Health professions and risk of sporadic Creutzfeldt-Jakob disease, 1965 to 2010.

In 2009, a pathologist with sporadic Creutzfeldt-Jakob Disease (sCJD) was reported to the Spanish registry. This case prompted a request for information on health-related occupation in sCJD cases from countries participating in the European Creutzfeldt Jakob Disease Surveillance network (EuroCJD). Responses from registries in 21 countries revealed that of 8,321 registered cases, 65 physicians or dentists, two of whom were pathologists, and another 137 healthcare workers had been identified with sCJD. Five countries reported 15 physicians and 68 other health professionals among 2,968 controls or non-cases, suggesting no relative excess of sCJD among healthcare professionals. A literature review revealed: (i) 12 case or small case-series reports of 66 health professionals with sCJD, and (ii) five analytical studies on health-related occupation and sCJD, where statistically significant findings were solely observed for persons working at physicians' offices (odds ratio: 4.6 (95 CI: 1.2-17.6)). We conclude that a wide spectrum of medical specialities and health professions are represented in sCJD cases and that the data analysed do not support any overall increased occupational risk for health professionals. Nevertheless, there may be a specific risk in some professions associated with direct contact with high human-infectivity tissue.

Updated clinical diagnostic criteria for sporadic Creutzfeldt-Jakob disease.

Several molecular subtypes of sporadic Creutzfeldt-Jakob disease have been identified and electroencephalogram and cerebrospinal fluid biomarkers have been reported to support clinical diagnosis but with variable utility according to subtype. In recent years, a series of publications have demonstrated a potentially important role for magnetic resonance imaging in the pre-mortem diagnosis of sporadic Creutzfeldt-Jakob disease. Magnetic resonance imaging signal alterations correlate with distinct sporadic Creutzfeldt-Jakob disease molecular subtypes and thus might contribute to the earlier identification of the whole spectrum of sporadic Creutzfeldt-Jakob disease cases. This multi-centre international study aimed to provide a rationale for the amendment of the clinical diagnostic criteria for sporadic Creutzfeldt-Jakob disease. Patients with sporadic Creutzfeldt-Jakob disease and fluid attenuated inversion recovery or diffusion-weight imaging were recruited from 12 countries. Patients referred as 'suspected sporadic Creutzfeldt-Jakob disease' but with an alternative diagnosis after thorough follow up, were analysed as controls. All magnetic resonance imaging scans were assessed for signal changes according to a standard protocol encompassing seven cortical regions, basal ganglia, thalamus and cerebellum. Magnetic resonance imaging scans were evaluated in 436 sporadic Creutzfeldt-Jakob disease patients and 141 controls. The pattern of high signal intensity with the best sensitivity and specificity in the differential diagnosis of sporadic Creutzfeldt-Jakob disease was identified. The optimum diagnostic accuracy in the differential diagnosis of rapid progressive dementia was obtained when either at least two cortical regions (temporal, parietal or occipital) or both caudate nucleus and putamen displayed a high signal in fluid attenuated inversion recovery or diffusion-weight imaging magnetic resonance imaging. Based on our analyses, magnetic resonance imaging was positive in 83% of cases. In all definite cases, the amended criteria would cover the vast majority of suspected cases, being positive in 98%. Cerebral cortical signal increase and high signal in caudate nucleus and putamen on fluid attenuated inversion recovery or diffusion-weight imaging magnetic resonance imaging are useful in the diagnosis of sporadic Creutzfeldt-Jakob disease. We propose an amendment to the clinical diagnostic criteria for sporadic Creutzfeldt-Jakob disease to include findings from magnetic resonance imaging scans.

A novel PSEN2 mutation associated with a peculiar phenotype.

BACKGROUND: Mutations of presenilin 2 gene are a rare cause of familial Alzheimer disease (AD). We describe an Italian family with hereditary dementia associated with a novel mutation in the presenilin 2 gene. METHODS: Clinical investigations of the diseased subjects; interviews with relatives; studies of medical records; pedigree analysis; and neuroradiologic, neuropathologic, and molecular genetic studies were carried out in the pedigree. RESULTS: Genetic analysis showed a novel PSEN2 A85V mutation present in the proband and in all analyzed affected members, in a subject presenting with an amnesic mild cognitive impairment, and in a young, still asymptomatic subject. The proband showed a clinical phenotype indicative of Lewy body dementia and the neuropathologic examination demonstrated the presence of unusually abundant and widespread cortical Lewy bodies in addition to the hallmark lesions of AD. Other affected members exhibited a clinical phenotype typical of AD. CONCLUSIONS: Our findings add complexity to the spectrum of atypical phenotypes associated with presenilin mutations and should then be taken into account when considering the nosography of neurodegenerative diseases. They also support previous data that specific mutations of genes associated with familial Alzheimer disease may influence the presence and extent of Lewy bodies.

Codon 129 polymorphism of prion protein gene in sporadic Alzheimer's disease.

Codon 129 polymorphism of the prion protein gene represents a major genetic risk factor for Creutzfeldt-Jakob disease (CJD). Both CJD and Alzheimer's disease (AD) are brain amyloidoses and it would be possible that codon 129 polymorphism plays a role in the susceptibility to AD. In order to investigate this polymorphism in AD the distribution of polymorphic codon 129 of the PRNP gene in 194 probable AD and 124 controls selected in Italy and 109 neuropathologically verified AD and 58 matched controls recruited in the USA was studied. No significant association was found for the PRNP polymorphism in AD compared to controls either in Probable or in Definite AD series even after stratification for APOE polymorphism. This study does not support a role of PRNP polymorphism as a susceptibility factor for AD.

Quantitative profiling of the pathological prion protein allotypes in bank voles by liquid chromatography-mass spectrometry.

The conversion of the cellular prion protein (PrP(C)) into a misfolded isoform (PrP(TSE)) that accumulates in the brain of affected individuals is the key feature of transmissible spongiform encephalopaties (TSEs). Susceptibility to TSEs is influenced by polymorphisms of the prion gene suggesting that the presence of certain amino acid residues may facilitate the pathological conversion. In this work, we describe a quantitative, fast and reliable HPLC-MS method that allowed to demonstrate that in the brain of 109(Met/Ile) heterozygous bank voles infected with the mouse adapted scrapie strain 139A, there are comparable amounts of PrP(TSE) with methionine or isoleucine in position 109, suggesting that in this TSE model the two allotypes have similar rates of accumulation. This method can be easily adapted for the quantitative determination of PrP allotypes in the brain of other natural or experimental TSE models.

Determinants of diagnostic investigation sensitivities across the clinical spectrum of sporadic Creutzfeldt-Jakob disease.

To validate the provisional findings of a number of smaller studies and explore additional determinants of characteristic diagnostic investigation results across the entire clinical spectrum of sporadic Creutzfeldt-Jakob disease (CJD), an international collaborative study was undertaken comprising 2451 pathologically confirmed (definite) patients. We assessed the influence of age at disease onset, illness duration, prion protein gene (PRNP) codon 129 polymorphism (either methionine or valine) and molecular sub-type on the diagnostic sensitivity of EEG, cerebral MRI and the CSF 14-3-3 immunoassay. For EEG and CSF 14-3-3 protein detection, we also assessed the influence of the time point in a patient's illness at which the investigation was performed on the likelihood of a typical or positive result. Analysis included a large subset of patients (n = 743) in whom molecular sub-typing had been performed using a combination of the PRNP codon 129 polymorphism and the form of protease resistant prion protein [type 1 or 2 according to Parchi et al. (Parchi P, Giese A, Capellari S, Brown P, Schulz-Schaeffer W, Windl O, Zerr I, Budka H, Kopp N, Piccardo P, Poser S, Rojiani A, Streichemberger N, Julien J, Vital C, Ghetti B, Gambetti P, Kretzschmar H. Classification of sporadic Creutzfeldt-Jakob disease based on molecular and phenotypic analysis of 300 subjects. Ann Neurol 1999; 46: 224-233.)] present in the brain. Findings for the whole group paralleled the subset with molecular sub-typing data available, showing that age at disease onset and disease duration were independent determinants of typical changes on EEG, while illness duration significantly influenced positive CSF 14-3-3 protein detection; changes on brain MRI were not influenced by either of these clinical parameters, but overall, imaging data were less complete and consequently conclusions are more tentative. In addition to age at disease onset and illness duration, molecular sub-type was re-affirmed as an important independent determinant of investigation results. In multivariate analyses that included molecular sub-type, time point of the investigation during a patient's illness was found not to influence the occurrence of a typical or positive EEG or CSF 14-3-3 protein result. A typical EEG was most often seen in MM1 patients and was significantly less likely in the MV1, MV2 and VV2 sub-types, whereas VV2 patients had an increased likelihood of a typical brain MRI. Overall, the CSF 14-3-3 immunoassay was the most frequently positive investigation (88.1%) but performed significantly less well in the very uncommon MV2 and MM2 sub-types. Our findings confirm a number of determinants of principal investigation results in sporadic CJD and underscore the importance of recognizing these pre-test limitations before accepting the diagnosis excluded or confirmed. Combinations of investigations offer the best chance of detection, especially for the less common molecular sub-types such as MV2 and MM2.

Identification of the pathological prion protein allotypes in scrapie-infected heterozygous bank voles (Clethrionomys glareolus) by high-performance liquid chromatography-mass spectrometry.

Cerebral formation of the pathological isoform of the prion protein (PrP) is a crucial molecular event in prion diseases. The bank vole (Clethrionomys glareolus) is a rodent species highly susceptible to natural scrapie. The PrP gene of bank vole is polymorphic (Met/Ile) at codon 109. Here we show that homozygous 109Met/Met voles have incubation times shorter than heterozygous 109Met/Ile voles after experimental challenge with three different scrapie isolates. An HPLC-MS/MS method was optimized and applied to investigate whether in heterozygous animals both PrP allotypes are able to undergo pathological conversion. The results demonstrate that both allotypes of the prion protein participate to pathological deposition.

Mortality from Creutzfeldt-Jakob disease and related disorders in Europe, Australia, and Canada.

BACKGROUND: An international study of the epidemiologic characteristics of Creutzfeldt-Jakob disease (CJD) was established in 1993 and included national registries in France, Germany, Italy, the Netherlands, Slovakia, and the United Kingdom. In 1997, the study was extended to Australia, Austria, Canada, Spain, and Switzerland. METHODS: Data were pooled from all participating countries for the years 1993 to 2002 and included deaths from definite or probable CJD of all etiologic subtypes. RESULTS: Four thousand four hundred forty-one cases were available for analysis and included 3,720 cases of sporadic CJD, 455 genetic cases, 138 iatrogenic cases, and 128 variant cases. The overall annual mortality rate between 1999 and 2002 was 1.67 per million for all cases and 1.39 per million for sporadic CJD. Mortality rates were similar in all countries. There was heterogeneity in the distribution of cases by etiologic subtype with an excess of genetic cases in Italy and Slovakia, of iatrogenic cases in France and the UK, and of variant CJD in the UK. CONCLUSIONS: This study has established overall epidemiologic characteristics for Creutzfeldt-Jakob disease (CJD) of all types in a multinational population-based study. Intercountry comparisons did not suggest any relative change in the characteristics of sporadic CJD in the United Kingdom, and the evidence in this study does not suggest the occurrence of a novel form of human bovine spongiform encephalopathy infection other than variant CJD. However, this remains a possibility, and countries currently unaffected by variant CJD may yet have cases.

High incidence of genetic human transmissible spongiform encephalopathies in Italy.

OBJECTIVE: To assess the incidence and mortality rates of genetic transmissible spongiform encephalopathy (TSE) diseases in Italy. METHODS: The authors have sequenced the prion protein gene (PRNP) in 643 patients referred to the Italian Registry of Creutzfeldt-Jakob disease (CJD) and related disorders between 1993 and 2002. Crude age- and sex-specific incidence and mortality rates were calculated. Differences in morbidity from genetic TSE diseases in the 20 Italian regions were assessed by the standardized morbidity ratio (SMR). RESULTS: A total of 130 cases were classified as genetic TSE diseases with a mean yearly incidence rate of 0.28 cases per million people. Genetic TSE diseases represent 17.7% of all TSE diseases, including sporadic, iatrogenic, and variant CJD. The most frequent mutation was the V210I (n = 54), and the second most common the E200K (n = 42). Mortality rates for genetic TSE diseases did not increase in any of the age groups under examination over the 10 years of surveillance. The analysis of regional distribution of genetic cases by place of birth revealed that in Campania and Calabria regions the number of genetic TSE cases was higher than in other regions. CONCLUSIONS: In Italy the incidence of genetic transmissible spongiform encephalopathy (TSE) diseases is the second highest among European countries. Genetic analysis is important for a correct classification of patients with TSE.

Creutzfeldt-Jakob disease associated with the R208H mutation in the prion protein gene.

The authors investigated a patient who died of apparent sporadic Creutzfeldt-Jakob disease (CJD) but carried a R208H substitution in the prion protein (PrP). The patient phenotype was indistinguishable from typical sporadic CJD (i.e., MM1 subtype). In addition, pathologic PrP, PrP(Sc), originated from both the normal and the mutated PRNP allele and had the same characteristics as PrP(Sc) type 1. The authors propose that the R208H mutation influences disease susceptibility without significantly affecting PrP(Sc) properties or disease phenotype.

Predictors of survival in sporadic Creutzfeldt-Jakob disease and other human transmissible spongiform encephalopathies.

A collaborative study of human transmissible spongiform encephalopathies has been carried out from 1993 to 2000 and includes data from 10 national registries, the majority in Western Europe. In this study, we present analyses of predictors of survival in sporadic (n = 2304), iatrogenic (n = 106) and variant Creutzfeldt-Jakob disease (n = 86) and in cases associated with mutations of the prion protein gene (n = 278), including Gerstmann-Sträussler-Scheinker syndrome (n = 24) and fatal familial insomnia (n = 41). Overall survival for each disease type was assessed by the Kaplan-Meier method and the multivariate analyses by the Cox proportional hazards model. In sporadic disease, longer survival was correlated with younger age at onset of illness, female gender, codon 129 heterozygosity, presence of CSF 14-3-3 protein and type 2a prion protein type. The ability to predict survival based on patient covariates is important for diagnosis and counselling, and the characterization of the survival distributions, in the absence of therapy, will be an important starting point for the assessment of potential therapeutic agents in the future.

Increased CSF levels of prostaglandin E(2) in variant Creutzfeldt-Jakob disease.

The concentration of the cyclooxygenase product prostaglandin E(2) was sixfold higher in CSF samples from 18 cases of variant Creutzfeldt-Jakob disease (CJD) than in a group of eight subjects with other noninflammatory neurologic diseases, and comparable to those found in a group of six patients affected by diseases with a known inflammatory component. This finding suggests that cyclooxygenase activity may have a role in variant CJD pathogenesis, as previously reported in sporadic CJD.

Mutation of the PRNP gene at codon 211 in familial Creutzfeldt-Jakob disease.

Creutzfeldt-Jakob disease (CJD) belongs to a group of chronic, progressive, neurodegenerative disorders that may be hereditary, infectious, or sporadic. Hereditary CJDs are associated with mutations in the PRNP gene on chromosome 20p12-pter. We report a family in which four patients developed classical clinical signs of CJD, including severe cognitive decline, cerebellar signs, myoclonic jerks, and synchronic periodic discharges on electroencephalogram. The E211Q mutation has been identified in family members, but not in 97 sporadic CJD patients referred to the Italian registry of CJD nor in 205 healthy normal subjects, suggesting a pathogenic role for this mutation.

Iatrogenic Creutzfeldt-Jakob disease at the millennium.

The causes and geographic distribution of 267 cases of iatrogenic Creutzfeldt-Jakob disease (CJD) are here updated at the millennium. Small numbers of still-occurring cases result from disease onsets after longer and longer incubation periods following infection by cadaveric human growth hormone or dura mater grafts manufactured and distributed before the mid-1980s. The proportion of recipients acquiring CJD from growth hormone varies from 0.3 to 4.4% in different countries, and acquisition from dura mater varies between 0.02 and 0.05% in Japan (where most cases occurred). Incubation periods can extend up to 30 years, and cerebellar onsets predominate in both hormone and graft recipients (in whom the site of graft placement had no effect on the clinical presentation). Homozygosity at codon 129 of the PRNP gene is over-represented in both forms of disease; it has no effect on the incubation period of graft recipients, but may promote shorter incubation periods in hormone cases. Knowledge about potential high-risk sources of contamination gained during the last quarter century, and the implementation of methods to circumvent them, should minimize the potential for iatrogenic contributions to the current spectrum of CJD.

Increased brain synthesis of prostaglandin E2 and F2-isoprostane in human and experimental transmissible spongiform encephalopathies.

The levels of 2 arachidonic acid metabolites formed either by enzymatic activity of cyclooxygenase, i.e. prostaglandin E2 (PGE2), or by free radical-catalyzed peroxidation, i.e. F2-isoprostane 8-epi-prostaglandin F2alpha (8-epi-PGF2alpha), were measured in the CSF of subjects with sporadic and familial Creutzfeldt-Jakob disease (CJD) and in brain homogenates of scrapie-infected mice. The CSF levels of both metabolites were increased in sporadic CJD (n = 52) and familial CJD (n = 10) patients when compared with a group of patients with noninflammatory disorders. Similarly, PGE2 and 8-epi-PGF2alpha levels were higher in brain homogenates obtained from C57BL/6J mice infected with the ME7 scrapie strain than in brain homogenates from control animals. As PGE2 is 1 of the most abundant prostaglandins released during inflammation and 8-epi-PGF2alpha is a quantitative marker of lipid peroxidation, our results provide in vivo biochemical evidence for the occurrence of inflammation and oxidative stress in human and experimental transmissible spongiform encephalopathies (TSEs), a concept so far based mainly on histopathological and in vitro evidence. Interestingly, in sporadic CJD patients, high CSF levels of PGE2, but not 8-epi-PGF2alpha, correlated with short survival time, suggesting that the inflammatory response correlates with the clinical duration of disease.

Analysis of EEG and CSF 14-3-3 proteins as aids to the diagnosis of Creutzfeldt-Jakob disease.

OBJECTIVE: To improve diagnostic criteria for sporadic Creutzfeldt-Jakob disease (CJD). METHODS: Pooled data on initial and final diagnostic classification of suspected CJD patients were accumulated, including results of investigations derived from a coordinated multinational study of CJD. Prospective analysis for a comparison of clinical and neuropathologic diagnoses and evaluation of the sensitivity and specificity of EEG and 14-3-3 CSF immunoassay were conducted. RESULTS: Data on 1,003 patients with suspected CJD were collected using a standard questionnaire. After follow-up was carried out, complete clinical data and neuropathologic diagnoses were available in 805 cases. In these patients, the sensitivity of the detection of periodic sharp wave complexes in the EEG was 66%, with a specificity of 74%. The detection of 14-3-3 proteins in the CSF correlated with the clinical diagnosis in 94% (sensitivity). The specificity (84%) was higher than that of EEG. A combination of both investigations further increased the sensitivity but decreased the specificity. CONCLUSIONS: Incorporation of CSF 14-3-3 analysis in the diagnostic criteria for CJD significantly increases the sensitivity of case definition. Amended diagnostic criteria for CJD are proposed.

A rapid and efficient method for the detection of point mutations of the human prion protein gene (PRNP) by direct sequencing.

Creutzfeldt-Jakob disease (CJD) and related disorders occur in sporadic, acquired and inherited forms. In sporadic, iatrogenic and new variant CJD the polymorphic codon 129 of the prion protein gene (PRNP) plays an important role for the susceptibility to the disease and for the clinical and neuropathological manifestations. All the inherited forms of CJD and related disorders are linked to point or insert mutations of PRNP. The analysis of PRNP is therefore important for a correct classification of these disorders and for the identification of novel mutations. The aim of the present study is to describe a fast and easy to perform method for the direct sequencing of the PCR amplified PRNP open reading frame, by using M13 tailed primers which allow a direct and rapid method of sequencing. The goodness of this method is demonstrated in the analysis of three sporadic CJD patients with different genotypes at codon 129 and three inherited cases bearing different point mutations of PRNP: the Pro102Leu mutation linked to Gerstmann-Sträussler-Scheinker-syndrome, the Val210Ile mutation and a novel mutation at codon 211 (Gln211Glu) both associated to familial CJD.