title: Posterior reversible encephalopathy syndrome in neuromyelitis optica spectrum disorders.
abstract: 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.
authors.affiliation: Department of Neurology, Mayo Clinic College of Medicine, Rochester, MN 55905, USA.
authors.forename: S M
authors.initials: SM
authors.lastname: Magaña
authors.forename: M
authors.initials: M
authors.lastname: Matiello
authors.forename: S J
authors.initials: SJ
authors.lastname: Pittock
authors.forename: A
authors.initials: A
authors.lastname: McKeon
authors.forename: V A
authors.initials: VA
authors.lastname: Lennon
authors.forename: A A
authors.initials: AA
authors.lastname: Rabinstein
authors.forename: E
authors.initials: E
authors.lastname: Shuster
authors.forename: O H
authors.initials: OH
authors.lastname: Kantarci
authors.forename: C F
authors.initials: CF
authors.lastname: Lucchinetti
authors.forename: B G
authors.initials: BG
authors.lastname: Weinshenker
mesh_terms: D000293:Adolescent; D000328:Adult; D000906:Antibodies / Q000097:blood; D051401:Aquaporin 4 / Q000276:immunology; D015551:Autoimmunity; D001834:Body Water / Q000378:metabolism; D001921:Brain / Q000378:metabolism / Q000473:pathology; D001929:Brain Edema / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology* / Q000276:immunology / Q000523:psychology; D002561:Cerebrovascular Disorders / Q000150:complications*; D002648:Child; D015897:Comorbidity; D003221:Confusion / Q000209:etiology; D003244:Consciousness Disorders / Q000209:etiology; D038524:Diffusion Magnetic Resonance Imaging; D004305:Dose-Response Relationship, Drug; D005260:Female; D005682:Gadolinium; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000009:adverse effects; D008775:Methylprednisolone / Q000008:administration & dosage / Q000009:adverse effects; D008875:Middle Aged; D009471:Neuromyelitis Optica / Q000150:complications* / Q000276:immunology; D012075:Remission, Spontaneous; D013577:Syndrome; D013997:Time Factors; D055815:Young Adult
chemical_list: D000906:Antibodies; D051401:Aquaporin 4; D016756:Immunoglobulins, Intravenous; D005682:Gadolinium; D008775:Methylprednisolone