Compared with the control group (median, 75.16 pg/ml; range, 27.70–279.71), the serum CXCL13 levels were higher in patients with NMO (median, 156.32 pg/ml; range, 46.88–398.22) (Z = −3.298, p = .001), and they also had a higher trend than those of MS patients (median, 90.52 pg/ml; range, 36.50–530.94) (Z = −1.650, p = .099). This evidence concerns the gene CXCL13 and neuromyelitis optica.