Pontine hemorrhage accompanied by neuromyelitis optica spectrum disorder

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disorder caused by antibody to aquaporin-4 (AQP4). NMOSD can infrequently present as a complication of posterior reversible encephalopathy syndrome (PRES). Moreover, few cases of NMOSD patients with brain hemorrhage have been reported. We report a rare case of PRES together with NMOSD recurrence, subsequent to pontine hemorrhage after intravenous methylprednisolone (IVMP) therapy. A 51-year-old Japanese woman, with a history of hypertension and dyslipidemia, and recurrent episodes of left visual acuity disorder related to AQP4-positive NMOSD, developed blindness in the left eye. Brain MRI showed a hyperintense lesion in pons. She was initially diagnosed with recurrence of NMOSD and 1000 mg of IVMP was administered for 3 days. After the 3rd course of IVMP, she developed left-sided sensory disturbance, and blood pressure was increased to 202/127 mmHg. Brain computed tomography (CT) showed pontine hemorrhage, and she was referred to our hospital again. We diagnosed PRES associated with NMOSD recurrence, along with development of pontine hemorrhage induced by the increase in blood pressure resulting from IVMP. The patient was treated with nicardipine to strictly control blood pressure, and tranexamic acid and glycerol for pontine hemorrhage and PRES. We also extended IVMP for 5 consecutive days in total, followed by plasmapheresis. After therapy, blindness in the left eye improved to light perception. Collectively, anti-AQP4 antibody could induce PRES together with recurrent NMOSD, and pontine hemorrhage could thus be induced by blood pressure increases resulting from IVMP.