title: Multiple sclerosis with predominant, severe cognitive impairment.
abstract: OBJECTIVE
  To describe the characteristics of multiple sclerosis (MS) presenting with severe cognitive impairment as its primary disabling manifestation.
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  Tertiary referral center. Patients Patients were identified through the Mayo Clinic data retrieval system (1996-2008) with definite MS (McDonald criteria) and severe cognitive impairment as their primary neurological symptom without accompanying significant MS-related impairment or alternative diagnosis for cognitive dysfunction. Twenty-three patients meeting inclusion criteria were compared regarding demographics, clinical course, and radiological features.
  
  
  METHODS
  Demographic, clinical, and radiological characteristics of the disease.
  
  
  RESULTS
  Twelve patients were men. The median age of the first clinical symptom suggestive of central nervous system demyelination was 33 years, and severe MS-related cognitive impairment developed at a median age of 39 years. Cognitive impairment could be dichotomized as subacute fulminant (n = 9) or chronic progressive (n = 14) in presentation, which corresponded to subsequent relapsing or progressive MS courses. Study patients commonly exhibited psychiatric (65%), mild cerebellar (57%), and cortical symptoms and signs (eg, seizure, aphasia, apraxia) (39%). Fourteen of 21 (67%), where documented, smoked cigarettes. Brain magnetic resonance imaging demonstrated diffuse cerebral atrophy in 16 and gadolinium-enhancing lesions in 11. Asymptomatic spinal cord magnetic resonance imaging lesions were present in 12 of 16 patients (75%). Immunomodulatory therapies were generally ineffective in improving these patients.
  
  
  CONCLUSIONS
  We describe patients with MS whose clinical phenotype is characterized by severe cognitive dysfunction and prominent cortical and psychiatric signs presenting as a subacute fulminant or chronic progressive clinical course. Cigarette smokers may be overrepresented in this phenotype.
authors.affiliation: Department of Neurology, Mayo Clinic College of Medicine, 200 First St SW, Rochester, MN 55905, USA.
authors.forename: Nathan P
authors.initials: NP
authors.lastname: Staff
authors.forename: Claudia F
authors.initials: CF
authors.lastname: Lucchinetti
authors.forename: B Mark
authors.initials: BM
authors.lastname: Keegan
mesh_terms: D000208:Acute Disease / Q000453:epidemiology; D000328:Adult; D017668:Age of Onset; D001284:Atrophy / Q000453:epidemiology / Q000473:pathology / Q000523:psychology; D001921:Brain / Q000276:immunology / Q000473:pathology* / Q000503:physiopathology; D002531:Cerebellum / Q000276:immunology / Q000473:pathology / Q000503:physiopathology; D002540:Cerebral Cortex / Q000276:immunology / Q000473:pathology / Q000503:physiopathology; D003072:Cognition Disorders / Q000453:epidemiology* / Q000473:pathology* / Q000503:physiopathology; D015897:Comorbidity; D018450:Disease Progression; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009103:Multiple Sclerosis / Q000453:epidemiology* / Q000473:pathology* / Q000523:psychology; D010641:Phenotype; D012907:Smoking / Q000453:epidemiology; D013116:Spinal Cord / Q000276:immunology / Q000473:pathology / Q000503:physiopathology; D013997:Time Factors