[Failure of rituximab in relapsing neuromyelitis optica: case report with two-year prospective follow-up].

Neuromyelitis optica (Devic's disease, NMO) is an inflammatory disease of the central nervous system preferentially involving the spinal cord and optic nerves in either a monophasic or relapsing-remitting course. B-cell induced pathogenesis was recently described for NMO. Rituximab is a chimeric monoclonal antibody directed against the CD20 antigen, which causes depletion of B-cells. Rituximab might be effective in treatment of NMO. We report the two-year clinicoradiological and biological follow-up data from a patient included in July 2005 in a prospective trial of rituximab for severe NMO refractory to immunosuppressant therapy. Blood B-cell depletion after rituximab induction was maintained for 10 months. Seven attacks occurred during a two-year follow-up. EDSS increased from 7.0 to 8.0. Left visual acuity decreased from 20/20 degrees to 20/60 degrees. Spinal cord atrophy worsened.