Case study 70 - Prion disease AKA mad cow disease or Creutzfeldt-Jakob disease (CJD) Creutzfeldt-Jakob disease (CJD) is a transmissible spongiform encephalopathy that results in rapidly progressive dementia and death usually within a year from onset. The vast majority are sporadic, but familial and acquired forms are occasionally encountered. Prion diseases occur when normal prion protein, found on the surface of many cells, becomes abnormal and clump in the brain, causing brain damage. This abn