Introduction
Prion diseases are a group of rare neurodegenerative diseases that are caused by infectious abnormally structured and shaped proteins - prions - which impose their structure onto nearby normal prion proteins, thereby propagating and causing progressive cell damage and death [1]. Creutzfeldt – Jakob disease (CJD) is the most common human prion disease and has a prevalence of 1 new case per 1 million individuals each year worldwide and usually presents in the 7th decade of life [2]. Sporadic CJD (sCJD) accounts for up to 85-95% of CJD cases, while other genetic and acquired forms are far less common, accounting for 5-15% and less than 1% of cases, respectively [3].
CJD is a clinically heterogeneous disease but typically presents with rapid cognitive and neuropsychiatric deterioration. The most common clinical presentation is rapid cognitive decline progressing to dementia; other manifestations include behavioral abnormalities, myoclonus, pyramidal/extrapyramidal signs, cerebellar symptoms and higher cortical dysfunction (i.e., aphasia, apraxia, acalculia, agraphia, neglect), which are seen in about half of all reported cases [4; 5; 6]. Clinical picture, in combination with cerebrospinal fluid (CSF), electroencephalography (EEG), and brain magnetic resonance imaging (MRI) studies form the basis of in vivo diagnosis of CJD; histopathological confirmation, however, still remains the gold standard for diagnosing definite CJD (Table 1). MRI is a very valuable tool in detecting signal abnormalities suggestive of CJD in an appropriate clinical context, approaching a sensitivity of 91% and a specificity of 95% [7].
Unfortunately, CJD is incurable and universally fatal, usually progressing rapidly over 6 to 12 months.