients or anti-aquaporin-4 antibody (AQP4-Ab) seropositive patients. IVIG might be helpful for NMOSD patients as the rescue treatment and might bring a longer remission, especially for patients with relapse and AQP4-ab seropositive patients.