Creutzfeldt - Jakob disease (CJD) is a rare neurodegenerative disease caused by prions, characterized by a progressive dementia with rapid onset, psychiatric and neurologic symptoms (myoclonus, cerebellar, pyramidal, extrapyramidal and visual signs), with an invariable course to exitus. There are three general forms: sporadic or spontaneous, genetic or familial, and acquired form, including a variant form of CJD. The diagnosis can be confirmed only by histological examination of brain tissue, showing non-inflammatory spongiform changes and neuronal loss. We present the case of a 64 years old male who was admitted in our department for a rapidly progressive cognitive decline, hallucinations and myoclonus. Autopsy brain histology confirmed the diagnosis showing incipient spongiform vacuolization and astrogliosis. This paper illustrates a very rapid course of a sporadic CJD with discussion upon literature regarding the laboratory and pathology biomarkers of diagnosis.