Objective:Longitudinally extensive transverse myelitis (LETM) could be seen in patients with connective tissue disease (CTD), especially systemic lupus erythematosus (SLE) or primary Sj?gren′s syndrome (pSS). Some patients are combined with neuromyelitis optica spectrum disorders (NMOSD)(termed CTD-LETM-NMOSD) while others without (termed CTD-LETM-non-NMOSD). The aim of this study is to compare the clinical characteristics of CTD-LETM-NMOSD patients to CTD-LETM-non-NMOSD patients.Methods:We retrospectively collected data from 40 CTD patients with LETM who were admitted to the Department of Neurology or Rheumatology at Peking Union Medical College Hospital from Jan, 2006 to Dec, 2016. They were divided into CTD-LETM-NMOSD and CTD-LETM-non-NMOSD two groups. Demographic characteristics, clinical and laboratory features were obtained from the database. Relapse rates and clinical outcome were analyzed by Kaplan-Meier method.Results:Among 40 patients with CTD, 28 (70.0%) were NMOSD while 12 (30.0%) were not. The positivity rates of anti-SSA, antibodies to aquaporin-4 (anti-AQP4) were significantly higher in patients with NMOSD than those in patients with non-NMOSD ( P<0.05). Age, gender, clinical features, disease duration, anti-double-stranded DNA antibody, anti-ribosomal P antibody, antiphospholipid antibodies, expanded disability status scale (EDSS) scores, and magnetic resonance imaging (MRI) features were all comparable between two groups. CTD-NMOSD patients had significantly higher disease relapse rate (75.0% vs. 3/12, P<0.01). Conclusion:Anti-SSA and anti-AQP4 positivity is associated with NMOSD and higher relapse rates, which suggests that NMOSD in CTD-LETM patients may represent distinct characteristics and pathogenesis from patients with CTD-LETM-non NMOSD.

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.