Role of the biomarkers for the diagnosis of Creutzfeldt-Jakob disease

Objective: Sporadic Creutzfeldt-Jakob disease (CJD) is a human prion disease, rapidly progressive and fatal, characterized by spongiform encephalopathy. The characteristic triad of signs - rapidly progressive dementia, myoclonus and periodic sharp wave complexes (PSWC) on electroencephalography (EEG) - usually appear in the late stages of the disease. The clinical diagnosis of CJD ante-mortem involves the exclusion of the rapidly progressive non-prionic dementias, the definitive diagnosis requiring brain tissue confirmation. Authors evaluated the methods of clinical diagnosis for sporadic CJD. Methods: This study retrospectively reviewed the medical records of patients diagnosed with probable sporadic CJD, based on brain magnetic resonance imaging (MRI), EEG, cerebrospinal fluid (CSF) analysis and extensive laboratory work-up. Results: Four patients with a mean age of 67 years were included in our study. The mean duration from diagnosis until death was of 3.2 weeks. The clinical features of the disease at onset were atypical. In the final stage of the disease, all patients presented rapidly progressive dementia and myoclonus. High levels of 14-3-3 protein and tau protein and normal levels of amyloid β1-42 were found at CSF analysis, in all patients. PSWC on EEG were present in 3 out of 4 patients at different moments of the disease. MRI showed hyperintense lesions in brain cortex, caudate nucleus, and putamen on T2, FLAIR, and DWI. Conclusion: CJD may present various clinical features and, since brain biopsy is usually difficult to perform, a combination of biomarkers is useful in order to establish the diagnosis in the early phase of the disease.