title: The alien limb phenomenon and Creutzfeldt-Jakob disease.
abstract: BACKGROUND
  Alien limb phenomenon (ALP) has been rarely reported as a presenting feature of Creutzfeldt-Jakob disease (CJD), though neurologists may not recognize it as a prompt to search for CJD.
  
  
  OBJECTIVE
  This report demonstrates the clinical features of patients with ALP and CJD.
  
  
  METHODS
  All patients with the ALP between 1/1/1996 - 7/28/2011 were identified by the Mayo Clinic Medical Record Linkage system and cross-referenced with a diagnosis of CJD in that same time span. This yielded 13 patients, including six women.
  
  
  RESULTS
  The median age at onset of CJD symptoms was 69 years. Two patients were classified as possible CJD, five as probable CJD, and six as definite CJD based on research diagnostic criteria for CJD. The median time to onset of ALP symptoms was 0.5 weeks. The ALP afflicted the left side in nine patients. The median time to death from CJD symptom onset was 10.5 weeks. In four patients ALP was the initial and sole neurologic sign. In four others it was the initial manifestation coexisting with other deficits. ALP related symptoms initially prompted three other patients to seek medical evaluation. ALP was either initially or eventually accompanied by ipsilateral hemineglect, ideomotor apraxia and/or cortical sensory loss in nine patients. Imaging of the contralateral parietal lobe demonstrated cortical T2 hyperintensity and/or restricted diffusion in all eight patients who had abnormal MRI neuroimaging.
  
  
  CONCLUSIONS
  ALP should trigger suspicion of CJD. The neuroanatomic correlate of ALP in CJD appears to be the contralateral parietal lobe.
authors.affiliation: Department of Neurology, E8A, Mayo Clinic College of Medicine, 200 First Street SW, Rochester, MN 55901, USA. rubin.mark@mayo.edu
authors.forename: Mark
authors.initials: M
authors.lastname: Rubin
authors.forename: Jonathan
authors.initials: J
authors.lastname: Graff-Radford
authors.forename: Bradley
authors.initials: B
authors.lastname: Boeve
authors.forename: Keith A
authors.initials: KA
authors.lastname: Josephs
authors.forename: Allen J
authors.initials: AJ
authors.lastname: Aksamit
mesh_terms: D000328:Adult; D000368:Aged; D007562:Creutzfeldt-Jakob Syndrome / Q000175:diagnosis / Q000503:physiopathology*; D004569:Electroencephalography; D005260:Female; D006225:Hand / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009460:Neurologic Examination