Recurrent brainstem lesions mimicking infarctions in an elderly patient with neuromyelitis optica spectrum disorder.

Anti-aquaporin-4 (AQP4) antibody is highly specific for neuromyelitis optica (NMO) and NMO spectrum disorder. Brainstem lesions sometimes show involvement in NMO and NMO spectrum disorder, and onset is usually diagnosed in young or middle-aged adults. Here, we report the case of an 87-year-old woman with recurrent brainstem lesions and subsequent severe longitudinally extensive cervical cord lesions who was found to be positive for anti-AQP4 antibody. In patients with recurrent brainstem lesions, even in the elderly and those with symptoms mimicking infarction, NMO spectrum disorder should be considered as a differential diagnosis.