Neuromyelitis optica: The clinical role of the anti–aquaporin 4 autoantibody

Neuromyelitis optica, also known as Devic’s disease, involves inflammation of the optic nerve and the spinal cord. It runs a variable clinical course and may result in blindness. Unlike multiple sclerosis, neuromyelitis optica is a separate clinical entity with its own diagnostic criteria that include the presence or absence of anti–aquaporin 4 autoantibody. The effects of the disease are thought to be mediated by autoantibodies that are targeted against the water channel protein, aquaporin 4. In this case report, we highlight the clinical features and the role of this antibody in the diagnosis of patients with neuromyelitis optica.