1
|
Pozzo di Borgo A, Rochette S, Gaussen A, O'Brien SF, Germain M, Renaud C, Lewin A. Transmission of Variant Creutzfeldt-Jakob Disease Through Blood Transfusion and Plasma-Derived Products: A Narrative Review of Observed and Modeled Risks. Transfus Med Rev 2023; 37:150747. [PMID: 37827587 DOI: 10.1016/j.tmrv.2023.150747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2023] [Revised: 05/13/2023] [Accepted: 05/15/2023] [Indexed: 10/14/2023]
Abstract
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 However, published reviews on this topic are outdated, focused on a single country or product type, or did not comprehensively review modeling studies on the risk of transfusion-transmission.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.
Collapse
Affiliation(s)
| | - Samuel Rochette
- Medical Affairs and Innovation, Héma-Québec, Montreal, Quebec, Canada.
| | - Amaury Gaussen
- Medical Affairs and Innovation, Héma-Québec, Quebec, Quebec, Canada.
| | - Sheila F O'Brien
- Epidemiology and Surveillance, Canadian Blood Services, Ottawa, Ontario, Canada.
| | - Marc Germain
- Medical Affairs and Innovation, Héma-Québec, Quebec, Quebec, Canada.
| | - Christian Renaud
- Medical Affairs and Innovation, Héma-Québec, Montreal, Quebec, Canada.
| | - Antoine Lewin
- Medical Affairs and Innovation, Héma-Québec, Montreal, Quebec, Canada.
| |
Collapse
|
2
|
Abstract
Advances in the development of effective and safe treatments for haemophilia over the last 50 years have resulted in a significant increase in the life expectancy of persons with haemophilia (PWH). The management of this new cohort of middle-aged and elderly PWH is challenging because of the opposing risks of haemophilia and age-related cardiovascular disease and malignancy. Furthermore, this cohort of ageing PWH has the additional comorbidities of human immunodeficiency virus/hepatitis C and chronic haemophilic arthropathy. This article reviews the prevalence, underlying mechanisms and treatment strategies for managing these comorbidities. International collaboration is essential for registry data and further prospective trials to inform optimal evidence-based management for this rare disorder in the future.
Collapse
Affiliation(s)
- Susan Shapiro
- Oxford Haemophilia and Thrombosis Centre, NIHR Oxford Biomedical Research Centre, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Mike Makris
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, UK.,Sheffield Haemophilia and Thrombosis Centre, Royal Hallamshire Hospital, Sheffield, UK
| |
Collapse
|
3
|
Ward H, Molesworth A, Holmes S, Sinka K. Public health: surveillance, infection prevention, and control. HANDBOOK OF CLINICAL NEUROLOGY 2018; 153:473-484. [PMID: 29887154 DOI: 10.1016/b978-0-444-63945-5.00027-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Human prion diseases, though relatively rare, remain an ongoing public health problem. They are fatal diseases, with unconventional host responses and no early diagnostic tests or robust treatments. Public health measures were put in place to protect the food chain in the United Kingdom from the late 1980s, with similar measures following elsewhere. However, human prion diseases are transmissible through other routes, including through blood transfusion and surgery. As a result, the public health threat remains for all forms of human prion diseases and makes continued surveillance and infection prevention and control imperative.
Collapse
Affiliation(s)
- Hester Ward
- NHS National Services Scotland, Edinburgh, United Kingdom; Usher Institute of Population Health Sciences and Informatics, University of Edinburgh, Edinburgh, United Kingdom.
| | - Anna Molesworth
- National CJD Research and Surveillance Unit, Western General Hospital, Edinburgh, United Kingdom
| | - Sulisti Holmes
- NHS National Services Scotland, Edinburgh, United Kingdom
| | - Katy Sinka
- Centre for Infectious Disease Surveillance and Control, National Infection Service, Public Health England, London, United Kingdom
| |
Collapse
|
4
|
Franchini M, Mannucci PM. The safety of pharmacologic options for the treatment of persons with hemophilia. Expert Opin Drug Saf 2016; 15:1391-400. [DOI: 10.1080/14740338.2016.1208747] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Massimo Franchini
- Department of Transfusion Medicine and Hematology, Carlo Poma Hospital, Mantova, Italy
| | - Pier Mannuccio Mannucci
- Angelo Bianchi Bonomi Hemophilia and Thrombosis Center, Fondazione IRCCS Ca’ Granda-Ospedale Maggiore Policlinico and University of Milan, Milan, Italy
| |
Collapse
|
5
|
Abstract
The introduction of clotting factor concentrates has transformed the lives of persons with inherited bleeding disorders. With the use of prophylactic treatment, it is now possible to prevent bleeding in these individuals. The early concentrates were contaminated with the HIV and hepatitis C viruses (HCV) and resulted in major morbidity and mortality in the recipients. Current products are much safer, especially in terms of infectious agents, but other adverse events such as alloantibodies (inhibitors), allergic reactions and thrombotic risks remain of concern. Approximately 30% of previously untreated patients with severe haemophilia A develop inhibitors, making this the most important issue in haemophilia care today. Recently, it was suggested that one of the most commonly used concentrates was associated with a higher inhibitor risk, but this was not supported by the evidence from all studies. Good safety surveillance systems are essential for all diseases and products but are particularly so in the group of individuals with inherited bleeding disorders treated with clotting factor concentrates who have suffered disproportionately from the adverse effects of their treatment. National and multinational systems are now in place to allow reporting of adverse events in patients with inherited bleeding disorders. All clinicians treating individuals with inherited bleeding disorders should prospectively report adverse events to treatment even if they are believed to be common and well recognized.
Collapse
Affiliation(s)
- R Lassila
- Helsinki University Hospital, Coagulation Disorders, Hematology and Comprehensive Cancer Center, University of Helsinki, Helsinki, Finland
| | - M Makris
- Department of Cardiovascular Science, Medical School, University of Sheffield, Sheffield, UK.,Sheffield Haemophilia and Thrombosis Centre, Royal Hallamshire Hospital, Sheffield, UK
| |
Collapse
|
6
|
Maladies hémorragiques congénitales : quel avenir pour les dérivés plasmatiques par rapport aux recombinants et aux produits sanguins labiles ? Transfus Clin Biol 2015; 22:85-9. [DOI: 10.1016/j.tracli.2015.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2014] [Indexed: 11/21/2022]
|
7
|
Principles of treatment and update of recommendations for the management of haemophilia and congenital bleeding disorders in Italy. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2015; 12:575-98. [PMID: 25350962 DOI: 10.2450/2014.0223-14] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
8
|
Aouba A, Harroche A, Frenzel L, Torchet MF, Rothschild C, François I, Mamzer-Bruneel MF. Batch recall of French plasma-derived products due to variant Creutzfeldt-Jakob disease risk: the psychological impact on haemophilic patients, changes in their therapeutic demands and behaviour and ethical considerations. Haemophilia 2014; 21:27-33. [DOI: 10.1111/hae.12515] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/07/2014] [Indexed: 11/28/2022]
Affiliation(s)
- A. Aouba
- Center for Haemophilia Care and Department of Haematology; Hôpital Necker Enfants-Malades; Université Paris-Descartes; Assistance Publique-Hôpitaux de Paris; Paris France
- Medical Ethics Department EA 4569; Université Paris-Descartes; PRES Sorbonne-Paris-Cité Paris France
| | - A. Harroche
- Center for Haemophilia Care and Department of Haematology; Hôpital Necker Enfants-Malades; Université Paris-Descartes; Assistance Publique-Hôpitaux de Paris; Paris France
| | - L. Frenzel
- Center for Haemophilia Care and Department of Haematology; Hôpital Necker Enfants-Malades; Université Paris-Descartes; Assistance Publique-Hôpitaux de Paris; Paris France
| | - M. -F. Torchet
- Center for Haemophilia Care and Department of Haematology; Hôpital Necker Enfants-Malades; Université Paris-Descartes; Assistance Publique-Hôpitaux de Paris; Paris France
| | - C. Rothschild
- Center for Haemophilia Care and Department of Haematology; Hôpital Necker Enfants-Malades; Université Paris-Descartes; Assistance Publique-Hôpitaux de Paris; Paris France
| | - I. François
- Medical Ethics Department EA 4569; Université Paris-Descartes; PRES Sorbonne-Paris-Cité Paris France
| | - M. -F. Mamzer-Bruneel
- Medical Ethics Department EA 4569; Université Paris-Descartes; PRES Sorbonne-Paris-Cité Paris France
| |
Collapse
|
9
|
Dolan G, Makris M, Bolton-Maggs PHB, Rowell JA. Enhancing haemophilia care through registries. Haemophilia 2014; 20 Suppl 4:121-9. [PMID: 24762287 DOI: 10.1111/hae.12406] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/24/2014] [Indexed: 11/29/2022]
Abstract
Clinical registries or databases have an increasing role in the management of inherited bleeding disorders. Initially, research-based registries provided valuable data and now national databases are increasingly being developed with multiple stakeholders, including persons with haemophilia (PWH) and payers, to enable improvements and efficiencies in care. Registries are extending to international collaborations to collect adverse event data and comparisons of national approaches to the management of haemophilia to improve the availability of product to PWH.
Collapse
Affiliation(s)
- G Dolan
- Nottingham University Hospitals, Nottingham, UK
| | | | | | | |
Collapse
|
10
|
Bellon A, Comoy E, Simoneau S, Mornac S, Dehen C, Perrin A, Arzel A, Arrabal S, Baron H, Laude H, You B, Deslys JP, Flan B. Decontamination of prions in a plasma product manufacturing environment. Transfusion 2014; 54:1028-36. [PMID: 24032663 DOI: 10.1111/trf.12381] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2013] [Revised: 07/08/2013] [Accepted: 07/09/2013] [Indexed: 12/12/2022]
Abstract
BACKGROUND The high resistance of prions to inactivating treatments requires the proper management of decontaminating procedures of equipment in contact with materials of human or animal origin destined for medical purposes. Sodium hydroxide (NaOH) is widely used today for this purpose as it inactivates a wide variety of pathogens including prions. STUDY DESIGN AND METHODS Several NaOH treatments were tested on prions bound to either stainless steel or chromatographic resins in industrial conditions with multiple prion strains. RESULTS Data show a strong correlation between inactivation results obtained by immunochemical detection of the prion protein and those obtained with infectivity assays and establish effective inactivation treatments for prions bound to stainless steel or chromatographic resins (ion exchange and affinity), including treatments with lower NaOH concentrations. Furthermore, no obvious strain-specific behavior difference was observed between experimental models. CONCLUSION The results generated by these investigations show that industrial NaOH decontamination regimens (in combination with the NaCl elution in the case of the chromatography process) attain substantial prion inactivation and/or removal between batches, thus providing added assurance to the biologic safety of the final plasma-derived medicinal products.
Collapse
|
11
|
Liras A, García-Trenchard R. Treatment for hemophilia: recombinant versus plasma-derived coagulation factors - controversy and debate forever? An ethical medical challenge? Expert Rev Hematol 2013; 6:489-92. [PMID: 24083561 DOI: 10.1586/17474086.2013.834798] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- Antonio Liras
- Department of Physiology, Biological Sciences School, Complutense University of Madrid, Cell Therapy and Regenerative Medicine Unit, La Paz University Hospital Health Research Institute-IdiPAZ, Madrid, 28040, Spain
| | | |
Collapse
|
12
|
Foster PR. Plasma products and prion removal: “ Is you is or is you ain't …?”. Transfusion 2013; 53:1873-5. [DOI: 10.1111/trf.12301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
13
|
Martin M, Trouvin JH. Risk of transmission of Creutzfeldt-Jakob disease via blood and blood products. The French risk-analysis over the last 15 years. Transfus Clin Biol 2013; 20:398-404. [PMID: 23910008 DOI: 10.1016/j.tracli.2013.06.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2012] [Accepted: 06/25/2013] [Indexed: 11/28/2022]
Abstract
Risk of transmission of Creutzfeldt-Jakob disease (infectious agent, responsible of spongiform encephalopathy) via blood and blood components (including the plasma-derived medicinal products such as coagulation factors and immunoglobulins) have been a subject of concern for Health authorities since the early 1980s, with a regain of interest in the 1990s, with the bovine spongiform encephalopathy outbreak followed few years after with the notification of the first cases of variant Creutzfeldt-Jakob disease in humans. The risk-analysis and measures taken by the French authorities in the period 1990-2010 will be described with the various assumptions and working hypothesis used and revisited as new findings become available.
Collapse
Affiliation(s)
- M Martin
- French Agency for safety of medicines and health products (ANSM), 143, boulevard Anatole-France, 93285 Saint-Denis, France.
| | | |
Collapse
|
14
|
Ahmad J, Benson GM, McNulty OM, Burnside N, Gull S, Tailor IK, Winter PC, Spence RA. Surgeon and haematologist: A review of comprehensive care for patients with inherited bleeding disorders in Northern Ireland. Int J Surg 2013; 11:22-6. [DOI: 10.1016/j.ijsu.2012.12.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2012] [Revised: 12/07/2012] [Accepted: 12/07/2012] [Indexed: 12/31/2022]
|
15
|
Advanced therapies for the treatment of hemophilia: future perspectives. Orphanet J Rare Dis 2012; 7:97. [PMID: 23237078 PMCID: PMC3551751 DOI: 10.1186/1750-1172-7-97] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2012] [Accepted: 12/07/2012] [Indexed: 11/24/2022] Open
Abstract
Monogenic diseases are ideal candidates for treatment by the emerging advanced therapies, which are capable of correcting alterations in protein expression that result from genetic mutation. In hemophilia A and B such alterations affect the activity of coagulation factors VIII and IX, respectively, and are responsible for the development of the disease. Advanced therapies may involve the replacement of a deficient gene by a healthy gene so that it generates a certain functional, structural or transport protein (gene therapy); the incorporation of a full array of healthy genes and proteins through perfusion or transplantation of healthy cells (cell therapy); or tissue transplantation and formation of healthy organs (tissue engineering). For their part, induced pluripotent stem cells have recently been shown to also play a significant role in the fields of cell therapy and tissue engineering. Hemophilia is optimally suited for advanced therapies owing to the fact that, as a monogenic condition, it does not require very high expression levels of a coagulation factor to reach moderate disease status. As a result, significant progress has been possible with respect to these kinds of strategies, especially in the fields of gene therapy (by using viral and non-viral vectors) and cell therapy (by means of several types of target cells). Thus, although still considered a rare disorder, hemophilia is now recognized as a condition amenable to gene therapy, which can be administered in the form of lentiviral and adeno-associated vectors applied to adult stem cells, autologous fibroblasts, platelets and hematopoietic stem cells; by means of non-viral vectors; or through the repair of mutations by chimeric oligonucleotides. In hemophilia, cell therapy approaches have been based mainly on transplantation of healthy cells (adult stem cells or induced pluripotent cell-derived progenitor cells) in order to restore alterations in coagulation factor expression.
Collapse
|
16
|
Roberts PL, Dalton J, Evans D, Harrison P, Li Z, Ternouth K, Thirunavukkarasu V, Bulmer M, Fernando S, McLeod N. Removal of TSE agent from plasma products manufactured in the United Kingdom. Vox Sang 2012; 104:299-308. [PMID: 23170907 DOI: 10.1111/vox.12004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND AND OBJECTIVES The outbreak of vCJD in the UK leads to concern regarding the potential for human-to-human transmission of this agent. Plasma-derived products such as albumin, immunoglobulin and coagulation factors were manufactured by BPL from UK plasma up until 1999 when a switch to US plasma was made. In the current study, the capacity of various manufacturing processes that were in use both prior to and after this time to remove the TSE agent was tested. MATERIALS AND METHODS Small-scale models of the various product manufacturing steps were developed. Intermediates were spiked with scrapie brain extract and then further processed. Samples were assayed for the abnormal form of prion protein (PrP(SC) ) by Western blotting, and the reduction in the amount of scrapie agent determined. RESULTS Many of the manufacturing process steps produced significant reduction in the scrapie agent. Particularly effective were steps such as ethanol fractionation, depth filtration, ion-exchange and copper chelate affinity chromatography. Virus retentive filters, of nominal pore size 15 or 20 nm, removed >3 log. The total cumulative reduction capacity for individual products was estimated to range from 7 to 14 log. In the case of factor VIII (8Y), the total removal was limited to 3 log. CONCLUSION All the processes showed a substantial capacity to remove the TSE agent. However, this was more limited for the intermediate purity factor VIII 8Y which included fewer manufacturing steps.
Collapse
Affiliation(s)
- P L Roberts
- Bio Products Laboratory Ltd, Elstree, Herts, UK.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
17
|
Casademunt E, Martinelle K, Jernberg M, Winge S, Tiemeyer M, Biesert L, Knaub S, Walter O, Schröder C. The first recombinant human coagulation factor VIII of human origin: human cell line and manufacturing characteristics. Eur J Haematol 2012; 89:165-76. [PMID: 22690791 PMCID: PMC3443369 DOI: 10.1111/j.1600-0609.2012.01804.x] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/09/2012] [Indexed: 01/02/2023]
Abstract
INTRODUCTION Since the early 1990s, recombinant human clotting factor VIII (rhFVIII) produced in hamster cells has been available for haemophilia A treatment. However, the post-translational modifications of these proteins are not identical to those of native human FVIII, which may lead to immunogenic reactions and the development of inhibitors against rhFVIII. For the first time, rhFVIII produced in a human host cell line is available. AIM We describe here the establishment of the first human production cell line for rhFVIII and the manufacturing process of this novel product. METHODS AND RESULTS A human cell line expressing rhFVIII was derived from human embryonic kidney (HEK) 293 F cells transfected with an FVIII expression plasmid. No virus or virus-like particles could be detected following extensive testing. The stringently controlled production process is completely free from added materials of animal or human origin. Multistep purification employing a combination of filtration and chromatography steps ensures the efficient removal of impurities. Solvent/detergent treatment and a 20 nm pore size nanofiltration step, used for the first time in rhFVIII manufacturing, efficiently eliminate any hypothetically present viruses. In contrast to hamster cell-derived products, this rhFVIII product does not contain hamster-like epitopes, which might be expected to be immunogenic. CONCLUSIONS HEK 293 F cells, whose parental cell line HEK 293 has been used by researchers for decades, are a suitable production cell line for rhFVIII and will help avoid immunogenic epitopes. A modern manufacturing process has been developed to ensure the highest level of purity and pathogen safety.
Collapse
|
18
|
Millar CM, Makris M. Dealing with the uncertain risk of variant Creutzfeldt-Jakob disease transmission by coagulation replacement products. Br J Haematol 2012; 158:442-52. [DOI: 10.1111/j.1365-2141.2012.09201.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
| | - Mike Makris
- Department of Haematology; Sheffield Haemophilia and Thrombosis Centre; Sheffield; UK
| |
Collapse
|
19
|
de Pedro Cuesta J, Ruiz Tovar M, Ward H, Calero M, Smith A, Verduras CA, Pocchiari M, Turner ML, Forland F, Palm D, Will RG. Sensitivity to biases of case-control studies on medical procedures, particularly surgery and blood transfusion, and risk of Creutzfeldt-Jakob disease. Neuroepidemiology 2012; 39:1-18. [PMID: 22777385 DOI: 10.1159/000339318] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2011] [Accepted: 04/26/2012] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Evidence of risk of Creutzfeldt-Jakob disease (CJD) associated with medical procedures, including surgery and blood transfusion, is limited by susceptibility to bias in epidemiological studies. METHODS Sensitivity to bias was explored using a central-birth-cohort model using data from 18 case-control studies obtained after a review of 494 reports on medical procedures and risk of CJD, systematic for the period January 1, 1989 to December 31, 2011. RESULTS The validity of the findings in these studies may have been undermined by: recall; control selection; exposure assessment in life-time periods of different duration, out of time-at-risk of effect, or asymmetry in case/control data; and confounding by concomitant blood transfusion at the time of surgery. For sporadic CJD (sCJD), a history of surgery or blood transfusion was associated with risk in some, but not all, recent studies at a ≥10 year lag time, when controls were longitudinally sampled. Space-time aggregation of surgical events was not seen. Surgery at early clinical onset might be overrepresented among cases. Neither surgical history nor blood transfusion unlabelled for donor status, dental treatments or endoscopic examinations were linked to variant CJD (vCJD). CONCLUSIONS These results indicate the need for further research. Common challenges within these studies include access to and content of past medical/dental treatment records for diseases with long incubation periods.
Collapse
Affiliation(s)
- Jesús de Pedro Cuesta
- Department of Applied Epidemiology, National Centre for Epidemiology and Consortium for Biomedical Research in Neurodegenerative Diseases, Carlos III Institute of Health, Madrid, Spain.
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
20
|
Wisniewski T, Goñi F. Could immunomodulation be used to prevent prion diseases? Expert Rev Anti Infect Ther 2012; 10:307-17. [PMID: 22397565 DOI: 10.1586/eri.11.177] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
All prion diseases are currently without effective treatment and are universally fatal. The underlying pathogenesis of prion diseases (prionoses) is related to an autocatalytic conformational conversion of PrP(C) (C for cellular) to a pathological and infectious conformer known as PrP(Sc) (Sc for scrapie) or PrP(Res) (Res for proteinase K resistant). The past experience with variant Creutzfeldt-Jakob disease, which originated from bovine spongiform encephalopathy, as well as the ongoing epidemic of chronic wasting disease has highlighted the necessity for effective prophylactic and/or therapeutic approaches. Human prionoses are most commonly sporadic, and hence therapy is primarily directed to stop progression; however, in animals the majority of prionoses are infectious and, as a result, the emphasis is on prevention of transmission. These infectious prionoses are most commonly acquired via the alimentary tract as a major portal of infectious agent entry, making mucosal immunization a potentially attractive method to produce a local immune response that can partially or completely prevent prion entry across the gut barrier, while at the same time producing a modulated systemic immunity that is unlikely to be associated with toxicity. A critical factor in any immunomodulatory methodology that targets a self-antigen is the need to delicately balance an effective humoral immune response with potential autoimmune inflammatory toxicity. The ongoing epidemic of chronic wasting disease affecting the USA and Korea, with the potential to spread to human populations, highlights the need for such immunomodulatory approaches.
Collapse
Affiliation(s)
- Thomas Wisniewski
- New York University School of Medicine, 560 First Avenue, New York, NY 10016, USA.
| | | |
Collapse
|