RESUMO
A twelve-year-old African-American female presented with two week history of progressively worsening headache and fatigue, and vision difficulties for the past week. The physical examination was normal. The neurological evaluation was normal, except for cranial nerves (CN) testing, which showed bilateral restriction of adduction (CN III) and up gaze (CN IV) motions, vertical nystagmus, and left side facial paresis of central origin (CN VII). The bilateral exotropia and ophthalmoplegia are characteristics of WEBINO (Wall-Eyed Bilateral Intranuclear Ophthalmoplegia) syndrome, associated to a brain stem structural lesion. The following causes were evaluated and ruled out: tumor, infection, ischemic stroke, non-infectious inflammation. Pediatric Acquired Demyelinating Syndromes were then considered. Neuromyelitis Optica was ruled out in the absence of neuritis and normal spinal cord MRI. The differential diagnosis between Clinically Isolated Syndrome and Acute Demyelinating Encephalomyelitis, causing an isolated brain stem syndrome, is discussed.