Neuromyelitis optica spectrum disorder presenting in an octogenarian

This case describes an 81-year-old woman with a history of Sjögren's syndrome presenting with recurrent falls and poor balance. She subsequently developed new and rapidly evolving neurology including hyperaesthesia, spastic paraplegia and sphincteric dysfunction. Following serial clinical reviews and detailed investigations, MRI (brainstem and cervicothoracic spine) and a seropositive result for aquaporin 4 IgG, a diagnosis of neuromyelitis optica spectrum disorder (NMOSD) was made. This case describes the clinical course of this index patient with an unusual late age of onset. The report also includes a discussion on NMOSD. We review aspects of terminology, brief epidemiology, pathogenesis, notable autoimmune associations, variance in clinical presentation and current diagnostic criteria. We also review the importance of distinguishing NMOSD from multiple sclerosis in view of the significant implications for treatment and prognosis.