Late onset neuromyelitis optica mimicking an acute stroke in an elderly patient.

Neuromyelitis optica spectrum disorder (NMOSD) was recently proposed as a unifying term for Neuromyelitis optica (NMO) and related syndromes to incorporate patients with NMO antibody but without the full clinical spectrum. NMO is a rare, demyelinating condition which predominantly affects females with a peak incidence in the third and fourth decade of life. We report a case of NMOSD in an elderly patient with extremely late onset (>80years) of disease. The patient presented with findings of sudden onset unilateral symptoms, which is extremely unusual for NMOSD. She had frequent relapses which were treated with high dose steroids and plasmapheresis but has not had any relapse since being started on immunosuppressive therapy and continues to do well. Our case also highlights the varied clinical presentations of NMOSD and we believe that the diagnosis of NMOSD should be considered in elderly patients in the appropriate clinical setting despite the presence of unconventional symptoms.