Pathogenesis of aquaporin-4 immunoglobulin G positive neuromyelitis optica spectrum disorder / 中华神经科杂志

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune demyelinating disease of the central nervous system characterized by the involvement of the optic nerve and spinal cord. The main clinical features are optic neuritis, acute myelitis, and area postrema syndrome. Aquaporin-4 (AQP4)-IgG-positive patients accounted for the majority and compared with AQP4-IgG-negative patients, the clinical symptoms were more severe, the recurrence was more frequent, and the disability rate was higher. The pathogenesis of AQP4-IgG-positive NMOSD is still not clear. This article reviews the research progress of the pathogenesis of AQP4-IgG-positive NMOSD.

Relapse risk analysis in anti-aquaporin 4-IgG positive neuromyelitis optica spectrum disorders patients treated with immunosuppressant / 中华神经科杂志

Objective:To investigate the relapse risk factors of anti-aquaporin 4 (AQP4)-IgG positive neuromyelitis optica spectrum disorders (NMOSD) patients treated with immunosuppressant.Methods:Data (from January 2011 to June 2021) of AQP4-IgG positive NMOSD patients treated with immunosuppressant for longer than 5 years from MSNMObase, a hospital-based electronic registry for multiple sclerosis and related disorders in Peking Union Medical College Hospital, were collected. Clinical features and risk factor differences between patients with and without relapse under the immunosuppressive therapy were analyzed.Results:One hundred and twelve patients with AQP4-IgG positive NMOSD were included, 105 (93.8%) of which were female. The disease onset age was (34.9±11.3) years, 13(11.6%) had an older disease onset age than 50 years (late onset), and the disease duration was 8.1 (6.6, 11.4) years. Sixty-four (57.1%) patients had relapse, and the proportion of late onset patients was significantly lower in relapse group than in non-relapse group [4/64(6.3%) vs 9/48(18.8%), χ2=4.18, P=0.041]. Compared with those without relapse, both the annualized relapse rate (ARR) before treatment [1.07 (0.36, 2.25) vs 0.34 (0, 1.11), Z=2.92, P=0.003] and the proportion of patients with relapse before treatment [54/64(84.4%) vs 33/48(68.8%), χ2=3.86, P=0.049] were significantly higher for patients in relapse group. Multivariate Logistic regression analysis revealed the relapse risk of late-onset patients was lower than that of early-onset patients ( HR=0.26, 95% CI 0.10-0.73, P=0.010) and patients with higher ARR before treatment showed a higher risk of relapse under the immunosuppressive therapy ( HR=1.55,95% CI 1.26-1.91, P<0.001). Conclusion:AQP4-IgG positive NMOSD patients with younger disease onset age than 50 years or with frequent relapses before treatment had a higher relapse risk under the immunosuppressive therapy, and they may need highly effective treatments.