RT Journal Article SR Electronic T1 Posterior reversible encephalopathy syndrome in neuromyelitis optica spectrum disorders JF Neurology JO Neurology FD Lippincott Williams & Wilkins SP 712 OP 717 DO 10.1212/01.wnl.0000343001.36493.ae VO 72 IS 8 A1 S. M. Magaña A1 M. Matiello A1 S. J. Pittock A1 A. McKeon A1 V. A. Lennon A1 A. A. Rabinstein A1 E. Shuster A1 O. H. Kantarci A1 C. F. Lucchinetti A1 B. G. Weinshenker YR 2009 UL http://n.neurology.org/content/72/8/712.abstract AB Background: Posterior reversible encephalopathy syndrome (PRES) is characterized by vasogenic subcortical edema without infarction. It has been associated with hypertensive crises and with immunosuppressive medications but not with neuromyelitis optica (NMO). Methods: We reviewed the clinical and neuroimaging features of five NMO–immunoglobulin G (IgG) seropositive white women who experienced an episode of PRES and had a coexisting NMO spectrum disorder (NMOSD). We also tested for the aquaporin-4 (AQP4) water channel autoantibody (NMO-IgG) in 14 patients from an independently ascertained cohort of individuals with PRES. Results: All five patients developed abrupt confusion and depressed consciousness consistent with PRES. The encephalopathy resolved completely within 7 days. Comorbid conditions or interventions recognized to be associated with PRES included orthostatic hypotension with supine hypertension, plasma exchange, IV immunoglobulin treatment, and high-dose IV methylprednisolone. Brain MRI studies revealed bilateral T2-weighted (T2W) hyperintense signal abnormalities, primarily in frontal, parieto-occipital, and cerebellar regions. Three patients had highly symmetric lesions and three had gadolinium-enhancing lesions. Follow-up neuroimaging revealed partial or complete disappearance of T2W hyperintensity or gadolinium-enhancing lesions in all five patients. Patients with PRES without NMOSD were uniformly NMO-IgG seronegative. Conclusions: Brain lesions in some patients with neuromyelitis optica spectrum disorder (NMOSD) may be accompanied by vasogenic edema and manifest as posterior reversible encephalopathy syndrome (PRES). Water flux impairment due to aquaporin-4 autoimmunity may predispose to PRES in patients with NMOSD who experience blood pressure fluctuations or who are treated with therapies that can cause rapid fluid shifts. ADC = apparent diffusion coefficient; AQP4 = aquaporin-4; DWI = diffusion-weighted imaging; FLAIR = fluid-attenuated inversion recovery; Gd = gadolinium; IgG = immunoglobulin G; IVIg = IV immunoglobulin; IVMP = IV methylprednisolone; LETM = longitudinally extensive transverse myelitis; NMO = neuromyelitis optica; NMOSD = neuromyelitis optica spectrum disorder; ON = optic neuritis; PLEX = plasma exchange; PRES = posterior reversible encephalopathy syndrome; T2W = T2-weighted.