Comparison of clinical and laboratory characteristics of neuromyelitis optica spectrum disorder with or without anti-connective tissue antibodies: an 18-month cohort follow-up.

Purpose: This study aimed to explore the significance of anti-connective tissue antibodies in the clinical diagnosis and evaluation of neuromyelitis optica spectrum disorder (NMOSD). Methods: Demographic and clinical data from 205 patients with aquaporin-4 immunoglobulin G (AQP4-IgG)-positive NMOSD were collected. Variables included sex, age, clinical symptoms/signs, connective tissue antibody status, inflammatory markers, cerebrospinal fluid (CSF) cell counts/oligoclonal band status, spinal cord lesion location/length, Expanded Disability Status Scale scores at onset and first relapse (18-month follow-up), and time to first relapse. Results: Among the 205 patients, 108 (52.7%) were positive for anti-connective tissue antibodies (CTD abs+). Compared with anti-connective tissue antibodies (CTD abs-) patients, the CTD abs+ group had higher lymphocyte counts (1.82 ± 0.14 vs. 1.73 ± 0.07, Conclusions: In summary, among AQP4-IgG-positive patients with NMOSD, CTD abs+ was associated with higher lymphocyte counts, a higher MLR, higher CSF white blood cell counts, higher CSF immunoglobulin levels, a higher 24-hour intrathecal IgG synthesis rate, and higher OCB positivity. CTD abs positivity may therefore indicate a more severe inflammatory profile; however, it does not appear to predict earlier relapse, but does appear to predict a higher annualized relapse rate.