Therapeutic efficacy of double filtration plasmapheresis in patients with anti-aquaporin-4 antibody-positive multiple sclerosis.

Multiple sclerosis (MS) in Asian countries, including Japan, is classified into two types: conventional MS (C-MS), characterized mainly by cerebral lesions, and opticospinal MS (OS-MS) or neuromyelitis optica (NMO), characterized by selective involvement of the optic nerve and spinal cord. Recently, a serum immunoglobulin-G-antibody was discovered in patients with NMO that targets aquaporin-4 (AQP4). The existence of the anti-AQP4 antibody shows the pathogenetic role of humoral immune factors in OS-MS/NMO. We treated eight patients with anti-AQP4 antibody-positive MS with double filtration plasmapheresis (DFPP) to remove the antibody. Improvement of vision was observed in two patients. Motion improvement was seen in seven patients. Sensory improvement was observed in four patients. In total, six out of eight patients (75%) showed therapeutic improvement after DFPP treatment. We propose that DFPP might be an effective therapeutic option for patients with anti-AQP4 antibody-positive MS.