A case of neuromyelitis optica harboring both anti-aquaporin-4 antibodies and a pathogenic mitochondrial DNA mutation for Leber's hereditary optic neuropathy.

We report the first case of definite neuromyelitis optica (NMO) with a pathogenic mitochondrial DNA (mtDNA) mutation for Leber's hereditary optic neuropathy (LHON) (G11778A point mutation). A 36-year-old Japanese woman had experienced recurrent neurological symptoms originating from involvements of the optic nerves and spinal cord. She finally lost her bilateral vision, and spastic paraparesis and sensory disturbances below the T6 level remained despite intensive immunotherapies. Brain and spinal magnetic resonance imaging (MRI) revealed T2-high-intensity lesions in the optic nerves and thoracic spinal cord, but no lesions in the brain. A blood examination revealed positivity for both anti-aquaproin-4 antibodies and an LHON mtDNA mutation.