The 14-3-3 protein test has been shown to support the clinical diagnosis of sporadic Creutzfeldt-Jakob disease (CJD) when associated with an adequate clinical context, and a high differential potential for the diagnosis of sporadic CJD has been attributed to other cerebrospinal fluid (CSF) proteins such as tau protein, S100b and neuron specific enolase (NSE). So far there has been only limited information available about biochemical markers in genetic transmissible spongiform encephalopathies (gTSE), although they represent 10–15% of human TSEs. In this study, we analyzed CSF of 174 patients with gTSEs for 14-3-3 (n = 166), tau protein (n = 78), S100b (n = 46) and NSE (n = 50). Levels of brain-derived proteins in CSF varied in different forms of gTSE. Biomarkers were found positive in the majority of gCJD (81%) and insert gTSE (69%), while they were negative in most cases of fatal familial insomnia (13%) and Gerstmann-Sträussler-Scheinker syndrome (10%). Disease duration and codon 129 genotype influence the findings in a different way than in sporadic CJD.

Slovakia is characterised by an unusually high number of patients affected by genetic Creutzfeldt-Jakob disease (CJD) with E200K mutation at the PRNP gene. Penetrance of the mutation is incomplete (59%). Therefore, for the onset of the clinical manifestation, an influence of other endo-or exogenous factors could not be excluded. Experimental data suggest that copper and manganese levels may play an important role in the pathogenesis of prion diseases. The highest number of Slovak genetic CJD patients originates from Orava-the northern region of central Slovakia. Manganese is a dominant pollutant in Orava. The objective of this study was to clarify a possible exogenous influence of environmental Mn/Cu imbalance on the CJD clustering. Mn and Cu levels were analysed in the brain tissue of genetic CJD cases (from Orava and from control regions of Slovakia), as well as of sporadic CJD patients and controls. Analyses demonstrate i) significantly higher Mn level in focally accumulated, "clustering" genetic CJD cases in comparison to all other groups, ii) Cu status differences between compared groups were without statistical significance; decreased concentrations were found in genetic cases from extrafocal genetic CJD areas, iii) Mn/Cu ratios were increased in all CJD groups in comparison to controls. Metal ratios in clustering gCJD cases were significantly higher in comparison to sporadic cases and also to controls, but not to the extrafocal genetic CJD subgroup. These results indicate that more important than increasing Mn level in pathogenesis of CJD appears to be the role of the Mn/Cu imbalance in the CNS. The imbalance observed in the cluster of genetic CJD cases is probably a result of both: the excessive environmental Mn level and the disturbance of Mn/Cu ratios in the Orava region. Presented findings indicate an environmental Mn/Cu imbalance as a possible exogenous CJD risk co-factor which may, in coincidence with endogenous (genetic) CJD risk, contribute to the focal accumulation (cluster) of genetic CJD in Slovakia.

Creutzfeldt-Jakob disease is a rare, but rapidly progressive, up to now untreatable and fatal neurodegenerative disorder. Clinical diagnosis of Creutzfeldt-Jakob disease (CJD) is difficult; however, it can be facilitated by suitable biomarkers. Aim of the present study is to compare levels of cerebrospinal fluid biomarkers (total tau protein, phosphorylated-tau protein, protein 14-3-3 and amyloid beta) in Slovak population of CJD suspect cases, retrospectively in over a 10-year period. One thousand three hundred sixty-four CSF samples from patients with suspect CJD, forming a homogenous group in terms of geographical as well as of equal transport conditions, storage and laboratory processing, were analysed. Definite diagnosis of Creutzfeldt-Jakob disease was confirmed in 101 patients with genetic form, and 60 patients with its sporadic form of the disease. Specificity of protein 14-3-3 and total tau in both forms CJD was similar (87 % for P14-3-3/85 % for total tau), sensitivity to P 14-3-3 and total tau was higher in sporadic Creutzfeldt-Jakob disease (sCJD) (90/95 %) than in genetic Creutzfeldt-Jakob disease (gCJD) (89/74 %). As expected, the total tau levels were significantly higher in CJD patients than in controls, but there was also significant difference between gCJD and sCJD (levels in gCJD were lower; p = 0.003). There was no significant difference in p-tau and Aβ 1-42 levels neither between both CJD forms nor between CJD patients and control group.

Creutzfeldt-Jakob disease (CJD) is an untreatable rare human prion disease characterized by rapidly progressive dementia along with various neurological features, including myoclonus and sometimes other movement disorders. The clinical course is typically insidious and rapid, leading to an early death. In general, the most common form is sporadic CJD; however, Slovakia is typical for a high percentage of genetic cases. We present an unusual case report of a 65-year-old man with a sudden, stroke-like onset of motor aphasia with right-sided levodopa unresponsive parkinsonism, alien hand, and other characteristic features of corticobasal syndrome (CBS), with rapid deterioration and death on the 32nd day of the disease. Various neurodegenerative disorders are manifested with CBS as a clinical phenotype, including corticobasal degeneration (CBD), progressive supranuclear palsy, Alzheimer's disease, and CJD. In our patient, mutation E200K and M129M polymorphism of the PRNP gene and typical immunohistochemical findings pointed to a diagnosis of CJD. The patient's mother died of CJD many years ago. Several CBS-CJD cases were described, but the atypical stroke-like onset of CBS-CJD, an extremely rare presentation of CJD, makes our case unique worldwide.

An E200K mutation, which confers a risk of developing genetic CJD, was detected in corneal donors and in the general population. The majority of subjects were codon 129 methionine homozygous that increases susceptibility to CJD. Genetic testing of corneal donors in Slovakia is a useful and effective preventive measure against iatrogenic CJD through human corneal transplantation in the investigated population.