Concomitant abducens and facial nerve palsies: A rare presentation in anti-aquaporin-4 antibody-positive neuromyelitis optica

Over the past decade, the discovery of disease-specific aquaporin-4 antibodies has led to a better understanding of the diverse spectrum of disorders that are associated with neuromyelitis optica. Brainstem manifestations have been increasingly recognized in this disease. However, multiple cranial nerve palsies as an initial presentation of neuromyelitis optica are uncommon. We report a rare case of anti-aquaporin-4 antibody-positive neuromyelitis optica that presented with unilateral abducens and facial nerve palsies. Notably, this case did not involve the optic nerve or the spinal cord. Diagnosing neuromyelitis optica that presents as an isolated acute brainstem syndrome is challenging, but the outcome may be devastating if the diagnosis is delayed.