Anti-Aquaporin-4 Antibody-Positive Optic Neuritis Treated with Double-Filtration Plasmapheresis

Purpose: The anti-aquaporin-4 (AQP4) antibody was recently reported to be associated with neuromyelitis optica (NMO). Optic nerve involvements in many NMO cases are bilateral and the prognosis is poor. However, it has been suggested that plasma exchange is effective for those patients when steroid pulse therapy is ineffective. Herein, we report successful treatment of a patient with NMO using double-filtration plasmapheresis (DFPP). Case: A 22-year-old woman consulted a neurologist for neck pain in March 2008. High-intensity lesions were shown in the cervical spinal cord by T2-weighted magnetic resonance imaging. On July 15, the patient was referred to our department for a headache and pain and blurred vision in the left eye. The best-corrected visual acuity was 20/50 and 20/500 in the right and left eyes, respectively, with visual field defects observed in both. After 3 courses of steroid pulse therapy, anti-AQP4 antibodies were positive. In November, the patient again noticed visual acuity loss in the left eye and was treated by additional steroid pulse therapy, which was not effective. Next, she underwent plasma exchange therapy, though it was stopped due to hypotension and dyspnea. The next day, the patient underwent DFPP treatment and visual function gradually recovered. Conclusion: It is important to consider NMO when steroid pulse therapy is not effective. We successfully and safely treated NMO in a young adult patient using DFPP.