Therapeutic apheresis for neuromyelitis optica and neuromyelitis optica spectrum disorders

Abstract

Neuromyelitis optica (NMO) was considered an atypical type of multiple sclerosis (MS). Now, NMO is distinguished from MS with regard to the presence of anti-aquaporin-4 antibody, and this antibody shows a pathogenetic role in the humoral immune mechanism of NMO. Steroids are a better therapeutic option during NMO attacks, although they are occasionally refractory, and plasma exchange is subsequently introduced. We treated 3 patients with NMO and 7 patients with NMO spectrum disorders (5 patients with optic neuritis and 2 with myelitis) as follows: 1 patient was treated with plasma exchange (PE); 4 with double-filtration plasmapheresis (DFPP); and 5 with immunoadsorption plasmapheresis (IAPP). The exchanged volume in PE and DFPP was equivalent to the estimated plasma volume. In IAPP, 1.5L of plasma was processed according to the manufacturer's instructions. The apheresis therapies were repeated 4.9 times on average. The interval from the onset of symptoms to initiation of apheresis therapy was 40 days in 8 patients, and their symptoms improved after the therapy. In the remaining 2 patients, the therapy was initiated on days 53 and 120 after the onset of symptoms, but they did not improve after the therapy. We propose that DFPP and IAPP are beneficial therapeutic options for inducing clinical remission in steroid-refractory cases of NMO and NMO spectrum disorders.