39.: Rapidly progressive dementia and protein 14-3-3 in cerebrospinal fluid: Not always Creutzfeldt-Jakob disease

This study aimed to illustrate difficulties of accurately diagnosing a rapidly progressive dementia syndrome and the unspecific nature of presence of 14-3-3 protein in the cerebrospinal fluid. An 84-year-old gentleman was transferred from a private rehabilitation hospital after a surgical repair of neck of femur fracture in a state of persistent drowsiness intermixed with lucid intervals with visual hallucinations. Initial electroencephalogram showed triphasic delta waves that did not change with gradual escalation of antiepileptic medication. MRI and bloods were unremarkable. His cerebrospinal fluid revealed normal proteins and protein 14-3-3, done through the Australian Creutzfeldt-Jakob Disease Registry in Melbourne, was positive. He was given a presumptive diagnosis of Creutzfeldt-Jakob disease and his family was counselled appropriately. He passed away in a nursing home 2 months later. Subsequent brain biopsy revealed no spongiform changes but intracytoplasmic Lewy bodies in neurons of frontal, temporal and parietal cortices. Despite widely held notion, positive 14-3-3 test is not diagnostic of Creutzfeldt-Jakob disease in a patient with rapidly progressive dementia.