A retrospective study of Creutzfeldt-Jakob disease in England and Wales 1970-1979. II: Epidemiology

Creutzfeldt-Jakob Disease and Fatal Familial Insomnia: Demographics and In-Hospital Mortality in Spain

Background: Creutzfeldt-Jakob disease (CJD) and fatal familial insomnia (FFI) are prion diseases characterized by severe neurodegenerative conditions and a short duration of illness. Methods: This study explores the characteristics of hospitalizations for CJD and FFI in Spain from 2016 to 2022 using the Spanish National Hospital Discharge Database (SNHDD). Results: We identified a total of 1063 hospital discharges, including 1020 for CJD and 43 for FFI. Notably, the number of hospitalized patients with FFI showed a significant peak in 2017. The average length of hospital stay (LOHS) was 13 days for CJD and 6 days for FFI, with in-hospital mortality rates (IHM) of 36.37% for CJD and 32.56% for FFI. Among CJD patients, the average LOHS was 14 days, with a significantly longer duration for those who experienced IHM. Conclusions: The presence of sepsis or pneumonia and older age were associated with a higher IHM rate among CJD patients. The total estimated cost for managing CJD and FFI patients over the study period was EUR 6,346,868. This study offers new insights into the epidemiology and healthcare resource utilization of CJD and FFI patients, which may inform future research directions and public health strategies.

Case report: Creutzfeldt-Jakob disease presenting with anxiety symptoms in a COVID-19 post-infection patient

Creutzfeldt-Jakob Disease (CJD) is a rare, rapidly progressive, and fatal neurodegenerative disorder. We describe a man whose initial manifestations of CJD occurred shortly after contracting Coronavirus disease 2019 (COVID-19). He first developed anxiety and short-term memory loss a few weeks after a mild COVID-19 infection. He subsequently developed parkinsonism, eventually progressed to akinetic mutism, and passed away 5 months after symptom onset. This case highlights a potential temporal relationship between COVID-19 infection and the onset of neurodegenerative symptoms. Microglia and astrocytes in the central nervous system (CNS) and 'S1' spike proteins on SARS-CoV-2 are potential mediators in neuroinflammation and neurodegeneration.

Validation of Revised International Creutzfeldt-Jakob Disease Surveillance Network Diagnostic Criteria for Sporadic Creutzfeldt-Jakob Disease

IMPORTANCE

Sporadic Creutzfeldt-Jakob disease (sCJD) is a rapidly lethal disease. Rapid, accurate diagnosis is imperative for epidemiological surveillance and public health activities to exclude treatable differentials and facilitate supportive care. In 2017, the International CJD Surveillance Network diagnostic criteria were revised to incorporate cortical ribboning on magnetic resonance imaging and the real-time quaking-induced conversion (RT-QuIC) assay, developments that require multicenter evaluation.

OBJECTIVE

To evaluate the accuracy of revised diagnostic criteria through the retrospective diagnosis of autopsy-confirmed cases (referred to as in-life diagnosis).

DESIGN, SETTING, AND PARTICIPANTS

This diagnostic study used a 3-year clinicopathological series using all cases of autopsy-confirmed sCJD and a noncase group with alternative neuropathological diagnoses from national surveillance centers in the United Kingdom, France, Germany, and Italy. Data were collected from January 2017 to December 2019 and analyzed from January 2020 to November 2021.

MAIN OUTCOMES AND MEASURES

Sensitivity and specificity of revised diagnostic criteria and diagnostic investigations. Secondary analyses assessing sCJD subgroups by genotype, pathological classification, disease duration, and age.

RESULTS

A total of 501 sCJD cases and 146 noncases were included. Noncase diagnoses included neurodegenerative diseases, autoimmune encephalitis, and cerebral insults such as anoxia. Participants in the sCJD cases cohort were younger (mean [SD] age, 68.8 [9.8] years vs 72.8 [10.9] years; P < .001) and had longer median (IQR) disease duration (118 [74.8-222.3] days vs 85 [51.5-205.5] days; P = .002); sex ratios were equivalent (253 [50.5%] male cases vs 74 [50.7%] male noncases). Sensitivity of revised criteria in in-life diagnosis (450 of 488 [92.2%] diagnoses; 95% CI, 89.5%-94.4%) was increased compared with prior criteria (378 of 488 [77.5%] diagnoses; 95% CI, 73.5%-81.1%; P < .001), while specificity (101 of 125 [80.8%] diagnoses; 95% CI, 72.8%-87.3%) was unchanged (102 of 125 [81.6%] diagnoses; 95% CI, 73.7%-88.0%; P > .99). Among 223 cases and 52 noncases with the full panel of investigations performed, sensitivity of revised criteria (97.8%; 95% CI, 94.9%-99.3%) was increased compared with prior criteria (76.2%; 95% CI, 70.1%-81.7%; P < .001) while specificity was unchanged (67.3%; 95% CI, 52.9%-79.7% vs 69.2%; 95% CI, 54.9%-81.3%; P > .99). In 455 cases and 111 noncases, cortical ribboning was 67.9% sensitive (95% CI, 63.4%-72.2%) and 86.5% specific (95% CI, 78.7%-92.2%). In 274 cases and 77 noncases, RT-QuIC was 91.6% sensitive (95% CI, 87.7%-94.6%) and 100% specific (95% CI, 96.2%-100%). Investigation sensitivity varied with genetic and pathological features, disease duration, and age.

CONCLUSIONS AND RELEVANCE

This diagnostic study demonstrated significantly improved sensitivity of revised sCJD diagnostic criteria with unaltered specificity. The revision has enhanced diagnostic accuracy for clinical care and surveillance.

The importance of ongoing international surveillance for Creutzfeldt-Jakob disease

Creutzfeldt-Jakob disease (CJD) is a rapidly progressive, fatal and transmissible neurodegenerative disease associated with the accumulation of misfolded prion protein in the CNS. International CJD surveillance programmes have been active since the emergence, in the mid-1990s, of variant CJD (vCJD), a disease linked to bovine spongiform encephalopathy. Control measures have now successfully contained bovine spongiform encephalopathy and the incidence of vCJD has declined, leading to questions about the requirement for ongoing surveillance. However, several lines of evidence have raised concerns that further cases of vCJD could emerge as a result of prolonged incubation and/or secondary transmission. Emerging evidence from peripheral tissue distribution studies employing high-sensitivity assays suggests that all forms of human prion disease carry a theoretical risk of iatrogenic transmission. Finally, emerging diseases, such as chronic wasting disease and camel prion disease, pose further risks to public health. In this Review, we provide an up-to-date overview of the transmission of prion diseases in human populations and argue that CJD surveillance remains vital both from a public health perspective and to support essential research into disease pathophysiology, enhanced diagnostic tests and much-needed treatments.

Creutzfeldt-Jakob disease mortality in Canada, 1998 to 2013

BACKGROUND

Human prion diseases, known collectively as Creutzfeldt-Jakob disease (CJD), are fatal, infectious neurodegenerative disorders that occur in all human populations.

OBJECTIVE

To summarize national surveillance data for CJD in Canada between January 1, 1998, and December 31, 2013.

METHODS

Detailed investigations were conducted of individual suspected CJD cases, with collaboration between Canadian health professionals and investigators affiliated with a central CJD surveillance registry operated by the Public Health Agency of Canada. Data were collected on the clinical profile, family history, and results of paraclinical and laboratory investigations, including post-mortem neuropathological examination.

RESULTS

A total of 662 deaths from definite and probable CJD were identified in Canadian residents during the study period, comprising 613 cases of sporadic CJD (92.6%), 43 cases of genetic prion disease (6.5%), 4 cases of iatrogenic CJD (0.6%), and 2 cases of variant CJD disease (0.3%). The overall crude mortality rate for sporadic CJD was 1.18 per million per year [95% confidence interval (CI): 1.08,1.27]. Age-specific rates ranged from 0.05 [95% CI: 0.03,0.08] in persons under 50 years of age to 7.11 [95% CI: 6.20,8.11] in those aged 70 to 79. A significant net upward trend in age-adjusted rates was observed over the study period. Standardized mortality ratios, calculated for 10 individual Canadian provinces with reference to national average mortality rates, did not differ significantly from 1.0.

CONCLUSION

Creutzfeldt-Jakob disease remains rare in Canada, although mortality rates vary by two orders of magnitude between older and younger age groups. The upward trend in age-standardized sporadic CJD mortality rate over the study period can be better accounted for by gradually improving case ascertainment than by a real increase in incidence.

The different faces of Creutzfeldt-Jacob disease CJD in psychiatry

OBJECTIVE

Creutzfeldt-Jacob Disease (CJD) is a rapidly progressive spongiform disease of the central nervous system. Psychiatric symptoms, though considered rare, can be the presenting symptoms of CJD and impose diagnosis difficulties. We reviewed prospectively our database to identify the frequency of psychiatric symptoms as identifying symptoms among our community.

METHODS

We included all patients in Sheba Medical Center who were diagnosed with CJD between the years 2006 and 2012. Data were collected retrospectively.

RESULTS

Twenty-three patients with CJD were admitted to our hospital during this 6-year period. Among them, 10 (44%) were diagnosed first as "psychiatric patients" due to psychiatric presenting symptoms.

CONCLUSION

In our series, the frequency of misleading psychiatric symptom was 44%. Clinicians should therefore include CJD in their differential diagnoses of new onset dementia, particularly when associated psychosis and depression symptoms persist and worsen, despite standard psychiatric treatments.

Incidence of Creutzfeldt-Jakob disease in Taiwan: a prospective 10-year surveillance

This study was performed to estimate the incidence of Creutzfeldt-Jakob Disease (CJD) in Taiwan from 1998 to 2007. Suspected cases of CJD were reported to the Taiwan Creutzfeldt-Jakob Disease Surveillance Unit, a nationwide, hospital-based case report system initiated since 1996 to prospectively conduct a CJD epidemiological study. Consecutive patients who met the diagnostic criteria recommended by the World Health Organization were enrolled. The clinical information of each suspected case was collected and case ascertainment was performed by an expert committee. A total of 123 sporadic CJD were identified without any iatrogenic or new variant CJD cases. The overall annual incidence rate (95% CI) was 0.55 (0.46-0.65) cases per million person-year. There was no statistically significant difference between the calendar year of disease onset (P = 0.97). The incidence rates were not significantly different between women and men (P = 0.63). Age was the main factor for the risk of CJD (P < 0.0001). Age-specific incidence rate increased after the age of 40 years with the peak being in the 70-79 years age group. Our data showed low annual incidence rate and high frequency of methionine homozygous prion protein genotype of sCJD in Taiwan. This report provided important epidemiological data on ethnic Chinese.

Metal microcrystal pollutants: the heat resistant, transmissible nucleating agents that initiate the pathogenesis of TSEs?

This paper exposes the flaws in the conventional consensus on the origins of transmissible spongiform encephalopathies (TSEs) which decrees that the protein-only misfolded 'prion' represents the primary aetiological transmissible agent, and then reviews/presents the emerging data which indicates that environmental exposure to metal microcrystal pollutants (sourced from munitions, etc.) represents the heat resistant, transmissible nucleating agents which seed the metal-prion protein (PrP)-ferritin fibril crystals that cause TSE. Fresh analytical data is presented on the levels of metals in ecosystems which support populations affected by clusters of variant Creutzfeldt-Jacob disease (vCJD), sporadic/familial CJD, and the scrapie types of TSE that have emerged in the UK, Sicily, Sardinia, Calabria and Japan. This data further substantiates the abnormal geochemical template (e.g., elevated strontium (Sr), barium (Ba) and silver (Ag)) which was observed as a common hallmark of the TSE cluster ecosystems across North America, thereby supporting the hypothesis that these microcrystals serve as the piezoelectrion nucleators which seed the growth/multireplication of the aberrant metal-PrP-ferritin fibril features which characterise the neuropathology of the TSE diseased brain. A secondary pathogenic mechanism entails the inactivation of the sulphated proteoglycans which normally regulate the mineralisation process. This can be induced by a rogue metal mediated chelation of free sulphur, or by contamination with organo-sulphur pollutants that substitute at natural sulphur bonds, or via a mutation to the S-proteoglycan cell line; thereby enabling the aberrant overgrowth of rogue fibril crystal formations that possess a piezoelectric capacity which compromises the ability of the contaminated individual to process incoming acoustic/tactile pressure waves in the normal way. The crystals transduce incoming sonic energy into electrical energy, which, in turn, generates magnetic fields on the crystal surfaces that initiate chain reactions of free radical mediated spongiform neurodegeneration. Metal microcrystal nucleating agents provide a group of plausible aetiological candidates that explain the unique properties of the TSE causal agent - such as heat resistance, transmissibility, etc. - which the protein-only prion model fails to fulfill. This paper also discusses the possible nutritional measures that could best be adopted by populations living in high risk TSE ecosystems; as a means of preventing the successful implantation of these rogue microcrystals and their consequent hypermineralisation of the soft tissues within the CNS.

Creutzfeldt-Jakob disease in Slovenia from 1985 to 2003

AIM

The epidemic of bovine spongiform encephalopathy and subsequent emergence of a new variant of Creutzfeldt-Jakob disease have raised great public concern, initiating improved and prospective surveillance of human prion diseases in Europe and all over the world. This report briefly presents the epidemiology, clinical data, neuropathology, immunohistochemistry, biochemistry, and prion-protein gene analysis of Slovenian cases of Creutzfeldt-Jakob disease from January 1985 to the end of 2003.

MATERIALS, METHODS AND RESULTS

During the 19-year period, 39 suspected cases of Creutzfeldt-Jakob disease were referred and 22 were confirmed. The prion-protein gene was analyzed in 12 of the confirmed cases and the protein glycosylation pattern in 11. There was a low average incidence of Creutzfeldt-Jakob disease (0.5/million) throughout the surveillance period, but a pronounced increase between January 2001 and December 2003 (to 1.9/million/year). A high female to male ratio (2.5/1) was noted. All of the confirmed cases were defined as sporadic Creutzfeldt-Jakob disease based on the clinical data, neuropathological findings, glycosylation pattern, and gene analysis. All tested cases had a type-2 glycosylation pattern; eleven of the twelve tested patients were homozygous at codon 129 of the prion-protein gene (1 VV and 10 MM) and one was heterozygous.

CONCLUSION

The small number of Slovenian cases of sporadic Creutzfeldt-Jakob disease during the last 19 years has shown a pronounced increase in incidence, reflecting improved surveillance, and a high female to male ratio, where female cases are more than twice as numerous as male cases.

The Epidemiology of Variant Creutzfeldt-Jakob Disease

Variant Creutzfeldt-Jakob disease (vCJD) was identified as a new disease in 1996. It was linked to infection with the bovine spongiform encephalopathy (BSE) agent although the epidemiological evidence for this was not strong, but later strain typing studies confirmed the association. The disease has affected predominantly young adults whose dietary and other characteristics are unexceptional compared to control groups, other than that all patients to date have been methoinine homozygous at codon 129 of the prion protein gene and the incidence has been about two times higher in the North of the UK. The number of cases in the 7 years after first identification of the disease has been considerably lower than initially feared, given the likely widespread exposure of the UK population to the BSE agent through contaminated beef products. Predictions of the possible future course of the epidemic have many associated uncertainties, but current mathematical models suggest that more than a few thousand cases is unlikely. Such modelling is limited by the absence of a test for infection with the vCJD agent. The development of a test that could be used on easily accessible tissue to detect infection early in the incubation period would not only advance understanding of the epidemiology of infection with the agent but would also aid the implementation of control measures to prevent potential iatrogenic spread.

Does an infrasonic acoustic shock wave resonance of the manganese 3+ loaded/copper depleted prion protein initiate the pathogenesis of TSE?

Intensive exposures to natural and artificial sources of infrasonic acoustic shock (tectonic disturbances, supersonic aeroplanes, etc.) have been observed in ecosystems supporting mammalian populations that are blighted by clusters of traditional and new variant strains of transmissible spongiform encephalopathy (TSE). But TSEs will only emerge in those 'infrasound-rich' environments which are simultaneously influenced by eco-factors that induce a high manganese (Mn)/low copper (Cu)-zinc (Zn) ratio in brains of local mammalian populations. Since cellular prion protein (PrPc) is a cupro-protein expressed throughout the circadian mediated pathways of the body, it is proposed that PrP's Cu component performs a role in the conduction and distribution of endogenous electromagnetic energy; energy that has been transduced from incoming ultraviolet, acoustic, geomagnetic radiations. TSE pathogenesis is initiated once Mn substitutes at the vacant Cu domain on PrPc and forms a nonpathogenic, protease resistant, 'sleeping' prion. A second stage of pathogenesis comes into play once a low frequency wave of infrasonic shock metamorphoses the piezoelectric atomic structure of the Mn 3+ component of the prion, thereby 'priming' the sleeping prion into its fully fledged, pathogenic TSE isoform - where the paramagnetic status of the Mn 3+ atom is transformed into a stable ferrimagnetic lattice work, due to the strong electron-phonon coupling resulting from the dynamic 'Jahn-Teller' type distortions of the oxygen octahedra specific to the trivalent Mn species. The so called 'infectivity' of the prion is a misnomer and should be correctly defined as the contagious field inducing capacity of the ferrimagnetic Mn 3+ component of the prion; which remains pathogenic at all temperatures below the 'curie point'. A progressive domino-like 'metal to ligand to metal' ferrimagnetic corruption of the conduits of electromagnetic superexchange is initiated. The TSE diseased brain can be likened to a solar charged battery on continuous charge; where the Mn contaminated/Cu depleted circadian-auditory pathways absorb and pile up, rather than conduct the vital life force energies of incoming ultra violet, acoustic and geomagnetic radiation. Instead of harnessing these energies for the body's own bio-rhythmic requirements, an infrasonic shock induced metamorphosis of the Mn atom intervenes; initiating an explosive pathogenesis that perverts the healthy pathways of darkness and light; Cu prions are replaced by hyperpolarized Mn 3+ prions that seed self perpetuating 'cluster bombs' of free radical mediated neurodegeneration. TSE ensues.

Clinical features of variant Creutzfeldt-Jakob disease

Since 1996, over one hundred cases of variant Creutzfeldt-Jakob disease have appeared, mostly in the United Kingdom. In this review, we summarise the major clinical features of this progressive neurodegenerative condition and compare them with those of sporadic Creutzfeldt-Jakob disease. We emphasise the young age (median 26 years) at presentation and the dominant psychiatric/behavioural features, particularly depression. Sensory symptoms are present initially in half the cases and florid psychiatric symptoms, such as delusions or hallucinations, are also common. Given these symptoms, many patients present in clinical practice initially to a psychiatrist but are referred to neurologists when neurological signs become apparent. Although the definitive diagnosis remains neuropathological, a confident pre-mortem diagnosis is now possible when the 'pulvinar sign' is seen on magnetic resonance imaging studies.

Ecosystems supporting clusters of sporadic TSEs demonstrate excesses of the radical-generating divalent cation manganese and deficiencies of antioxidant co factors Cu, Se, Fe, Zn. Does a foreign cation substitution at prion protein's Cu domain initiate TSE?

Analyses of food chains supporting isolated clusters of sporadic TSEs (CWD in N Colorado, scrapie in Iceland, CJD in Slovakia) demonstrate a consistent 2 1/2+ fold greater concentration of the pro-oxidant divalent cation, manganese (Mn), in relation to normal levels recorded in adjoining TSE-free localities. Deficiencies of the antioxidant co factors Cu/Se/Zn/Fe and Mg, P and Na were also consistently recorded in TSE foodchains. Similarities between the clinical/pathological profile of TSEs and Mn delayed psycho-neurotoxicity in miners are cited, and a novel theory generated which suggests that sporadic TSE results from early life dependence of TSE susceptible genotypes on ecosystems characterised by this specific pattern of mineral imbalance. Low Cu/Fe induces an excessive absorption of Mn in ruminants and an increased oxidation of Mn2+ into its pro oxidant species, Mn3+, which accumulates in mitochondria of CNS astrocytes in Mn SOD deficient genotypes. Deficiencies of scavenger co factors Cu/Zn/Se/Fe in the CNS permits Mn3+ initiated chain reactions of auto-oxidant mediated neuronal degeneration to proliferate, which, in turn, up-regulates the expression of the Cu-metalloprotein, prion protein (PrP). Once the rate of PrP turnover and its demand for Cu exceeds the already depleted supply of Cu within the CNS, PrP can no longer bind sufficient Cu to maintain its conformation. Mn3+ substitutes at the vacated Cu domain on PrP, thus priming up a latent capacity for lethal auto-oxidative activity to be carried along with PrP like a 'trojan horse'; where Mn 3+ serves as the integral 'infectious' transmissible component of the misfolded PrP-cation complex. The Mn overactivation of concanavalin A binding to glycoprotein and Mn-initiated autoxidation results in a diverse pathological profile involving receptor capping, aggregation/modification of CNS membrane/cytoskeletal proteins. TSE ensues. The BSE/nv CJD strain entails a 'synthetic' induction of the same CNS mineral disturbance, where 'in utero' exposure to Cu-chelating insecticides/Mn supplements accelerates the onset of a more virulent 'strain' of adolescent TSE.

Is the pathogen of prion disease a microbial protein?

Though considerable circumstantial evidence suggests that the pathogen of prion disease is proteinaceous, it has not yet been conclusively identified. Epidemiological observations indicate that a microbial vector is responsible for the transmission of natural prion disease in sheep and goats and that the real causative agent may correspond to a structural protein of that microorganism. The microbial protein should resemble prion protein (PrP) and may replicate itself in the host by using mammalian DNA. A similar phenomenon was already described with a protein antigen of the ameba Naegleria gruberi. The various serotypes of the microbial protein may account for the existence of scrapie strains. It is proposed that many microbial proteins may be capable of replicating themselves in mammalian cells eliciting and sustaining thereby degenerative and/or autoimmune reactions subsequent to infections with microorganisms.

Creutzfeldt-Jakob disease in Austria

Between 1969 and 30 September 1995, 79 Austrian patients had Creutzfeldt-Jakob disease (CJD) diagnosed neuropathologically by necropsy or biopsy. The annual incidence has significantly increased in recent years (average 0.18 per million in 1969-85, and 0.67 per million in 1986-94; estimate for 1995: 1.5 per million). Also, the percentage of patients with CJD over 70 years at death increased significantly until 1989 but is since in decline. There is no regional clustering, familial occurrence, or recognised iatrogenic risk. One patient had a 10 year history of intramuscular injection of purified bovine RNA preparation (Regeneresen) from various organs including the brian. The ages at death are symmetrically distributed around the median of 64 years. The median duration of disease is four months. Most patients (76%) died within six months of onset. Retrospectively, 86% of patients fulfilled clinical criteria of probable or possible CJD. Neuropathology showed the classic triad of spongiform change, astrogliosis, and neuronal loss in most cases. Two cases did not show unequivocal tissue alterations, but anti-PrP immunocytochemistry detected PrP deposits also in these cases. It is concluded that the recent rise in incidence of CJD in Austria most likely reflects increased awareness and diagnosis of CJD rather than a real increase. As bovine spongiform encephalopathy (BSE) has not been reported in Austria, the data do not support a link between a rise in incidence of sporadic CJD and BSE.

Epidemiology of presenile Alzheimer's disease in Scotland (1974-88) II. Exposures to possible risk factors

BACKGROUND AND METHOD

We related geographical variation of 'probable' presenile Alzheimer's disease (AD PSD) to exposures to possible risk factors for AD PSD and vascular dementia (VaD) and to geographical differences in survival times after presentation with AD PSD.

RESULTS

We found that an ecological measure of socio-economic deprivation was related to VaD but not to AD PSD. Among men with AD PSD and VaD, specific occupations conveyed no altered risk but having fathers who were coal miners was associated with AD PSD and VaD in offspring. Increased paternal age was associated with AD PSD but only in men. These factors acted independently of one another and did not distinguish between geographical areas of high and low incidence.

CONCLUSIONS

The length of survival after presentation with AD PSD distinguished between these areas, and when migration between these areas was taken into account, a plausible multifactorial model of the harmful effects of environment emerged, which acted independently of risk factors acting earlier in life.

Neurodegenerative diseases and risk factors: a literature review

Degenerative diseases of the central nervous system are significant causes of mortality among elderly people in industrialized countries. For the most part, the causes of these diseases are unknown. It is also very difficult to diagnose this type of disease quickly and accurately. This article reviews the epidemiological research on the principal neurodegenerative disorders, focusing on geographical, hereditary and viral and toxicological exposure correlates. We look in particular at the effect of exposure to toxins as well as the effect that deficiencies of elements such as calcium and selenium could have on the development of these neurological diseases. We also consider the possible protectionist effect of some variables on the development of certain neurological diseases.

Inherited Creutzfeldt-Jakob disease in a British family associated with a novel 144 base pair insertion of the prion protein gene

A case of familial Creutzfeldt-Jakob disease associated with a 144 base pair insertion in the open reading frame of the prion protein gene is described. Sequencing of the mutated allele showed an arrangement of six octapeptide repeats, distinct from that of a recently described British family with an insertion of similar size. Thirteen years previously the brother of the proband had died from "Huntington's disease", but re-examination of his neuropathology revealed spongiform encephalopathy and anti-prion protein immunocytochemistry gave a positive result. The independent evolution of at least two distinct pathological 144 base pair insertions in Britain is proposed. The importance of maintaining a high index of suspicion of inherited Creutzfeldt-Jakob disease in cases of familial neurodegenerative disease is stressed.

From slow virus to prion: a review of transmissible spongiform encephalopathies

Spongiform encephalopathies include seven neurodegenerative diseases: three in man (Creutzfeldt-Jakob disease, Gerstmann-Sträussler-Scheinker disease and kuru) and four in animals (scrapie, mink encephalopathy, bovine spongiform encephalopathy and chronic wasting disease in deer and elks). They are all transmissible to a variety of species, and man-to-man propagation of the diseases in the form of iatrogenic transmission has been well-documented. The infectious agent is highly unusual and the pathogenesis of infection remains controversial. The term prion was introduced to describe the proteinaceous infectious agent. Purification of this agent yielded a unique sialoglycoprotein, associated with the neuronal cell membrane, which is all or part of the infectious agent. Molecular genetics revealed variations in the prion protein; these are linked to or associated with the inherited forms of spongiform encephalopathies: familial Creutzfeldt-Jakob disease and Gerstmann-Sträussler-Scheinker disease. The histological triad of spongiform change, neuronal loss and astrocytosis dominate the histological picture of spongiform encephalopathies. A recent case which did not develop any of the histological hallmarks of disease, but did have genetic abnormalities typical of the disease, indicates that the true incidence of Creutzfeldt-Jakob disease may be considerably higher than previously accepted, and a combination of molecular screening and immunohistochemistry for prion protein should complement traditional neuropathology to establish the diagnosis. The descriptive term of spongiform encephalopathy may now have to be abandoned in favour of prion disease.

"Clusters" of CJD in Slovakia: the first statistically significant temporo-spatial accumulations of rural cases

A space-time analysis of clustering among 78 definite CJD cases who died in Slovakia (75) and an adjacent part of Hungary (3) during 1972-1991 is presented. Two geographical rural accumulations of sporadic and familial CJD patients in the north and south of Central Slovakia were found. There was evidence of two significant clusters when spatial and temporal neighborhoods were defined by distances of 2,4,5 and 7 km within 1.5 and 2 years. Involvement of genetic mechanisms in the clusters was demonstrated, and the possible role of environmental (zoonotic) risk factors are considered.

Epidemiological surveillance of Creutzfeldt-Jakob disease in the United Kingdom

Systematic epidemiological surveillance of Creutzfeldt-Jakob disease was carried out in England and Wales covering the years 1970-1984. The results of this work provide a basis from which to assess any change in the pattern of Creutzfeldt-Jakob disease following the occurrence of Bovine Spongiform Encephalopathy. The methodology, early results and problems of the current systematic national survey of CJD, initiated in May 1990, are discussed.

Some new aspects of CJD epidemiology in Slovakia

Descriptive epidemiological and genealogical data obtained by prospective and retrospective studies on CJD in Slovakia and in patients emigrating from CJD clusters were analysed. Observations contradictory to an exclusively genetic etiology of temporo-spatial accumulation of CJD are presented. Data indicating a genetically increased susceptibility to the disease and its coincidence with environmental risk in clustering patients are discussed.

Geographical distribution of cases of Creutzfeldt-Jakob disease in England and Wales 1970-84

Two hundred and sixty seven patients with a definite or probable diagnosis of Creutzfeldt-Jakob disease (CJD) were identified in an attempt to ascertain all cases of the disease in England and Wales in the period 1970-84. No evidence of space-time clustering of dates and places of onset was found for these cases. Two age- and sex-matched controls were selected for 72 of the 122 cases diagnosed in the period 1980-84 and life histories of places of residence were obtained for these cases and the controls. No evidence was found that cases had lived closer to each other than had controls at any time in their lives, except that there was an excess of cases born in London. The study does not provide supportive evidence for case-to-case transmission of CJD being an important component in the aetiology of the disease.

A retrospective study of Creutzfeldt-Jakob disease in Italy (1972-1986)

In a retrospective study of Creutzfeldt-Jakob disease (CJD) in Italy from 1972 to 1986, we found 79 cases which fulfilled the diagnostic criteria for CJD. The annual mortality rate was 0.09 cases per million inhabitants. In this series the female to male ratio was 2.59, a value significantly higher than that found in Italian population (1.05). The mean age at death was 62.1 +/- 9.4 years and the mean duration of the disease was 5.3 +/- 3.0 months. No familial cases of CJD were found in our series. Mental deterioration was present in all of our cases, myoclonus in 85% and the other clinical signs were present at a lower rate. Periodic EEG activity was found in 92% of the cases. Two patients had had neurological or ophthalmic surgery and 17% of our cases had undergone general surgery within 5 years prior to the clinical onset of CJD.

Creutzfeldt-Jakob disease in England and Wales, 1980-1984: a case-control study of potential risk factors

An attempt was made to ascertain all cases of Creutzfeldt-Jakob disease occurring in England and Wales during the 5 year period 1980-1984. The mean annual mortality rate was 0.49/million; women were more frequently affected than men. The age-specific mortality rate reached a peak in the seventh decade. A case-control study involving 92 of the 122 definite and probable cases ascertained failed to confirm the reality of previously suspected aetiological agents in the environment. Although there was no confirmed instance of familial Creutzfeldt-Jakob disease in the case-control study, dementia in close relatives was significantly more common than in controls.

Descriptive epidemiology of Creutzfeldt-Jakob disease in Finland

In 1974-84 30 patients died with a diagnosis of Creutzfeldt-Jakob disease (CJD) in Finland. Sixteen of the patients were pathologically confirmed and 14 were probable cases; 6 were familial (20%). One further familial patient was alive at the end of 1984. The median age of the 30 patients at death was 59.5 years (range 46-73 years). The familial patients were significantly younger than sporadic cases (median and range 49.5 and 46-57 versus 61.5 and 51-73; P less than 0.01). Only 5 of the 24 sporadic patients were men (male to female ratio 1:3.8). The annual number of new cases as well as the death rate increased in the late 1970's (annual death rate 0.57 per million in 1974-84 and 0.91 in 1979-84). This probably reflects the growing awareness of CJD among neurologists, rather than a real increase of the incidence and death rate. Annual age-specific death rate per 1 million population in 1974-84 reached a peak value of 2.57 in the age group of 60-64 years. In sporadic CJD the age-specific death rate of women was higher than that of men in all age groups. A chronic medical condition, precedent or concomitant with CJD, was seen in 15 patients.