Exploring CJD incidence trends: insights from Slovakia

Authors are commenting on the evolving geographical incidence trends observed with the genetic form of Creutzfeldt-Jakob disease and discussing the diverse array of factors contributing to the heightened incidence rates observed in specific geographical regions.

Understanding Creutzfeldt-Jakob disease in Iran: a systematic review of case reports

OBJECTIVE

To systematically review the reported cases of Creutzfeldt-Jakob disease (CJD) in Iran.

METHODS

A comprehensive literature review of CJD cases in Iran was undertaken using the PubMed®, Scopus® and Google Scholar databases. In addition, the Iranian database MagIran was searched for Persian language reports. Case selection used the following criteria: (i) patients of Iranian origin; (ii) publication in peer-reviewed journals or reputable medical databases; (iii) a definitive diagnosis of CJD based on established diagnostic criteria.

RESULTS

Thirteen cases from twelve reports were included in this systematic review. The majority of the cases were female (11 of 13; 84.6%). The mean ± SD age of patients at hospital admission was 59.38 ± 7.44 years. The findings of the case review suggested that the prevalence of CJD in Iran is not fully established. CJD may be misdiagnosed alongside other clinical signs. The most prevalent early indications of the disease were psychiatric and neurological in nature. A considerable delay in diagnosis was observed in some cases and there was a shortage of brain autopsy records.

CONCLUSION

Efforts to improve diagnostic capabilities, promote awareness and establish monitoring systems are necessary for managing the challenges of providing an early diagnosis of CJD in Iran.

Sporadic Creutzfeldt-Jakob disease in adults over 80 years: a 10-year review of United Kingdom surveillance

INTRODUCTION

Sporadic Creutzfeldt-Jakob disease (sCJD) is a rapidly progressive neurodegenerative disease with public health implications. Mean age of onset is 68 years. Age-specific incidence declines after 80 years. This may arise from under-ascertainment or other biological features of the disease. Accurate characterisation of late-onset sCJD is important for early diagnosis, avoiding unnecessary investigations and improving ascertainment for public health purposes.

OBJECTIVE

To phenotype the clinical features and investigation profile of sCJD in adults >80 years.

METHODS

We analysed all probable and definite sCJD cases identified by the UK National CJD Research & Surveillance Unit over a 10-year period (2011-2021). Individuals were grouped by age of onset. Clinical features and investigation profiles were compared.

RESULTS

10.3% (123/1196) had an age of onset over 80. Median survival was shorter (3.2 vs 4.3 months; P < 0.001). Pyramidal signs (48.3% vs 34.2%; P = 0.008) and akinetic mutism (55.1% vs 33.2%; P < 0.001) were more frequent. Psychiatric symptoms (26.3% vs 39.6%; P = 0.01) and cerebellar signs (65.4% vs 78.6%, P = 0.007) were less frequent. Cognitive impairment and myoclonus were highly prevalent regardless of age. Between age groups, the diagnostic sensitivity of cerebrospinal fluid real-time quaking-induced conversion (CSF RT-QuIC) (92.9% vs 91.9%, P = 0.74) was comparable, electroencephalography was superior (41.5% vs 25.4%; P = 0.006) and MRI was inferior (67.8% vs 91.4%; P < 0.001).

CONCLUSIONS

Late-onset sCJD has distinct clinical features, shorter survival and a different profile of investigation sensitivity. CSF RT-QuIC, MRI brain and specialist CJD review is recommended in older adults with a rapidly progressive neurological disorder. Autopsy is valuable when the cause remains elusive.

Enhanced Creutzfeldt-Jakob disease surveillance in the older population: Assessment of a protocol for screening brain tissue donations for prion disease

Human prion diseases, including Creutzfeldt-Jakob disease (CJD), occur in sporadic, genetic, and acquired forms. Variant Creutzfeldt-Jakob disease (vCJD) first reported in 1996 in the United Kingdom (UK), resulted from contamination of food with bovine spongiform encephalopathy. There is a concern that UK national surveillance mechanisms might miss some CJD cases (including vCJD), particularly in the older population where other neurodegenerative disorders are more prevalent. We developed a highly sensitive protocol for analysing autopsy brain tissue for the misfolded prion protein (PrPSc ) associated with prion disease, which could be used to screen for prion disease in the elderly. Brain tissue samples from 331 donors to the Edinburgh Brain and Tissue Bank (EBTB), from 2005 to 2022, were analysed, using immunohistochemical analysis on fixed tissue, and five biochemical tests on frozen specimens from six brain regions, based on different principles for detecting PrPSc . An algorithm was established for classifying the biochemical results. To test the effectiveness of the protocol, several neuropathologically confirmed prion disease controls, including vCJD, were included and blinded in the study cohort. On unblinding, all the positive control cases had been correctly identified. No other cases tested positive; our analysis uncovered no overlooked prion disease cases. Our algorithm for classifying cases was effective for handling anomalous biochemical results. An overall analysis suggested that a reduced biochemical protocol employing only three of the five tests on only two brain tissue regions gave sufficient sensitivity and specificity. We conclude that this protocol may be useful as a UK-wide screening programme for human prion disease in selected brains from autopsies in the elderly. Further improvements to the protocol were suggested by enhancements of the in vitro conversion assays made during the course of this study.

Change in Epidemiology of Creutzfeldt-Jakob Disease in the US, 2007-2020

This cross-sectional study uses Centers for Disease Control and Prevention multiple cause of death data to examine recent US trends in Creutzfeldt-Jakob disease.

A review of the enhanced CJD surveillance feasibility study in the elderly in Scotland, UK

BACKGROUND

Variant Creutzfeldt - Jakob disease (vCJD) arose from dietary contamination with bovine-spongiform-encephalopathy (BSE). Because of concerns that vCJD-cases might be missed in the elderly, a feasibility study of enhanced CJD surveillance on the elderly was begun in 2016. Recruitment was lower than predicted. We describe a review of the challenges encountered in that study: identification, referral, and recruitment, and the effects of actions based on the results of that review.

METHODS

Review was conducted in 2017. Study data for all eligible cases identified and referred from one participating service (Anne Rowling clinic (ARC)) was curated and anonymised in a bespoke database. A questionnaire was sent out to all the clinicians in medicine of the elderly, psychiatry of old age and neurology (including ARC) specialties in NHS Lothian, exploring possible reasons for low recruitment.

RESULTS

Sixty-eight cases were referred from the ARC (March 2016-September 2017): 25% were recruited. Most cases had been referred because of diagnostic uncertainty. No difference was seen between those recruited and the non-recruited, apart from age and referrer. Twelve of 60 participating clinicians completed the questionnaire: only 4 had identified eligible cases. High workload, time constraints, forgetting to refer, unfamiliarity with the eligibility criteria, and the rarity of eligible cases, were some of the reasons given. Suggestions as to how to improve referral of eligible cases included: regular email reminders, feedback to referrers, improving awareness of the study, visible presence of the study team, and integration of the study with other research oriented services. These results were used to increase recruitment but without success.

CONCLUSION

Recruitment was lower than predicted. Actions taken following a review at 21 months did not lead to significant improvement; recruitment remained low, with many families/patients declining to take part (75%). In assessing the failure to improve recruitment, two factors need to be considered. Firstly, the initial referral rate was expected to be higher because of existing patients already known to the clinical services, with later referrals being only newly presenting patients. Secondly, the unplanned absence of a dedicated study nurse. Searching digital records/anonymised derivatives to identify eligible patients could be explored.

Effect of SARS-CoV-2 Incidence and Immunisation Rates on Sporadic Creutzfeldt-Jakob Disease Incidence

BACKGROUND

Recent case studies and media outlets have hypothesised an effect of SARS-CoV-2 infection and immunisation on the development or progression of neurodegenerative diseases such as Alzheimer's disease or sporadic Creutzfeldt-Jakob disease (sCJD).

OBJECTIVES

This study aims to identify potential associations of SARS-CoV-2 infections and SARS-CoV-2 immunisation with sCJD incidence, disease duration, and age of onset.

METHOD

We used data from a prospective sCJD surveillance study in Germany (2016-2022) and publicly available datasets of SARS-CoV-2 cases and vaccination numbers in Germany for the years 2020-2022. Associations of SARS-CoV-2 incidence and immunisation rates with sCJD incidence were assessed by comparing quarterly and annual cumulative sCJD incidences in the periods before (2016-2019) and during the pandemic (2020-2022).

RESULTS

We could not identify any time-related effect of SARS-CoV-2 incidence or immunisation rate on the sCJD incidence. Moreover, we did not find any sCJD incidence alterations before and during the SARS-CoV-2 pandemic on a federal or state level. The overall sCJD incidence was within expected ranges in the years 2020-2022. There were no changes in age of onset and clinical disease duration in these years.

CONCLUSIONS

We found no evidence supporting a short-term effect of the pandemic on sCJD incidence. However, considering the extended pre-clinical phase of sCJD, continued surveillance is needed to identify potential future incidence alterations.

Prospective 25-year surveillance of prion diseases in France, 1992 to 2016: a slow waning of epidemics and an increase in observed sporadic forms

BackgroundPrion diseases are rare, fatal disorders that have repeatedly raised public health concerns since the early 1990s. An active prion disease surveillance network providing national level data was implemented in France in 1992.AimWe aimed to describe the epidemiology of sporadic, genetic and infectious forms of prion diseases in France since surveillance implementation.MethodsWe included all suspected cases notified from January 1992 to December 2016, and cases who died during the period with a definite or probable prion disease diagnosis according to EuroCJD criteria. Demographic, clinical, genetic, neuropathological and biochemical data were collected.ResultsIn total, 25,676 suspected cases were notified and 2,907 were diagnosed as prion diseases, including 2,510 (86%) with sporadic Creutzfeldt-Jakob disease (sCJD), 240 (8%) genetic and 157 (6%) with infectious prion disease. Suspected cases and sCJD cases increased over time. Younger sCJD patients (≤ 50 years) showed phenotypes related to a distinct molecular subtype distribution vs those above 50 years. Compared to other European countries, France has had a higher number of cases with iatrogenic CJD after growth hormone treatment and variant CJD (vCJD) linked to bovine spongiform encephalopathy (second after the United Kingdom), but numbers slowly decreased over time.ConclusionWe observed a decrease of CJD infectious forms, demonstrating the effectiveness of measures to limit human exposure to exogenous prions. However, active surveillance is needed regarding uncertainties about future occurrences of vCJD, possible zoonotic potential of chronic wasting diseases in cervids and increasing trends of sCJD observed in France and other countries.

The epidemiological and clinical characteristics of patients with young-onset genetic Creutzfeldt-Jakob disease

OBJECTIVES

The onset of Creutzfeldt-Jakob disease (CJD) is usually around the age of 60, but younger patients have been described as well. Our study characterizes the demographic and clinical features of young-onset CJD patients.

METHODS

The CJD Israeli National Database was reviewed, and the patients were divided into groups of young (<40-year-old) (Y|) and older disease onset (>40-year-old) (O). Each group was further divided into sporadic (sCJD) and genetic (gCJD) patients. Clinical and demographic parameters were compared between the groups.

RESULTS

The study included 731 patients (Y- 18 patients, O- 713 patients). MRI showed classical features more often in the older population (O-76.9%, Y-36%, p = 0.006). Rapidly progressive dementia as a presenting feature was more common in the older group (O = 58%, Y = 27.7%, p = 0.019) whereas cerebellar onset (gait instability, dysarthria) was more common in the younger group (O = 6.7%, Y = 27.7%, p = 0.036)). Among gCJD patients, rapidly progressive dementia was commonly seen in older patients (O = 54%, Y = 21% p = 0.008) whereas cerebellar symptoms were seen in young patients (O = 7%, Y = 30% p = 0.01) Typical MRI findings were seen in 37% of young people compared to 87% of older patients (p = 0.002). No significant differences were between young and older patients in the sCJD group.

CONCLUSION

Young-onset gCJD patients have unique disease features including less typical brain MRI changes, a lower prevalence of dementia, and a higher prevalence of cerebellar signs at disease onset.

Risk of variant Creutzfeldt-Jakob disease in a simulated cohort of Canadian blood donors

BACKGROUND AND OBJECTIVES

No transfusion-associated cases of variant Creutzfeldt-Jakob disease (vCJD) have occurred in more than 20 years. Yet, many countries have maintained blood donor deferral criteria for vCJD. We developed a risk simulation model to reassess the need for vCJD-related deferral criteria in Canada.

MATERIALS AND METHODS

The model provides results separately for Héma-Québec (HQ) and Canadian Blood Services (CBS). The model used a Monte Carlo simulation approach to estimate the risk of having a vCJD-contaminated blood donation ('risk of vCJD') in a simulated cohort of 10 million donors followed for up to 85 years. The model assumed current deferral criteria for vCJD were lifted, which would allow new 'at-risk' donors to give blood. The model accounted for disease prevalence, donors' travel/immigration history, PRNP genotype at codon 129, demographics and the type of labile blood product.

RESULTS

In the base case, the risk of vCJD was estimated at zero at both blood services. In the most pessimistic scenario, the risk of vCJD was 6.4 × 10-9 (i.e., 1 in 157 million donations) at HQ, or ≤1 in 77 million based on the upper bound of the 95% confidence interval (CI). At CBS, this risk was 4.8 × 10-8 (i.e., 1 in 21 million donations), or ≤1 in 16 million based on the upper bound of the 95% CI.

CONCLUSION

vCJD poses minimal risks to the Canadian blood supply. Current vCJD deferral criteria may, therefore, be lifted with virtually no impact on safety, while significantly expanding the donor base.

Low risk of variant Creutzfeldt-Jakob disease transmission from blood transfusions in Aotearoa New Zealand suggests donor exclusion policies can be relaxed

Aotearoa New Zealand currently excludes potential blood donors who lived in the United Kingdom (UK) for 6 months or more between 1980 and 1996. This action is due to the potential for variant Creutzfeldt-Jakob disease (vCJD) following blood transfusions from preclinical vCJD cases, who themselves mostly developed disease from the consumption of cattle with bovine spongiform encephalopathy (BSE) during this period, or from those incubating the misfolded prion proteins that cause disease. This donor exclusion policy led to 10% of New Zealand's active blood donors in 2000 being excluded, and it remains today despite periodic shortages of some blood products. Globally there have been 232 vCJD cases recorded-178 in the UK-with no new cases since 2019 and the peak numbers 23 years ago in 2000. Only three confirmed cases have been linked to blood transfusion. Here, we aimed to estimate the annual risk of vCJD from blood transfusion in New Zealand after restriction removal. We used UK case numbers, population estimates, and donor and recipient transfusion numbers to calculate the risk to the New Zealand public. We calculated the risk, based on approximately 131,000 transfusions a year and accounting for multiple transfusions, might lead to 0.005 cases annually, or approximately one in one billion nationally, and comparable to recent one in 1.45 billion estimates for Australia. Our analyses suggests that relaxing current blood donation restrictions, like Ireland and Australia's recent policy changes, would lead to an extremely low risk of vCJD transfusion-transmission in New Zealand. This policy change would help increase the supply of blood products for multiple medical needs.

Transmission of Variant Creutzfeldt-Jakob Disease Through Blood Transfusion and Plasma-Derived Products: A Narrative Review of Observed and Modeled Risks

Secondary transmission of variant Creutzfeldt-Jakob disease (vCJD) can occur through blood transfusion or receipt of plasma-derived products. However, published reviews on this topic are outdated, focused on a single country or product type, or did not comprehensively review modeling studies on the risk of transfusion-transmission. We reviewed existing data on observed and modeled risks of transfusion-transmission of vCJD. To date, five patients are suspected to have acquired clinical vCJD or a vCJD infection after receiving a blood or plasma-derived product from a donor who later developed clinical vCJD. All of these cases received a nonleukodepleted blood-derived product in the United Kingdom between 1994 and 1999. Thus, all transfusion-associated cases occurred before the adoption of universal leukodepletion in 1999, which supports the preferential tropism of vCJD for leukocytes. In descriptive cohort studies, no cases of clinical vCJD were observed over ∼13 years of follow-up. In modeling studies, the risk of collecting a contaminated donation was generally <23 per million donations, that of infection was generally <10 per million transfusions or doses, and that of clinical vCJD was generally <2 per million transfusions or doses. These low risk estimates and the two-decade long absence of new cases of transfusion-associated vCJD suggest vCJD poses minimal risks to the safety of the blood supply. Furthermore, despite concerns of a second wave driven by individuals harboring a non-MM genotype at codon 129 of PRNP, there has been only 1 autopsy-confirmed case of clinical vCJD in an MV individual in 2016. The current trend to reassess or (in some countries) fully withdraw the blood donation criteria related to vCJD therefore seems justified, safe, and may significantly expand the donor base.

Is There Horizontal Transmission of Creutzfeldt-Jakob Disease?

BACKGROUND

Sporadic Creutzfeldt-Jakob disease (s-CJD) is a rare, fatal neurodegenerative disorder. Familial cases of Creutzfeldt-Jakob disease (f-CJD) due to mutations in the PRNP gene are even rarer around the world; however, in Israel there is a focus of f-CJD patients carrying the E200K mutation. As the number of CJD E200K carriers in Israel is high and increasing, transmission of CJD to normal people was suspected. If such transmission occurs, the incidence of s-CJD would be expected to increase as well, resulting in changes of the ratio of familial/sporadic cases.

METHODS

Using data from the National CJD Registry and official statistics on the Israeli population, we studied incidence rates of f-CJD and s-CJD for the period from 1985 to 2018 applying the Surveillance Epidemiology and End Results (SEER) statistical packet developed in the US National Cancer Institute.

RESULTS

In total, 621 CJD patients (405 f-CJD and 216 s-CJD) cases are included in the registry. In the cohort of f-CJD patients, the mean age-adjusted annual incidence rate over the abovementioned period was 1.88 ± 0.09 (95% CI: 1.7-2.08) per 1,000,000. In the cohort of s-CJD patients, the mean age-adjusted incidence rate over the same period was 0.93 ± 0.06 (95% CI: 0.81-1.06) per 1,000,000 people. No significant time trends were found over the observation period in either s-CJD or f-CJD. The ratio f-CJD/s-CJD decreases over the observation period from 2.2 to 1.80.

CONCLUSION

Israel has a high predominance of f-CJD compared to s-CJD. The mean incidence rate of s-CJD in Israel is similar to most countries. Between 1985 and 2018, the annual age-adjusted incidence rates for both forms of CJD remained stable. Thus, there is no evidence that CJD is transmitted from affected individuals to others.

Application of real-time quaking-induced conversion in Creutzfeldt-Jakob disease surveillance

BACKGROUND

Evaluation of the application of CSF real-time quaking-induced conversion in Creutzfeldt-Jakob disease surveillance to investigate test accuracy, influencing factors, and associations with disease incidence.

METHODS

In a prospective surveillance study, CSF real-time quaking-induced conversion was performed in patients with clinical suspicion of prion disease (2014-2022). Clinically or histochemically characterized patients with sporadic Creutzfeldt-Jakob disease (n = 888) and patients with final diagnosis of non-prion disease (n = 371) were included for accuracy and association studies.

RESULTS

The overall test sensitivity for sporadic Creutzfeldt-Jakob disease was 90% and the specificity 99%. Lower sensitivity was associated with early disease stage (p = 0.029) and longer survival (p < 0.001). The frequency of false positives was significantly higher in patients with inflammatory CNS diseases (3.7%) than in other diagnoses (0.4%, p = 0.027). The incidence increased from 1.7 per million person-years (2006-2017) to 2.0 after the test was added to diagnostic the criteria (2018-2021).

CONCLUSION

We validated high diagnostic accuracy of CSF real-time quaking-induced conversion but identified inflammatory brain disease as a potential source of (rare) false-positive results, indicating thorough consideration of this condition in the differential diagnosis of Creutzfeldt-Jakob disease. The surveillance improved after amendment of the diagnostic criteria, whereas the incidence showed no suggestive alterations during the COVID-19 pandemic.

Sporadic Creutzfeldt-Jakob Disease in the young (50 and below): 10-year review of United Kingdom surveillance

INTRODUCTION

Sporadic Creutzfeldt-Jakob Disease (sCJD) is the commonest human prion disease, with a median age of onset of 68 years. We characterise the clinical, investigation, and neuropathological features in young individuals with sCJD using data from UK national CJD surveillance.

METHODS

Referrals between 2011 and 2021 were examined, with definite (post-mortem confirmed) or probable sCJD cases included. Clinical features, MRI, EEG, CSF RT-QuIC, 14-3-3, PRNP sequencing and neuropathological findings were examined. We compared younger (≤ 50 years age of onset) with older individuals. Records of Non-sCJD referrals were also reviewed.

RESULTS

46 (4%) young individuals were identified (age at onset 25-50) from 1178 cases. 15 (33%) were autopsy confirmed. Psychiatric disturbance (37% vs 22%, p = 0.02) and headache (11% vs 3%, p = 0.01) at presentation, and longer disease duration (by 1.45 months, 95% CI 0.43-2.79, logrank p = 0.007) were commoner. CSF RT-QuIC showed lower sensitivity (82% vs 93%, p = 0.02). There was no difference in sensitivity of MR brain or CSF 14-3-3. There were no significant co-pathologies in autopsy-confirmed cases. For non-sCJD referrals, 41 cases were of other CJD subtypes, and 7 non-prion diagnoses.

CONCLUSIONS

Young-onset sCJD is more likely to present with neuropsychiatric symptoms and headache, longer disease duration, and lower sensitivity of RT-QuIC. These findings may be driven by the underlying molecular subtypes. Our results guide the evaluation of younger individuals presenting with rapidly progressive cognitive, neuropsychiatric, and motor decline, and emphasise the need for additional vigilance for atypical features by clinicians and CJD surveillance programmes worldwide.

[Prion diseases in The Netherlands: twenty-nine years of surveillance]

Prion diseases are being monitored in The Netherlands since 29 years, the national registry is coordinated by Erasmus Medical Center. Since 2010, yearly on average 31 new patients are diagnosed with prion disease. There is a slight increase in incidence of prion diseases, probably due to better recognition and improved diagnostics. The most recent development in the diagnostic is the real-time quaking-induced conversion (RT-QuIC) test, which can detect prion proteins in cerebrospinal fluid with high sensitivity and specificity. The polymorphism of codon 129 of the prion gene (PRNP) determines the susceptibility for the different subtypes of Creutzfeldt-Jakob disease (CJD) and influences the clinical course. Awareness for atypical presentations of CJD and for CJD mimics is important, such as autoimmune encephalitis, which is often treatable and can resemble CJD.

Creutzfeldt-Jakob Disease Incidence, South Korea, 2001-2019

We found increasing trends of Creutzfeldt-Jakob disease (CJD) cases and annual incidence in South Korea during 2001-2019. We noted relatively low (5.7%) distribution of familial CJD. An unusually high percentage (≈1%) of patients were in the 30-39 age group, which should prompt a preemptive CJD control system.

Creutzfeldt-Jakob Disease in South West Sydney 2014-2020: An Unusually High Incidence of a Rare Disease

INTRODUCTION

Creutzfeldt-Jakob disease (CJD), a spongiform encephalopathy, caused by a transmissible misfolded cellular prion protein, is a rapidly progressive, debilitating neurodegenerative disorder with no effective treatment. The estimated global incidence is at 1/million inhabitants. This retrospective study examined the incidence of CJD in South Western Sydney Local Health District (SWSLHD) from 2014 to 2020.

BACKGROUND

SWSLHD had an estimated population of 1,038,534 in 2020, with CJD data being limited.

METHODS

The New South Wales (NSW) Health Information Exchange (HIE) database, for all admissions with CJD diagnoses in SWSLHD, between 2014 and 2020, was reviewed according to the WHO diagnostic criteria, consistent with the Australian national CJD registry. Only probable CJD cases were included. Incidence was calculated based on the projected SWSLHD population.

RESULTS

Thirty-five patients, diagnosed with CJD, were identified. Each was evaluated by 2 independent investigators, including clinical presentation, MRI, EEGs, 14-3-3, and RT-QuIC results, before assigning CJD-probable status. Four failed the CJD criteria and were excluded. Of the 31 CJD-probable cases, most (59%) were male and older (37%, range 61-70 years). The incidence rate peaked at 9/million in 2017 and was above 2/million, throughout the 7 years, with an average of 4.859/million/year.

CONCLUSIONS

The incidence of CJD, in SWSLHD, exceeds the national average of 1/million. Cost-effective, adequate diagnostic and screening tools, implementable over a large population, will become increasingly essential.

Progressive multifocal leukoencephalopathy and Creutzfeldt-Jakob disease: population-wide incidences, comorbidities, costs of care, and outcomes

Neurological disorders associated with chronic infections are often progressive as well as challenging to diagnose and manage. Among 4.4 million persons from 2004 to 2019 receiving universal health, progressive multifocal leukoencephalopathy (PML, n = 58) and Creutzfeldt-Jakob disease (CJD, n = 93) cases were identified, revealing stable yearly incidence rates with divergent comorbidities: HIV/AIDS affected 37.8% of PML cases while cerebrovascular disease affected 26.9% of CJD cases. Most CJD cases died within 1 year (73%) although PML cases lived beyond 5 years (34.1%) despite higher initial costs of care. PML and CJD represent important neurological disorders with evolving risk variables and impact on health care.

First participant diagnosed with Creutzfeldt-Jakob disease in the population-based Rotterdam Study was classified with mild cognitive impairment

Sporadic Creutzfeldt-Jakob disease (sCJD) is a rare, fatal, neurodegenerative disease caused by accumulation of abnormally folded prion protein. sCJD can have a long asymptomatic incubation period, with little known about this period. We describe the first-ever participant within the population-based Rotterdam Study diagnosed with sCJD. We retrieved clinical data from both the population-based Rotterdam Study and the National Prion Disease Registry. In 2011, a female participant of the Rotterdam Study was diagnosed with probable sCJD and registered into the Registry. Four months earlier, she was classified as having mild cognitive impairment based on assessment in the Rotterdam Study. Clinical deterioration was rapid, with the patient dying 7 months after the research centre visit. Postmortem brain autopsy confirmed the diagnosis of sCJD. In conclusion, we describe the first case diagnosed with sCJD who during diagnostic workup for sCJD was classified as having mild cognitive impairment in a population-based cohort study.

[Creutzfeldt-Jakob Disease]

Sporadic Creutzfeldt-Jacob disease(sCJD)is a prion disease presenting with subacute or rapidly progressive dementia with a poor prognosis. Asymmetrical cortical lesions with thalamic involvement are found in sCJD cases, which is similar distribution to status epileptics, but the lesions are not observed in the limbic systems, and they rarely occur in the precentral gyrus. Characteristically, hyperintense abnormal findings are more prominent on DWI than on FLAIR and T2WI. 19.9% of CJD is genetic CJD(gCJD), and CJD with a mutation of codon 180 from valine to isoleucine(V180I)accounts for 40% of gCJD in Japan. Patients with this type of gCJD rarely have a family history because of the low penetration rate. The age of onset is usually later, and its clinical symptoms deteriorate more slowly than sCJD. DWI shows abnormal cortical hyperintense signals(cortical ribboning).

Application of telehealth for comprehensive Creutzfeldt-Jakob disease surveillance in the United Kingdom

Creutzfeldt-Jakob disease (CJD) is a fatal human prion disease. Surveillance systems operate globally with the goals of accurate in-life case ascertainment, appropriate public health interventions to minimise secondary transmission, and monitoring trends in disease epidemiology. The UK experienced the highest incidence of variant CJD (vCJD) in the world following widespread population exposure to bovine spongiform encephalopathy (BSE). 178 cases of vCJD have been identified in the UK by the National CJD Research & Surveillance Unit (NCJDRSU), including three cases of secondary transmission via blood transfusion. The NCJDRSU performs high-fidelity surveillance, assessing all cases of suspected CJD referred to the unit. COVID-19 has caused widespread disruption to healthcare and poses a threat to services. The NCJDRSU converted to telehealth-based surveillance in March 2020. We report the results of the application of telehealth for comprehensive CJD surveillance during the first four months of the pandemic. 59 cases were assessed for suspected CJD. In 52 cases the relatives were interviewed for an informant history, by video conference or telephone call. 34 patients underwent video examination; 1 case was examined in-person. MRI images were assessed in all cases and 46 underwent CSF testing. Feedback was obtained from interviewees and the NCJDRSU team on their experiences. 50 cases were diagnosed with sporadic CJD; 5 received an alternative diagnosis, and the remaining 4 remained unresolved, with further investigations underway. Telehealth significantly reduced time taken to assessment compared to in-person assessments in 2019. Telehealth is an effective way to provide comprehensive CJD surveillance at a national level.

Creutzfeldt-Jakob Disease: In-hospital demographics report of national data in the United States from 2016 and review of a rapidly-progressive case

BACKGROUND

This report highlights a rapidly progressive case of Creutzfeldt-Jakob Disease (CJD) whose time from symptom onset to death spanned less than two months. We also explore the most recently available in-patient demographics data for discharges with CJD in the United States.

METHODS

We reviewed a CJD case and systematically analyzed a retrospective cohort of CJD discharges using the Healthcare Cost and Utilization Project (HCUP) to evaluate the existing national data on the status of CJD demographics and dispositions in the United States in 2016.

RESULTS

An estimated total of 710 hospital discharges with a diagnosis of CJD were seen across the United States in 2016. According to HCUP, the average age of patients was 66.15 ± 11.54 years with 48.6 % female. Average time to intubation from admission to hospital was 4.71 ± 7.32 days with a rate of intubation of 6.34 %. The mean hospital cost was $19,901.25 ± $18,743.48. The rate of in-hospital mortality was 8.45 %. No significant geographical differences were noted (p = 0.49). No significant differences were seen among incidence in specific ethnic groups (p = 0.33) or income quartiles (p = 0.90).

CONCLUSIONS

Our data shows that the incidence of CJD in 2016 appears to be equally distributed among individuals in the United States by demographic categories. Additionally, our case-study from 2019 illustrates an important example for diagnosing a rapidly-progressing case of CJD.

Identification of novel risk loci and causal insights for sporadic Creutzfeldt-Jakob disease: a genome-wide association study

BACKGROUND

Human prion diseases are rare and usually rapidly fatal neurodegenerative disorders, the most common being sporadic Creutzfeldt-Jakob disease (sCJD). Variants in the PRNP gene that encodes prion protein are strong risk factors for sCJD but, although the condition has similar heritability to other neurodegenerative disorders, no other genetic risk loci have been confirmed. We aimed to discover new genetic risk factors for sCJD, and their causal mechanisms.

METHODS

We did a genome-wide association study of sCJD in European ancestry populations (patients diagnosed with probable or definite sCJD identified at national CJD referral centres) with a two-stage study design using genotyping arrays and exome sequencing. Conditional, transcriptional, and histological analyses of implicated genes and proteins in brain tissues, and tests of the effects of risk variants on clinical phenotypes, were done using deep longitudinal clinical cohort data. Control data from healthy individuals were obtained from publicly available datasets matched for country.

FINDINGS

Samples from 5208 cases were obtained between 1990 and 2014. We found 41 genome-wide significant single nucleotide polymorphisms (SNPs) and independently replicated findings at three loci associated with sCJD risk; within PRNP (rs1799990; additive model odds ratio [OR] 1·23 [95% CI 1·17-1·30], p=2·68 × 10^-15; heterozygous model p=1·01 × 10^-135), STX6 (rs3747957; OR 1·16 [1·10-1·22], p=9·74 × 10^-9), and GAL3ST1 (rs2267161; OR 1·18 [1·12-1·25], p=8·60 × 10^-10). Follow-up analyses showed that associations at PRNP and GAL3ST1 are likely to be caused by common variants that alter the protein sequence, whereas risk variants in STX6 are associated with increased expression of the major transcripts in disease-relevant brain regions.

INTERPRETATION

We present, to our knowledge, the first evidence of statistically robust genetic associations in sporadic human prion disease that implicate intracellular trafficking and sphingolipid metabolism as molecular causal mechanisms. Risk SNPs in STX6 are shared with progressive supranuclear palsy, a neurodegenerative disease associated with misfolding of protein tau, indicating that sCJD might share the same causal mechanisms as prion-like disorders.

FUNDING

Medical Research Council and the UK National Institute of Health Research in part through the Biomedical Research Centre at University College London Hospitals National Health Service Foundation Trust.

A nationwide trend analysis in the incidence and mortality of Creutzfeldt-Jakob disease in Japan between 2005 and 2014

In the era of hyper-ageing, Creutzfeldt-Jakob disease (CJD) can become more prevalent as an important cause of dementia. This study aimed to evaluate the trends in crude and age-adjusted CJD-associated mortality and incidence rates in Japan using national vital statistics data on CJD-associated deaths among individuals aged over 50 years, as well as the government-funded nationwide CJD surveillance data (pertaining to the years 2005-2014) in Japan. The data were analysed using the Joinpoint Regression Program to estimate the long-term trends and average annual percentage changes (AAPCs). Overall, the AAPCs of age-adjusted CJD-associated mortality rates rose significantly over the study period (3.2%; 95% confidence interval [CI] 1.4-5.1%). The AAPC of the age-adjusted incidence rates also increased (overall 6.4%; 95% CI 4.7-8.1%). The CJD-associated increases in the mortality and incidence rates were especially prominent among adults over the age of 70 years. Given this trend in aging of population, the disease burden of CJD will continue to increase in severity. Our findings thus recommend that policymakers be aware of the importance of CJD and focus on preparing to address the increasing prevalence of dementia.

Sporadic Creutzfeldt-Jakob Disease among Physicians, Germany, 1993-2018

sCJD patients were significantly more likely than the general population to be physicians.

We investigated sporadic Creutzfeldt-Jakob disease (sCJD) among physicians in Germany by analyzing occupational information of patients with sCJD recorded by the German CJD Surveillance Unit (1993–2005; 1,250 patients, of whom 4 [0.32%] were physicians) and the National Reference Center for Human Spongiform Encephalopathies (2006–2016; 1,491 patients, of whom 13 [0.87%] were physicians). Among the physicians, we did not identify any neurologists, neurosurgeons, psychiatrists, or pathologists. A cumulative sum test showed an increase in reported physicians over time. Data for 2017–2018 indicated an increased rate of physicians among all notified sCJD cases (5/239 [2.1%]) when we used the total population of Germany as control group. Our data suggest the possibility of an increased risk for sCJD among physicians in Germany. However, we can only speculate about the reasons, and larger multinational studies are needed to replicate the finding and to clarify whether this finding is a general or a country-specific phenomenon.

Prevalence in Britain of abnormal prion protein in human appendices before and after exposure to the cattle BSE epizootic

Widespread dietary exposure of the population of Britain to bovine spongiform encephalopathy (BSE) prions in the 1980s and 1990s led to the emergence of variant Creutzfeldt-Jakob Disease (vCJD) in humans. Two previous appendectomy sample surveys (Appendix-1 and -2) estimated the prevalence of abnormal prion protein (PrP) in the British population exposed to BSE to be 237 per million and 493 per million, respectively. The Appendix-3 survey was recommended to measure the prevalence of abnormal PrP in population groups thought to have been unexposed to BSE. Immunohistochemistry for abnormal PrP was performed on 29,516 samples from appendices removed between 1962 and 1979 from persons born between 1891 through 1965, and from those born after 1996 that had been operated on from 2000 through 2014. Seven appendices were positive for abnormal PrP, of which two were from the pre-BSE-exposure era and five from the post BSE-exposure period. None of the seven positive samples were from appendices removed before 1977, or in patients born after 2000 and none came from individuals diagnosed with vCJD. There was no statistical difference in the prevalence of abnormal PrP across birth and exposure cohorts. Two interpretations are possible. Either there is a low background prevalence of abnormal PrP in human lymphoid tissues that may not progress to vCJD. Alternatively, all positive specimens are attributable to BSE exposure, a finding that would necessitate human exposure having begun in the late 1970s and continuing through the late 1990s.

Diagnostic Accuracy of Prion Disease Biomarkers in Iatrogenic Creutzfeldt-Jakob Disease

Human prion diseases are classified into sporadic, genetic, and acquired forms. Within this last group, iatrogenic Creutzfeldt-Jakob disease (iCJD) is caused by human-to-human transmission through surgical and medical procedures. After reaching an incidence peak in the 1990s, it is believed that the iCJD historical period is probably coming to an end, thanks to lessons learnt from past infection sources that promoted new prion prevention and decontamination protocols. At this point, we sought to characterise the biomarker profile of iCJD and compare it to that of sporadic CJD (sCJD) for determining the value of available diagnostic tools in promptly recognising iCJD cases. To that end, we collected 23 iCJD samples from seven national CJD surveillance centres and analysed the electroencephalogram and neuroimaging data together with a panel of seven CSF biomarkers: 14-3-3, total tau, phosphorylated/total tau ratio, alpha-synuclein, neurofilament light, YKL-40, and real-time quaking induced conversion of prion protein. Using the cut-off values established for sCJD, we found the sensitivities of these biomarkers for iCJD to be similar to those described for sCJD. Given the limited relevant information on this issue to date, the present study validates the use of current sCJD biomarkers for the diagnosis of future iCJD cases.

Study protocol for enhanced CJD surveillance in the 65+ years population group in Scotland: an observational neuropathological screening study of banked brain tissue donations for evidence of prion disease

INTRODUCTION

Creutzfeldt-Jakob disease (CJD) is a human prion disease that occurs in sporadic, genetic and acquired forms. Variant CJD (vCJD) is an acquired form first identified in 1996 in the UK. To date, 178 cases of vCJD have been reported in the UK, most of which have been associated with dietary exposure to the bovine spongiform encephalopathy agent. Most vCJD cases have a young age of onset, with a median age at death of 28 years. In the UK, suspected cases of vCJD are reported to the UK National Creutzfeldt-Jakob Disease Research & Surveillance Unit (NCJDRSU). There is, however, a concern that the national surveillance system might be missing some cases of vCJD or other forms of human prion disease, particularly in the older population, perhaps because of atypical clinical presentation. This study aims to establish whether there is unrecognised prion disease in people aged 65 years and above in the Scottish population by screening banked brain tissue donated to the Edinburgh Brain Bank (EBB).

METHODS

Neuropathological screening of prospective and retrospective brain tissue samples is performed. This involves histopathological and immunohistochemical analysis and prion protein biochemical analysis. During the study, descriptive statistics are used to describe the study population, including the demographics and clinical, pathological and referral characteristics. Controlling for confounders, univariate and multivariate analyses will be used to compare select characteristics of newly identified suspect cases with previously confirmed cases referred to the NCJDRSU.

ETHICS AND DISSEMINATION

Brain tissue donations to EBB are made voluntarily by the relatives of patients, with consent for use in research. The EBB has ethical approval to provide tissue samples to research projects (REC reference 16/ES/0084). The findings of this study will be disseminated in meetings, conferences, workshops and as peer-reviewed publications.

TRIAL REGISTRATION NUMBERS

10/S1402/69 and 10/S1402/70.

A case of probable sporadic Creutzfeldt-Jacob Disease in a tertiary care hospital in Malaysia

The diagnosis of Creutzfeldt-Jakob disease (CJD) can be challenging as findings are non-specific and there is low awareness of the disease. We present a case of an 83-yearold man with a two months history of rapidly progressive dementia. After a series of extensive diagnostic examinations, he was diagnosed with probable sporadic CJD with key findings of rapidly progressive dementia, myoclonus, pyramidal signs, abnormal hyperintensity signals on diffusion-weighted magnetic resonance imaging (DW-MRI) and typical electroencephalograph (EEG). His symptoms progressively worsened and he died four months after the onset of symptoms.

Sporadic Creutzfeldt-Jakob disease

Sporadic Creutzfeldt-Jakob disease (CJD), the most common human prion disease, is generally regarded as a spontaneous neurodegenerative illness, arising either from a spontaneous PRNP somatic mutation or a stochastic PrP structural change. Alternatively, the possibility of an infection from animals or other source remains to be completely ruled out. Sporadic CJD is clinically characterized by rapidly progressive dementia with ataxia, myoclonus, or other neurologic signs and, neuropathologically, by the presence of aggregates of abnormal prion protein, spongiform change, neuronal loss, and gliosis. Despite these common features the disease shows a wide phenotypic variability which was recognized since its early descriptions. In the late 1990s the identification of key molecular determinants of phenotypic expression and the availability of a large series of neuropathologically verified cases led to the characterization of definite clinicopathologic and molecular disease subtypes and to an internationally recognized disease classification. By showing that these disease subtypes correspond to specific agent strain-host genotype combinations, recent transmission studies have confirmed the biologic basis of this classification. The introduction of brain magnetic resonance imaging techniques such as fluid-attenuated inversion recovery and diffusion-weighted imaging sequences and cerebrospinal fluid biomarker assays for the detection of brain-derived proteins as well as real-time quaking-induced conversion assay, allowing the specific detection of prions in accessible biologic fluids and tissues, has significantly contributed to the improved accuracy of the clinical diagnosis of sporadic CJD in recent years.

Post-mortem magnetic resonance imaging in patients with suspected prion disease: Pathological confirmation, sensitivity, specificity and observer reliability. A national registry

The relationship between magnetic resonance imaging (MRI) and clinical variables in patients suspected to have Creutzfeldt-Jakob Disease (CJD) is uncertain. We aimed to determine which MRI features of CJD (positive or negative), previously described in vivo, accurately identify CJD, are most reliably detected, vary with disease duration, and whether combined clinical and imaging features increase diagnostic accuracy for CJD. Prospective patients suspected of having CJD were referred to the National CJD Research and Surveillance Unit between 1994–2004; post-mortem, brains were sent for MRI and histopathology. Two neuroradiologists independently assessed MRI for atrophy, white matter hyperintensities, and caudate, lentiform and pulvinar signals, blind to histopathological diagnosis and clinical details. We examined differences in variable frequencies using Fisher’s exact tests, and associations between variables and CJD in logistic regression models. Amongst 200 cases, 118 (59%) with a histopathological diagnosis of CJD and 82 (41%) with histopathological diagnoses other than CJD, a logistic regression model including age, disease duration at death, atrophy, white matter hyperintensities, bright or possibly bright caudate, and present pulvinar sign correctly classified 81% of cases as CJD versus not CJD. Pulvinar sign alone was not independently associated with an increased likelihood of histopathologically-confirmed CJD (of any subtype) or sporadic CJD after adjustment for age at death, disease duration, atrophy, white matter hyperintensities or caudate signal; despite the large sample, data sparsity precluded investigation of the association of pulvinar sign with variant CJD. No imaging feature varied significantly with disease duration. Of the positive CJD signs, neuroradiologists most frequently agreed on the presence or absence of atrophy (agreements in 169/200 cases [84.5%]). Combining patient age, and disease duration, with absence of atrophy and white matter hyperintensities and presence of increased caudate signal and pulvinar sign predicts CJD with good accuracy. Autopsy remains essential.

Sporadic Creutzfeldt-Jakob Disease in 2 Plasma Product Recipients, United Kingdom

Sporadic Creutzfeldt-Jakob disease (sCJD) has not been previously reported in patients with clotting disorders treated with fractionated plasma products. We report 2 cases of sCJD identified in the United Kingdom in patients with a history of extended treatment for clotting disorders; 1 patient had hemophilia B and the other von Willebrand disease. Both patients had been informed previously that they were at increased risk for variant CJD because of past treatment with fractionated plasma products sourced in the United Kingdom. However, both cases had clinical and investigative features suggestive of sCJD. This diagnosis was confirmed in both cases on neuropathologic and biochemical analysis of the brain. A causal link between the treatment with plasma products and the development of sCJD has not been established, and the occurrence of these cases may simply reflect a chance event in the context of systematic surveillance for CJD in large populations.

Prion diseases with a focus on Creutzfeldt-Jakob disease, a summary of the incidence of Creutzfeldt-Jakob disease in the Czech Republic over the last 17 years, 2000-2017

BACKGROUND

Creutzfeldt-Jakob disease (CJD) is a prion disease. It is a rare, rapidly progressing fatal disorder of the central nervous system, which occurs in four forms: sporadic (sCJD), genetic/familial (gCJD), iatrogenic (iCJD), and variant (vCJD).

METHODS

CJD research in the Czech Republic (CR) is conducted by the National Reference Laboratory for Human Transmissible Spongiform Encephalopathies and Creutzfeldt-Jakob Disease, Department of Pathology and Molecular Medicine, established in 2001 at the Department of Pathology, Thomayer Hospital, Prague. In 2003, this NRL was included in the European network of laboratories monitoring prion diseases. The purpose of the article is to analyse data reported to the EPIDAT system.

RESULTS

From June 2000 to June 2017, 207 deaths in persons diagnosed with CJN and four suspected deaths due to gCJD were reported to the EPIDAT system (national program of reporting, recording, and analysis of data on transmissible diseases in the CR).

CONCLUSION

Reporting CJD cases to the EPIDAT is helpful in meeting the important goals, i.e. monitoring the incidence and trends of the disease. The incidence of gCJD in particular requires improved diagnosis based on a detailed personal and family history, and thorough epidemiological investigation is crucial to detect possible iatrogenic diseases.

Infectious and Sporadic Prion Diseases

Prion diseases are progressive fatal encephalopathies characterized by a neurodegenerative pathology, the tissue deposition of abnormally folded prion protein and, in general, potential transmissibility. Creutzfeldt-Jakob disease (CJD) is the commonest human prion disease and occurs in three principal forms: sporadic (idiopathic), acquired (infectious), and inherited (genetic). This chapter concerns the sporadic and acquired forms. Sporadic CJD occurs worldwide and affects mainly the middle aged and elderly. There are recognized genetic risk factors-most importantly the PRNP-129 polymorphism. The acquired forms of CJD consist of iatrogenic CJD (accidental transmission of CJD via medical or surgical procedures) and variant CJD (vJCD) (which originated as a zoonosis via bovine spongiform encephalopathy (BSE)-contamination of human food). The main causes of iatrogenic CJD are cadaveric-derived human growth hormone treatment and dura mater surgical grafts. The PRNP-129 polymorphism has important effects on iatrogenic infection, including overall susceptibility and incubation period. vCJD, resulting from dietary exposure to BSE, has affected mostly the United Kingdom, followed by France. All tested cases were originally PRNP-129MM, although two MV cases have been identified recently (one possible; one definite). vCJD has been secondarily transmitted via blood transfusion and a blood product. There is continuing concern over secondary transmission since there is evidence-from lymphoreticular tissue studies-of extensive subclinical infection in the UK general population, although a further recent study has caused uncertainty over the significance of the previous studies. While definitive diagnosis of CJD is pathological, recent developments in protein amplification and detection have led to significantly better clinical diagnosis.

A case cluster of variant Creutzfeldt-Jakob disease linked to the Kingdom of Saudi Arabia

As of mid-2016, 231 cases of variant Creutzfeldt-Jakob disease-the human form of a prion disease of cattle, bovine spongiform encephalopathy-have been reported from 12 countries. With few exceptions, the affected individuals had histories of extended residence in the UK or other Western European countries during the period (1980-96) of maximum global risk for human exposure to bovine spongiform encephalopathy. However, the possibility remains that other geographic foci of human infection exist, identification of which may help to foreshadow the future of the epidemic. We report results of a quantitative analysis of country-specific relative risks of infection for three individuals diagnosed with variant Creutzfeldt-Jakob disease in the USA and Canada. All were born and raised in Saudi Arabia, but had histories of residence and travel in other countries. To calculate country-specific relative probabilities of infection, we aligned each patient's life history with published estimates of probability distributions of incubation period and age at infection parameters from a UK cohort of 171 variant Creutzfeldt-Jakob disease cases. The distributions were then partitioned into probability density fractions according to time intervals of the patient's residence and travel history, and the density fractions were combined by country. This calculation was performed for incubation period alone, age at infection alone, and jointly for incubation and age at infection. Country-specific fractions were normalized either to the total density between the individual's dates of birth and symptom onset ('lifetime'), or to that between 1980 and 1996, for a total of six combinations of parameter and interval. The country-specific relative probability of infection for Saudi Arabia clearly ranked highest under each of the six combinations of parameter × interval for Patients 1 and 2, with values ranging from 0.572 to 0.998, respectively, for Patient 2 (age at infection × lifetime) and Patient 1 (joint incubation and age at infection × 1980-96). For Patient 3, relative probabilities for Saudi Arabia were not as distinct from those for other countries using the lifetime interval: 0.394, 0.360 and 0.378, respectively, for incubation period, age at infection and jointly for incubation and age at infection. However, for this patient Saudi Arabia clearly ranked highest within the 1980-96 period: 0.859, 0.871 and 0.865, respectively, for incubation period, age at infection and jointly for incubation and age at infection. These findings support the hypothesis that human infection with bovine spongiform encephalopathy occurred in Saudi Arabia.

Creutzfeldt-Jakob disease surveillance in Australia: update to December 2015

Nation-wide surveillance of human transmissible spongiform encephalopathies (also known as prion diseases), the most common being Creutzfeldt-Jakob disease, is performed by the Australian National Creutzfeldt-Jakob Disease Registry, based at the University of Melbourne. Prospective surveillance has been undertaken since 1993 and over this dynamic period in transmissible spongiform encephalopathy research and understanding, the unit has evolved and adapted to changes in surveillance practices and requirements concomitant with the delineation of new disease subtypes, improvements in diagnostic capabilities and the overall heightened awareness of prion diseases in the health care setting. In 2015, routine national surveillance continued and this brief report provides an update of the cumulative surveillance data collected by the Australian National Creutzfeldt-Jakob Disease Registry prospectively from 1993 to December 2015, and retrospectively to 1970.

Creutzfeldt-Jakob disease surveillance in Australia: update to December 2014

Nation-wide surveillance of human transmissible spongiform encephalopathies (also known as prion diseases), the most common being Creutzfeldt-Jakob disease, is performed by the Australian National Creutzfeldt-Jakob Disease Registry, based at the University of Melbourne. Prospective surveillance has been undertaken since 1993 and over this dynamic period in transmissible spongiform encephalopathy research and understanding, the unit has evolved and adapted to changes in surveillance practices and requirements concomitant with the emergence of new disease subtypes, improvements in diagnostic capabilities and the overall heightened awareness of prion diseases in the health care setting. In 2014, routine national surveillance continued and this brief report provides an update of the cumulative surveillance data collected by the Australian National Creutzfeldt-Jakob Disease Registry prospectively from 1993 to December 2014, and retrospectively to 1970.

Recent US Case of Variant Creutzfeldt-Jakob Disease-Global Implications

A recently diagnosed case highlights the need for continued global surveillance.

Variant Creutzfeldt-Jakob disease (vCJD) is a rare, fatal prion disease resulting from transmission to humans of the infectious agent of bovine spongiform encephalopathy. We describe the clinical presentation of a recent case of vCJD in the United States and provide an update on diagnostic testing. The location of this patient’s exposure is less clear than those in the 3 previously reported US cases, but strong evidence indicates that exposure to contaminated beef occurred outside the United States more than a decade before illness onset. This case exemplifies the persistent risk for vCJD acquired in unsuspected geographic locations and highlights the need for continued global surveillance and awareness to prevent further dissemination of vCJD.

The Features of Genetic Prion Diseases Based on Chinese Surveillance Program

Objective

To identify the features of Chinese genetic prion diseases.

Methods

Suspected Creutzfeldt-Jakob disease (CJD) cases that were reported under CJD surveillance were diagnosed and subtyped using the diagnostic criteria issued by the WHO. The general information concerning the patient, their clinical, MRI and EEG data, and the results of CSF 14-3-3 and PRNP sequencing were carefully collected from the database of the national CJD surveillance program and analyzed using the SPSS 11.5 statistical software program.

Results

Since 2006, 69 patients were diagnosed with genetic prion diseases and as having 15 different mutations. The median age of the 69 patients at disease onset was 53.5 years, varying from 19 to 80 years. The majority of patients displaying clinical symptoms were in the 50–59 years of age. FFI, T188K gCJD and E200K were the three most common subtypes. The disease appeared in the family histories of 43.48% of the patients. The clinical manifestations varied considerably among the various diseases. Patients who carried mutations in the N-terminus displayed a younger age of onset, were CSF 14-3-3 negative, had a family history of the condition, and experienced a longer duration of the condition. The clinical courses of T188K were significantly shorter than those of FFI and E200K gCJD, while the symptoms in the FFI group appeared at a younger age and for a longer duration. Moreover, the time intervals between the initial neurologist visit to the final diagnosis were similar among patients with FFI, T188K gCJD, E200K gCJD and other diseases.

Conclusion

The features of Chinese genetic prion diseases are different from those seen in Europe and other Asian countries.

[Human prion diseases in the Czech Republic]

Human prion diseases are a group of very rare diseases with a unique pathogenesis and, due to an inauspicious prognosis and unavailability of therapy, with fatal consequences. The etiopathogenetic background is the presence of pathologically misfolded prion protein, highly resistant to denaturation, the aggregation and presence of which in the brain tissue causes irreversible neuronal damage. The most frequent prion disease in humans is Creutzfeldt-Jakob disease (CJD) which occurs in sporadic, hereditary/familial, or acquired/infectious/iatrogenic forms. A new form of CJD, variant CJD, is considered to be linked to dietary exposure to beef products from cattle infected with bovine spongiform encephalopathy (BSE) and to infection via blood transfusion. The clinical picture of these diseases is characterized by a rapidly progressing dementia, cerebellar and extrapyramidal symptoms, and rather specific MRI, EEG, and CSF findings. Clinically, the diagnosis is described as possible or probable prion disease and needs to be confirmed by neuropathological or immunological investigation of the brain tissue. Epidemiological data from the Czech Republic spanning the last decade are presented.

[Phenotype and incidence of Creutzfeldt-Jakob disease in Finland in 1997-2013]

INTRODUCTION

The incidence of Creutzfeldt-Jakob disease (CJD) in Finland in 1974-1989 was reported to be 0.6/1 000 000. Our aim was to compare the current incidence of CJD in Finland with the earlier incidence and also study the diagnostics of the disease.

METHODS

Register study of the Finnish CJD cases from 1997 to 2012 and the clinical data of CJD patients within the Hospital District of Southwest Finland from 2007 to 2013.

RESULTS

There were 119 cases. The average yearly incidence was 1.36-1.44/1 000 000.

CONCLUSIONS

Compared with the previous study, the incidence in Finland appears to have increased. The change is propably due to increased awareness and improved diagnostic methods.

Creutzfeldt-Jakob disease surveillance in Australia, update to December 2013

Nation-wide surveillance of transmissible spongiform encephalopathies including Creutzfeldt-Jakob disease, is performed by the Australian National Creutzfeldt-Jakob Disease Registry, based at the University of Melbourne. Surveillance has been undertaken since 1993. Over this dynamic period in transmissible spongiform encephalopathy research and understanding, the unit has evolved and adapted to changes in surveillance practices and requirements, the emergence of new disease subtypes, improvements in diagnostic capabilities and the overall heightened awareness and understanding of Creutzfeldt-Jakob disease and other transmissible spongiform encephalopathies in the health care setting. In 2013, routine surveillance continued and this brief report provides an update of the surveillance data collected by the Australian National Creutzfeldt-Jakob Disease Registry prospectively from 1993 to December 2013, and retrospectively to 1970. The report highlights the recent multi-national collaborative study published that has verified the correlation between surveillance intensity and reported disease incidence.

Managing the risk of iatrogenic transmission of Creutzfeldt-Jakob disease in the UK

BACKGROUND

With the emergence of bovine spongiform encephalopathy (BSE) and variant Creutzfeldt-Jakob disease (CJD) in the UK, there is concern about iatrogenic transmission, and the approach to managing this risk is unique.

AIM

To describe and review CJD incident management and the notification of individuals 'at increased risk' as a strategy for reducing iatrogenic transmission.

METHODS

A description of iatrogenic CJD transmission, the CJD Incidents Panel's role, the number and nature of CJD incidents reported and the individuals considered 'at increased risk' by mid-2012.

FINDINGS

Seventy-seven UK cases of CJD are likely to have resulted from iatrogenic transmission, among recipients of human-derived growth hormone (64 cases), dura mater grafts (eight cases), blood transfusions (four cases) and plasma products (one case). To limit transmission, the Panel reviewed 490 incidents and advised on look-backs, recalls of blood and plasma products, and quarantining and disposing of surgical instruments. Additionally, on Panel advice, around 6000 asymptomatic individuals have been informed they are at increased risk of CJD and have been asked to follow public health precautions.

CONCLUSION

The strategy to reduce iatrogenic transmission of CJD has been developed in a context of scientific uncertainty. The rarity of transmission events could indicate that incident-related exposures present negligible transmission risks, or--given the prolonged incubation and subclinical phenotypes of CJD--infections could be yet to occur or have been undetected. Scientific developments, including better estimates of infection prevalence, a screening test, or improvements in decontaminating surgical instruments, may change future risk management.

Two cases of Creutzfeldt-Jakob disease from an ongoing dementia registry in Pakistan

Creutzfeldt-Jakob disease (CJD) is a rare prion disease that leads to a rapidly progressive dementia (RPD) and associated neurological features. It is not well documented in our country; therefore its true prevalence in Pakistan is not known. Here we report two cases of sporadic probable CJD seen in our hospital. The first, a 62 years old female, presented with RPD and myoclonus. The second was a 72 years old female who presented with generalized axial and limb rigidity, mutisim, personality changes and hallucinations along with RPD. Both cases were diagnosed as CJD on the basis of clinical, MRI and EEG findings.

Accuracy of administrative diagnostic data for pathologically confirmed cases of Creutzfeldt-Jakob disease in Massachusetts, 2000-2008

BACKGROUND

Creutzfeldt-Jakob disease (CJD) is a transmissible disorder that is monitored by public health authorities at the state and national levels in the United States. Little is known about the current accuracy and concurrence of CJD diagnoses across national and state sources of surveillance data.

METHODS

Using multiple sources, including the National Prion Disease Pathology Surveillance Center (NPDPSC) registry, we sought to identify all deceased Massachusetts patients with pathologically diagnosed CJD between 2000 and 2008. Pathologically verified CJD cases were then matched to their respective records in the Massachusetts hospital discharge and death certificate datasets. Using these data, we also aimed to estimate the sensitivity and specificity of death certificate diagnoses.

RESULTS

Death certificate and hospital discharge dataset diagnoses of CJD combined accounted for 80% (35 of 44) of pathologically confirmed cases. The estimated sensitivity and specificity for death certificate diagnoses alone were 71% (27 of 38) and 75% (9 of 12), respectively.

CONCLUSIONS

Death certificate diagnoses were less sensitive for pathologically confirmed CJD than reported previously. Increasing reliance on autopsy over biopsy and an expanding spectrum of health care delivery may be responsible for this discrepancy. The findings reported here underscore the value of using multiple mechanisms in national CJD surveillance.

Estimation of the exposure of the UK population to the bovine spongiform encephalopathy agent through dietary intake during the period 1980 to 1996

Although the incidence of variant Creutzfeldt-Jakob disease (vCJD) has declined to 1 since 2012 in the UK, uncertainty remains regarding possible future cases and the size of the subclinical population that may cause secondary transmission of the disease through blood transfusion. Estimating the number of individuals who were exposed to the bovine spongiform encephalopathy (BSE) infectious agent and may be susceptible to vCJD will help to clarify related public health concerns and plan strategies. In this paper, we explore this estimate by describing the probability of potential exposure due to dietary intake throughout the BSE epidemic period from 1980 to 1996 as a stochastic Poisson process. We estimate the age- and gender-specific exposure intensities in food categories of beef and beef-containing dishes, burgers and kebabs, pies, and sausages, separating the two periods of 1980-1989 and 1990-1996 due to the specified bovine offal legislation of 1989. The estimated total number of (living) exposed individuals during each period is 5,089,027 (95% confidence interval [CI] 4,514,963-6,410,317), which was obtained by multiplying the population size of different birth cohorts by the probability of exposure via dietary intake and the probability of survival until the end of 2013. The estimated number is approximately doubled, assuming a contamination rate of [Formula: see text]. Among those individuals estimated, 31,855 (95% CI 26,849-42,541) are susceptible to infection. We also examined the threshold hypothesis by fitting an extreme-value distribution to the estimated infectious dose of the exposed individuals and obtained a threshold estimate of 13.7 bID50 (95% CI 6.6-26.2 bID50) (Weibull). The results provide useful information on potential carriers of prion disease who may pose a threat of infection via blood transfusion and thus provide insight into the likelihood of new incidents of vCJD occurring in the future.

Population screening for variant Creutzfeldt-Jakob disease using a novel blood test: diagnostic accuracy and feasibility study

IMPORTANCE

Our study indicates a prototype blood-based variant Creutzfeldt-Jakob disease (vCJD) assay has sufficient sensitivity and specificity to justify a large study comparing vCJD prevalence in the United Kingdom with a bovine spongiform encephalopathy-unexposed population. In a clinical diagnostic capacity, the assay's likelihood ratios dramatically change an individual's pretest disease odds to posttest probabilities and can confirm vCJD infection.

OBJECTIVES

To determine the diagnostic accuracy of a prototype blood test for vCJD and hence its suitability for clinical use and for screening prion-exposed populations.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective, cross-sectional diagnostic study of blood samples from national blood collection and prion disease centers in the United States and United Kingdom. Anonymized samples were representative of the US blood donor population (n = 5000), healthy UK donors (n = 200), patients with nonprion neurodegenerative diseases (n = 352), patients in whom a prion disease diagnosis was likely (n = 105), and patients with confirmed vCJD (n = 10).

MAIN OUTCOME AND MEASURE

Presence of vCJD infection determined by a prototype test (now in clinical diagnostic use) that captures, enriches, and detects disease-associated prion protein from whole blood using stainless steel powder.

RESULTS

The assay's specificity among the presumed negative American donor samples was 100% (95% CI, 99.93%-100%) and was confirmed in a healthy UK cohort (100% specificity; 95% CI, 98.2%-100%). Of potentially cross-reactive blood samples from patients with nonprion neurodegenerative diseases, no samples tested positive (100% specificity; 95% CI, 98.9%-100%). Among National Prion Clinic referrals in whom a prion disease diagnosis was likely, 2 patients with sporadic CJD tested positive (98.1% specificity; 95% CI, 93.3%-99.8%). Finally, we reconfirmed but could not refine our previous sensitivity estimate in a small blind panel of samples from unaffected individuals and patients with vCJD (70% sensitivity; 95% CI, 34.8%-93.3%).

CONCLUSIONS AND RELEVANCE

In conjunction with the assay's established high sensitivity (71.4%; 95% CI, 47.8%-88.7%), the extremely high specificity supports using the assay to screen for vCJD infection in prion-exposed populations. Additionally, the lack of cross-reactivity and false positives in a range of nonprion neurodegenerative diseases supports the use of the assay in patient diagnosis.