We retrospectively evaluated the prognosis of neuromyelitis optica spectrum disorder (NMOSD) patients who underwent therapeutic apheresis following intravenous methylprednisolone (IVMP) therapy.

NMOSD is a group of autoimmune inflammatory diseases characterized by optic neuritis and myelitis. The primary treatment for acute exacerbations of NMOSD is the early initiation of IVMP therapy, and therapeutic apheresis is indicated only for treatment-resistant cases. However, at our institute, some patients with “mild NMOSD” who received apheresis showed favorable outcomes. In this observational study, we evaluated the efficacy of therapeutic apheresis in managing NMOSD. 

We extracted data from electronic medical records, including clinical courses, blood test results, and MRI findings of NMOSD patients who received therapeutic apheresis at our institute from November 2016 to December 2023. Neurological findings were evaluated retrospectively using the expanded disability status scale (EDSS) based on documented neurological symptoms in the medical records. We assessed changes in EDSS scores and the area of spinal cord lesions on MRI before and after apheresis.

Eight patients received therapeutic apheresis after IVMP therapy during the study period. Improvement in EDSS scores was observed in 7 of 8 patients, whereas 1 patient showed no change (5.5 ± 1.6 vs. 4.0 ± 2.3, p=0.007). MRI analysis revealed a significant reduction in lesion area before and after apheresis (4.21 cm² ± 3.37 vs. 1.12 cm² ± 0.657, p=0.03). A comparison between patients with lower and higher EDSS scores showed no statistically significant difference in EDSS improvement (2.0 ± 1.2 vs. 1.0 ± 0.91, p=0.10). Additionally, the reduction rate of lesion area was not significant between these groups (0.74 ± 0.15 vs. 0.57 ± 0.38, p=0.28).

The use of therapeutic apheresis in conjunction with IVMP therapy for NMOSD may have broader applications in the future.