title: Adult onset chronic unihemispheric vasculitis resembling Rasmussen encephalitis.
abstract: BACKGROUND
  Rasmussen encephalitis (RE), a chronic inflammatory unilateral brain disease, is usually associated with intractable seizures and progressive neurologic deterioration. Despite being initially observed in children, an adult form has been more recently recognized. MRI discloses progressive atrophy and signal changes through the affected hemisphere, but rarely gadolinium enhancement, which when observed requires a brain biopsy to distinguish Rasmussen encephalitis from an alternative diagnosis as unihemispheric vasculitis.
  
  
  METHODS
  An adult patient had at the age of 35 his first generalized seizure followed by transient right hemiparesis and aphasia. Two years later, seizures relapsed with a gradually increasing frequency associated with progressive neurologic deterioration. Repeated brain imaging, revealed progressive atrophy and signal changes within the left hemisphere with gadolinium enhancement. Histopathology disclosed focal gliosis mainly in white matter and some small intraparenchymal arteries, and arterioles with perivascular and intramural chronic inflammatory cell infiltrate.
  
  
  CONCLUSIONS
  Unihemispheric chronic vasculitis may resemble adult-onset Rasmussen encephalitis, and persistent gadolinium enhancement seen on MRI lesions is helpful for the differential diagnosis between the 2 conditions.
authors.affiliation: Department of Neurology, School of Medicine, State University of Campinas, Campinas, Brazil. alfredodamasceno@hotmail.com
authors.forename: Alfredo
authors.initials: A
authors.lastname: Damasceno
authors.forename: Marcondes
authors.initials: M
authors.lastname: França
authors.forename: Luciano Souza
authors.initials: LS
authors.lastname: Queiroz
authors.forename: Fernando
authors.initials: F
authors.lastname: Cendes
authors.forename: Anamarli
authors.initials: A
authors.lastname: Nucci
authors.forename: Benito Pereira
authors.initials: BP
authors.lastname: Damasceno
mesh_terms: D000328:Adult; D017668:Age of Onset; D001921:Brain / Q000473:pathology; D002561:Cerebrovascular Disorders / Q000175:diagnosis* / Q000473:pathology*; D002908:Chronic Disease; D003937:Diagnosis, Differential; D004660:Encephalitis / Q000175:diagnosis*; D007839:Functional Laterality; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D014657:Vasculitis / Q000175:diagnosis* / Q000473:pathology*