Ophthalmoplegia in Powassan encephalitis

Powassan encephalitis, a rare arthropod-borne infection, is being increasingly recognized in New England, four cases having recently been reported.1 We describe an unusual ophthalmoplegia in one of these patients. In September 2000, a 53-year-old woman residing in Maine developed nausea, vomiting, diarrhea, dizziness, diplopia, and incoordination followed within days by arm weakness, urinary retention, fever, delirium, and almost total ophthalmoplegia. Her pupils were 2 mm and weakly reactive. There was no history of a rash or tick bite. A head CT scan was normal. MRI showed a tiny focus of signal hyperintensity in the white matter of each temporal lobe. Her erythrocyte sedimentation rate was normal, and her white …