HPA - Study results are consistent with earlier estimates of vCJD prion prevalence in Britain
The Health Protection Agency (HPA) and the UCL Institute of Neurology have conducted a sensitive examination of tonsil specimens to detect the presence of the variant Creutzfeldt-Jakob Disease (vCJD) related prion protein, and found results that are consistent with earlier estimates of vCJD prion prevalence in Britain. The findings are published today in The Journal of Pathology.
This study involved using immunohistochemistry to examine 9,160 anonymised tonsils for the presence of abnormal prions and found one sample showing evidence of prions associated with vCJD.
Study author Dr Jonathan Clewley, a HPA expert on vCJD, said: "We have used a sensitive test and the result is consistent with findings of earlier studies.
"The HPA will continue its research alongside the UCL Institute of Neurology and the Veterinary Laboratories Agency, to look at appendices by immunohistochemistry, in order to give greater confidence and accuracy to prevalence estimates of vCJD prions."
The anonymised tonsils used in this study were obtained from earlier studies - they had been removed from patients for clinical reasons and would otherwise have been discarded. Tonsils are one of a number of body tissues known to harbour abnormal prions in people who carry vCJD - other tissues where these prions can be found include the appendix.
Lead author Professor Sebastian Brandner, from the UCL Institute of Neurology, said: "Prevalence studies such as this are vitally important as they enable us to estimate the prevalence of vCJD in the population. However, it is important to understand that we do not know how good these tests are at picking up infected individuals and so the results may be an underestimate.
"They also give an indication as to the number of cases to expect in the future and the potential impact for the health service. Prion diseases can have long incubation periods, and an understanding of prevalence can help researchers devise measures to prevent further transmission of the disease."
There have been 220 clinically confirmed cases of vCJD worldwide, with the UK being most affected with 173 people having developed the disease, as a result of the epidemic of bovine spongiform encephalopathy in cattle in the 1980s. Large scale vCJD prion prevalence studies are challenging at present as there is no valid test available to screen for the vCJD prion in blood.
Notes to editors
1) The findings were published in The Journal of Pathology, in a paper entitled 'Large scale immunohistochemical examination for lymphoreticular prion protein in tonsil specimens collected in Britain', Fernandez de Marco, Linehan J, Gill O, Clewley J, Brandner S. The Journal of Pathology 2010; 222: DOI: 10.1002/path.2767.
2) 'The Journal of Pathology, published by John Wiley & Sons Ltd on behalf of the Pathological Society, can be accessed online at: www.thejournalofpathology.com. To access this article free of charge visit: http://dx.doi.org/10.1002/path.2767
3) The tonsil study used anonymised tonsils from patients in the 1961 to 1985 birth cohort.
4) Previous prevalence studies have included a 2004 study on appendices: Hilton DA, Ghani AC, Conyers L et al 'Prevalence of lymphoreticular prion protein accumulation in UK tissue samples'. The Journal of Pathology 2004; 203: 733-739, and a 2009 study by the Health Protection Agency which involved testing 63,007 tonsils - 'Prevalence of disease related prion protein in anonymous tonsil specimens in Britain: cross sectional opportunistic survey'. British Medical Journal; 338: 1442-1448
5) For more information or for media enquiries only please telephone the HPA press office on:
Kathryn Swan 020 8327 7097 Louise Brown 020 8327 7080 Eleanor Bunch 020 8327 7751 Georgina Fletcher 020 8327 6690 Emma Gilgunn Jones 020 8327 6647
http://www.wired-gov.net/wg/wg-news-1.nsf/lfi/DNWA-89XJ6J
Large-scale immunohistochemical examination for lymphoreticular prion protein in tonsil specimens collected in Britain†
Mar Fernandez de Marco1, Jacqueline Linehan2, O Noel Gill3, Jonathan P Clewley3,*, Sebastian Brandner1,*Article first published online: 4 OCT 2010
DOI: 10.1002/path.2767
Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Keywords:variant Creutzfeldt–Jakob disease;bovine spongiform encephalopathy;vCJD prevalence;PrP
ABSTRACT
There have been 173 cases of variant Creutzfeldt–Jakob disease (vCJD) in the UK, as of 5 July 2010, as a result of the bovine spongiform encephalopathy epidemic. The number of individuals subclinically infected with vCJD, and thus the eventual number of cases, remains, however, uncertain. In an attempt to address this problem, 63 007 tonsil tissue specimens were previously tested by enzyme immunoassay (EIA) for the presence of disease-related prion protein (PrPres) and found to be negative. To confirm the reliability of this result, all those in the birth cohort most at risk (1961–1985) and a few others, including controls, have now been tested by immunohistochemistry (IHC). Histological slides were prepared from 10 075 anonymized formalin-fixed, paraffin-embedded tissues and examined for PrPres with two anti-prion protein antibodies, ICMS35 and KG9. One specimen showed a single strongly positive follicle with both antibodies, on two slides from adjacent sections. As this specimen was negative when it was further investigated by EIA, IHC, and immunoblotting, it is unclear whether the patient from whom the tonsil came will go on to develop vCJD. If, however, this is the case, then a finding of 1 out of 9160 gives a prevalence of disease-related prion protein in the British population of 109 per million, with a 95% confidence interval (CI) of 3–608 per million, which is not statistically different (exact p = 0.63) from population prevalence estimates based on finding three positives out of 10 278 in a previous IHC study of appendix tissue. If this is not the case, a finding of 0 out of 9160 gives a prevalence of 0–403 per million (95% CI) for the 1961-1985 cohort, which is also not different (exact p = 0.25) from previous population prevalence estimates. Therefore, the results of this work could be summarized as finding, by IHC, no or one vCJD-positive individual.
Copyright © 2010 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
snip...
Discussion
Of the 9675 samples for which an IHC result was obtained, 9160 were in the 1961–1985 birth cohort. The remainder of the samples were selected for IHC because they showed some reactivity in the original serological screening of the 63 007 tonsils by EIA with Bio-Rad and Microsens kits 6. In addition, there were three positive controls (sheep scrapie) among the 9675 samples submitted for IHC. Three samples (18 864, 38 660, and 40 751) gave IHC results that needed to be investigated more fully. Two of these IHC results were concluded to be background staining by three experts, while for the third it was concluded that there was one strongly positive follicle with both KG9 and ICSM35 antibodies. This could not be confirmed by analysis of slides made from further tissue samples embedded in wax, neither could it be confirmed by IB. This result raises the question of the significance and interpretation of a single positive follicle among the thousands from several sections that were examined, particularly in the light of the failure of IB to confirm the presence of PrPCJD in the tissue. Further investigation of tissue from this specimen by bioassay or protein misfolding cyclic amplification (PMCA) was considered not to be worthwhile because bioassay is unlikely to be more sensitive than enhanced chemiluminescent IB tests 11, 25, 27, 28 and PMCA is insufficiently robust 29.
Our finding of one PrPres-positive follicle by IHC can be interpreted as showing that there is one individual in the 9160 samples from the 1961–1985 birth cohort who will go on to develop vCJD. Alternatively, if a single positive follicle is indicative of an insufficient amount of PrPres to spread and cause disease, the interpretation is that there is no one in the 9160 samples from the 1961–1985 birth cohort who will go on to develop vCJD. The decision between these two interpretations needs to be considered in the context of the relative sensitivities of the different tests that were used, and also in the context of the pathological significance of a small quantity of PrPres in a tonsil. Although all three methods (EIA, IB, and IHC) are based on the recognition of PrPres by specific anti-PrP antibodies, they are qualitatively and quantitatively different. As just a few stained cells can be seen by IHC, it could be argued that it is the more sensitive technique. Conversely, however, as a greater volume of tissue and therefore a larger number of cells can be tested by EIA and IB, it can be argued that they are the more sensitive methods 15. However, the distribution of PrPres in the tissue is likely to be an important factor in assessing the comparative sensitivities of different tests: when there is a very focal deposition of PrPres, IHC may be assumed to have the advantage.
Therefore, while we cannot say whether the patient from whom this tissue came will go on to develop vCJD, we can be reasonably certain, however, that the patient has not yet developed disease as the codon 129 PRNP genotype is MV, and all probable and definite vCJD cases to date have been MM at this loci. There have been four ‘possible’ cases of clinical vCJD, one of which was MV, but this was not biochemically confirmed and it was in a different birth cohort from the person from whom the tonsil in our study came 30. Also, the two IHC positives (out of three) from the previous study 26 for which a codon 129 genotype could be determined were PRNP codon 129VV 31 and no vCJD cases of this genotype have been reported.
The prevalence in the British population of underlying disease-related prion protein calculated from these findings is, if specimen 38 660 came from a vCJD-positive person, 109 per million for the 1961–1985 birth cohort, with a 95% confidence interval (CI) of 3–608 per million (Table 2), which is not different (exact p = 0.63) to the finding of three positives from 10 278 samples for the appendix survey 26. If tonsil 38 660 did not come from a vCJD-positive person, then the prevalence is 0 per million with an upper 95% CI of 403 for the 1961–1985 cohort and 0 per million for the 1961–1995 cohort with an upper 95% CI of 394 (Table 2), which is not different (exact p = 0.25) from the previous study.
It is possible that infection arising from exposure to BSE could cause more than one type of prion disease 32–34. Strains other than that resulting in vCJD, if they exist, may have markedly different pathogenesis, tissue distributions, and structural forms of PrPres. In addition, it is possible that genetic variability in the population may alter the pathogenesis of vCJD, in that the timing and rate of PrPres in appendix and tonsil tissues may differ between individuals. Indeed, genetic differences may even determine the extent of lymphoreticular pathogenesis 31.
Given that the collection of tonsils in our study has occurred later than the collection of appendix samples in the earlier appendix survey, it is conceivable that tonsils have been collected from infected individuals further into the incubation period than is the case for those individuals whose appendices were tested in the earlier survey 26. Moreover, should the incubation period for prion disease be considerably longer in people with different genotypes, uncertainty about the timing of the appearance of detectable PrPres in these will increase, with concomitant implications for the interpretation of results of PrPres prevalence surveys 6.
Animal experiments have shown that high infectivity, and even disease, can be present in the absence of detectable PrPres35. However, this observation cannot be generalized, as PrPres has always been detectable in the lymphoid tissues that have been tested from vCJD patients 6, 25, 28. Data from animal experiments also show ‘clearance’ of PrPres after inoculation 35, 36. Therefore, the PrPres found in the earlier survey of appendix tissue 26 may conceivably have been transient and eventually cleared without resulting in clinical disease, and therefore the result of the appendix survey result may not be replicable by the current tonsil survey 6.
Although, statistically, the vCJD prevalence estimates in this work do not differ significantly from those obtained by calculating from the previous Hilton study 26, qualitatively they suggest that prevalence estimates may be cautiously lowered. However, in an attempt to provide statistically significant evidence to demonstrate this, a large-scale IHC survey of recently collected appendix tissue specimens for the presence of PrPres is underway.
see full text ;
http://onlinelibrary.wiley.com/doi/10.1002/path.2767/full
>>> It is possible that infection arising from exposure to BSE could cause more than one type of prion disease 32–34. Strains other than that resulting in vCJD, if they exist, may have markedly different pathogenesis, tissue distributions, and structural forms of PrPres. In addition, it is possible that genetic variability in the population may alter the pathogenesis of vCJD, in that the timing and rate of PrPres in appendix and tonsil tissues may differ between individuals. Indeed, genetic differences may even determine the extent of lymphoreticular pathogenesis 31. <<<
2010 Tuesday, September 28, 2010
Variant CJD: where has it gone, or has it? Pract Neurol 2010; 10: 250-251
http://vcjdtransfusion.blogspot.com/2010/09/variant-cjd-where-has-it-gone-or-has-it.html
>>>CJD TEXAS 38 YEAR OLD FEMALE WORKED SLAUGHTERING CATTLE EXPOSED TO BRAIN AND SPINAL CORD MATTER >>>
Irma Linda Andablo CJD Victim, she died at 38 years old on February 6, 2010 in Mesquite Texas
Irma Linda Andablo CJD Victim, she died at 38 years old on February 6, 2010 in Mesquite Texas. She left 6 Kids and a Husband.The Purpose of this web is to give information in Spanish to the Hispanic community, and to all the community who want's information about this terrible disease.-
Physician Discharge Summary, Parkland Hospital, Dallas Texas
Admit Date: 12/29/2009 Discharge Date: 1/20/2010
Attending Provider: Greenberg, Benjamin Morris;
General Neurology Team:
General Neurology Team
Linda was a Hispanic female with no past medical history presents with 14 months of incresing/progressive altered mental status, generalized weakness, inability to walk, loss of appetite, inability to speak, tremor and bowel/blader incontinence. She was, in her usual state of health up until February, 2009, when her husbans notes that she began forgetting things like names and short term memories. He also noticed mild/vague personality changes such as increased aggression. In March, she was involved in a hit and run MVA,although she was not injured. The police tracked her down and ticketed her. At that time, her son deployed to Iraq with the Army and her husband assumed her mentation changes were due to stress over these two events. Also in March, she began to have weakness in her legs, making it difficult to walk. Over the next few months, her mentation and personality changes worsened, getting to a point where she could no longer recognized her children. She was eating less and less. She was losing more weight. In the last 2-3 months, she reached the point where she could not walk without an assist, then 1 month ago, she stopped talking, only making grunting/aggressive sounds when anyone came near her. She also became both bowel and bladder incontinent, having to wear diapers. Her '"tremor'" and body jerks worsened and her hands assumed a sort of permanent grip position, leading her family to put tennis balls in her hands to protect her fingers. The husband says that they have lived in Nebraska for the past 21 years. They had seen a doctor there during the summer time who prescribed her Seroquel and Lexapro, Thinking these were sx of a mood disorder. However, the medications did not help and she continued to deteriorate clinically.
Up until about 6 years ago, the pt worked at Tyson foods where she worked on the assembly line, slaughtering cattle and preparing them for packaging. She was exposed to brain and spinal cord matter when she would euthanize the cattle. The husband says that he does not know any fellow workers with a similar illness. He also says that she did not have any preceeding illness or travel.
http://www.recordandoalinda.com/index.php?option=com_content&view=article&id=19:cjd-english-info&catid=9:cjd-ingles&Itemid=8
Terry S. Singeltary Sr. has added the following comment: "According to the World Health Organisation, the future public health threat of vCJD in the UK and Europe and potentially the rest of the world is of concern and currently unquantifiable. However, the possibility of a significant and geographically diverse vCJD epidemic occurring over the next few decades cannot be dismissed
The key word here is diverse. What does diverse mean?
If USA scrapie transmitted to USA bovine does not produce pathology as the UK c-BSE, then why would CJD from there look like UK vCJD?"
SEE FULL TEXT ;
http://www.promedmail.org/pls/apex/f?p=2400:1001:568933508083034::NO::F2400_P1001_BACK_PAGE,F2400_P1001_PUB_MAIL_ID:1000,82101
.57 The experiment which might have determined whether BSE and scrapie were caused by the same agent (ie, the feeding of natural scrapie to cattle) was never undertaken in the UK. It was, however, performed in the USA in 1979, when it was shown that cattle inoculated with the scrapie agent endemic in the flock of Suffolk sheep at the United States Department of Agriculture in Mission, Texas, developed a TSE quite unlike BSE. 32 The findings of the initial transmission, though not of the clinical or neurohistological examination, were communicated in October 1988 to Dr Watson, Director of the CVL, following a visit by Dr Wrathall, one of the project leaders in the Pathology Department of the CVL, to the United States Department of Agriculture. 33 The results were not published at this point, since the attempted transmission to mice from the experimental cow brain had been inconclusive. The results of the clinical and histological differences between scrapie-affected sheep and cattle were published in 1995. Similar studies in which cattle were inoculated intracerebrally with scrapie inocula derived from a number of scrapie-affected sheep of different breeds and from different States, were carried out at the US National Animal Disease Centre. 34 The results, published in 1994, showed that this source of scrapie agent, though pathogenic for cattle, did not produce the same clinical signs of brain lesions characteristic of BSE.
32 Clark, W., Hourrigan, J. and Hadlow, W. (1995) Encephalopathy in Cattle Experimentally Infected with the Scrapie Agent, American Journal of Veterinary Research, 56, 606-12
33 YB88/10.00/1.1
http://web.archive.org/web/20040823105233/www.bseinquiry.gov.uk/files/yb/1988/10/00001001.pdf
SEE where sporadic cjd in the USA went from 59 cases in 1997, to 216 cases in 2009. a steady increase since 1997. ...TSS
Monday, August 9, 2010
National Prion Disease Pathology Surveillance Center Cases Examined (July 31, 2010)
Year Total Referrals2 Prion Disease Sporadic Familial Iatrogenic vCJD
1997 114 68 59 9 0 0
to
2009 425 259 216 43 0 0
http://www.cjdsurveillance.com/pdf/case-table.pdf
PLEASE SEE FULL TEXT HERE ;
Monday, August 9, 2010
National Prion Disease Pathology Surveillance Center Cases Examined (July 31, 2010)
(please watch and listen to the video and the scientist speaking about atypical BSE and sporadic CJD and listen to Professor Aguzzi)
http://prionunitusaupdate2008.blogspot.com/2010/08/national-prion-disease-pathology.html
Tuesday, August 03, 2010
Variably protease-sensitive prionopathy: A new sporadic disease of the prion protein
http://creutzfeldt-jakob-disease.blogspot.com/2010/08/variably-protease-sensitive-prionopathy.html
Monday, August 9, 2010
Variably protease-sensitive prionopathy: A new sporadic disease of the prion protein or just more PRIONBALONEY ?
http://prionunitusaupdate2008.blogspot.com/2010/08/variably-protease-sensitive-prionopathy.html
***+++***
Thursday, July 10, 2008
A Novel Human Disease with Abnormal Prion Protein Sensitive to Protease update July 10, 2008 Friday, June 20, 2008
http://cjdmadcowbaseoct2007.blogspot.com/2008/07/novel-human-disease-with-abnormal-prion.html
let's take a closer look at this new prionpathy or prionopathy, and then let's look at the g-h-BSEalabama mad cow.
This new prionopathy in humans? the genetic makeup is IDENTICAL to the g-h-BSEalabama mad cow, the only _documented_ mad cow in the world to date like this, ......wait, it get's better. this new prionpathy is killing young and old humans, with LONG DURATION from onset of symptoms to death, and the symptoms are very similar to nvCJD victims, OH, and the plaques are very similar in some cases too, bbbut, it's not related to the g-h-BSEalabama cow, WAIT NOW, it gets even better, the new human prionpathy that they claim is a genetic TSE, has no relation to any gene mutation in that family. daaa, ya think it could be related to that mad cow with the same genetic make-up ??? there were literally tons and tons of banned mad cow protein in Alabama in commerce, and none of it transmitted to cows, and the cows to humans there from ??? r i g h t $$$
ALABAMA MAD COW g-h-BSEalabama
In this study, we identified a novel mutation in the bovine prion protein gene (Prnp), called E211K, of a confirmed BSE positive cow from Alabama, United States of America. This mutation is identical to the E200K pathogenic mutation found in humans with a genetic form of CJD. This finding represents the first report of a confirmed case of BSE with a potential pathogenic mutation within the bovine Prnp gene. We hypothesize that the bovine Prnp E211K mutation most likely has caused BSE in "the approximately 10-year-old cow" carrying the E221K mutation.
http://www.plospathogens.org/article/info%3Adoi%2F10.1371%2Fjournal.ppat.1000156
http://www.plospathogens.org/article/fetchObjectAttachment.action?uri=info%3Adoi%2F10.1371%2Fjournal.ppat.1000156&representation=PDF
Saturday, August 14, 2010
BSE Case Associated with Prion Protein Gene Mutation (g-h-BSEalabama) and VPSPr PRIONPATHY
(see mad cow feed in COMMERCE IN ALABAMA...TSS)
http://prionpathy.blogspot.com/2010/08/bse-case-associated-with-prion-protein.html
2009 UPDATE ON ALABAMA AND TEXAS MAD COWS 2005 and 2006
http://bse-atypical.blogspot.com/2006/08/bse-atypical-texas-and-alabama-update.html
Monday, October 19, 2009
Atypical BSE, BSE, and other human and animal TSE in North America Update October 2009
http://bse-atypical.blogspot.com/2009/10/atypical-bse-bse-and-other-human-and.html
Tuesday, September 14, 2010
Feed Safety and BSE/Ruminant Feed Ban Support Project (U18)
http://madcowfeed.blogspot.com/2010/09/feed-safety-and-bseruminant-feed-ban.html
Tuesday, September 14, 2010
Transmissible Spongiform Encephalopathies Advisory Committee; Notice of Meeting October 28 and 29, 2010 (COMMENT SUBMISSION)
http://tseac.blogspot.com/2010/09/transmissible-spongiform_14.html
Friday, September 24, 2010
USA Blood products, collected from a donor who was at risk for vCJD, were distributed SEPTEMBER 2010
http://vcjdtransfusion.blogspot.com/2010/09/usa-blood-products-collected-from-donor.html
Wednesday, September 08, 2010
Emerging Infectious Diseases: CJD, BSE, SCRAPIE, CWD, PRION, TSE Evaluation to Implementation for Transfusion and Transplantation September 2010
http://vcjdtransfusion.blogspot.com/2010/09/emerging-infectious-diseases-cjd-bse.html
To date the OIE/WAHO assumes that the human and animal health standards set out in the BSE chapter for classical BSE (C-Type) applies to all forms of BSE which include the H-type and L-type atypical forms. This assumption is scientifically not completely justified and accumulating evidence suggests that this may in fact not be the case. Molecular characterization and the spatial distribution pattern of histopathologic lesions and immunohistochemistry (IHC) signals are used to identify and characterize atypical BSE. Both the L-type and H-type atypical cases display significant differences in the conformation and spatial accumulation of the disease associated prion protein (PrPSc) in brains of afflicted cattle. Transmission studies in bovine transgenic and wild type mouse models support that the atypical BSE types might be unique strains because they have different incubation times and lesion profiles when compared to C-type BSE. When L-type BSE was inoculated into ovine transgenic mice and Syrian hamster the resulting molecular fingerprint had changed, either in the first or a subsequent passage, from L-type into C-type BSE. In addition, non-human primates are specifically susceptible for atypical BSE as demonstrated by an approximately 50% shortened incubation time for L-type BSE as compared to C-type. Considering the current scientific information available, it cannot be assumed that these different BSE types pose the same human health risks as C-type BSE or that these risks are mitigated by the same protective measures.
http://www.prionetcanada.ca/detail.aspx?menu=5&dt=293380&app=93&cat1=387&tp=20&lk=no&cat2
Saturday, October 2, 2010
BSE surveillance front and centre: CFIA and USA
http://madcowtesting.blogspot.com/2010/10/bse-surveillance-front-and-centre-cfia.html
SOME HISTORY ON TONSIL SPECIMENS
Friday, December 12, 2008
Creutzfeldt-Jakob disease (CJD) update report Emerging Infections/CJD Published on: 12 December 2008
http://creutzfeldt-jakob-disease.blogspot.com/2008/12/creutzfeldt-jakob-disease-cjd-update.html
In this update:
Archive Number 20100107.0076 Published Date 07-JAN-2010 Subject PRO/AH/EDR> Prion disease update 2010
PRION DISEASE UPDATE 2010
**************************
A ProMED-mail post
ProMED-mail is a program of the International Society for Infectious Diseases
[With the continuing decline in the number of cases in the human population of variant Creutzfeldt-Jakob disease -- abbreviated previously as vCJD or CJD (new var.) in ProMED-mail -- it has been decided to broaden the scope of the occasional ProMED-mail updates to include some other prion-related diseases. In addition to vCJD, data on other forms of CJD: sporadic, iatrogenic, familial, and GSS (Gerstmann-Straussler-Scheinker disease), are included also since they may have some relevance to the incidence and etiology of vCJD. - Mod.CP]
In this update: [1] UK: National CJD Surveillance Unit - monthly statistics as of 5 Jan 2010 [2] France: Institut de Veille Sanitaire - monthly statistics as of 4 Jan 2010 [3] US National Prion Disease Center - not updated since 7 Nov 2009 [4] Portuguese vCJD case - pathology [5] vCJD codon 129 heterozygote [6] vCJD codon 129 heterozygote - Lancet paper [7] Prion evolution & a new reagent
****** [1] UK: National CJD Surveillance Unit - monthly statistics as of 5 Jan 2010 Date: Tue 5 Jan 2010 Source: UK National CJD Surveillance Unit, monthly statistics [edited]
The number of deaths due to definite or probable vCJD cases remains 166. A total of 4 definite/probable patients are still alive, so that the total number of definite or probable vCJD cases remains 170 for the year 2009.
Although 2 new cases vCJE were recorded in 2009, the overall picture is still consistent with the view that the vCJD outbreak in the UK is in decline, albeit now with a pronounced tail. The 1st cases were observed in 1995, and the peak number of deaths was 28 in the year 2000, followed by 20 in 2001, 17 in 2002, 18 in 2003, 9 in 2004, 5 in 2005, 5 in 2006, 5 in 2007, one in 2008, and 2 in 2009.
Totals for all types of CJD cases in the UK in the year 2009
--------------------------------------------
During the 12 months of 2009, there have been 143 referrals, 59 cases of sporadic CJD, one case of familial CJD, one case of iatrogenic CJD, 3 cases of GSS, and 2 cases of vCJD.
-- Communicated by: ProMED-mail
****** [2] France: Institut de Veille Sanitaire - monthly statistics as of 4 Jan 2010 Date: Mon 4 Jan 2010 Source: IVS - Maladie de Creutzfeldt-Jakob et maladies apparentees [in French, trans. & summ. Mod.CP]
During the 12 months of 2009, there were 1486 referrals, 85 cases of sporadic CJD, 10 cases of familial CJD, 3 cases of iatrogenic CJD, and 2 confirmed cases of vCJD.
A total of 25 cases of confirmed or probable vCJD has now been recorded in France since 1997. The 25 confirmed cases comprise 13 females and 12 males. All 25 are now deceased. Their median age is 37 (between 19 and 58). Seven were resident in the Ile-de-France and 18 in the provinces. All the identified cases have been Met-Met homozygotes. No risk factor has been identified. One of the 25 had made frequent visits to the United Kingdom.
-- Communicated by: ProMED-mail
****** [3] US National Prion Disease Center - not updated since 7 Nov 2009 Date: Sat 7 Nov 2009
Source: US National Prion Disease Pathology Surveillance Center [edited]
(Report not updated since 7 Dec 2009): During the period 1 Jan 2009 to 7 Nov 2009, there were 341 referrals, of which 198 were classified as Prion disease, comprising 133 cases of sporadic CJD, 33 of familial CJD, and no cases of iatrogenic CJD or vCJD.
-- Communicated by: ProMED-mail
****** [4] Portuguese vCJD case - pathology Date: Fri 1 Jan 2010 Source: J Neurol Neurosurg Psychiatry 2010 Jan;81(1):112-4. [edited]
Title: Variant Creutzfeldt-Jakob disease: the first confirmed case from Portugal shows early onset, long duration and unusual pathology.
Authors: Barbot C, Castro L, Oliveira C, Carpenter S. At: Department of Neuropaediatrics, Hospital Maria Pia, Porto, Portugal.
Summary: We present clinical and autopsy findings in the 1st case of variant Creutzfeldt-Jakob disease diagnosed and confirmed in Portugal. Onset was at 11 years, the earliest onset reported, and the course (32 months) relatively long. Western blot showed protease resistant prion protein, mainly of type 4 (2B) isoform. The cerebral cortex revealed severe spongiform change with numerous amyloid plaques, which did not fit the definition of florid plaques. In the striatum, spongiform change was limited, but the extracellular space was dilated. Other reports have found marked spongiform change in the striatum and little in the cortex. Massive neuronal loss, in excess of what has been described, was found in the thalamus and pontine grey. The cerebellum showed, as expected, severe loss of granule cells, moderate loss of Purkinje cells and marked immunopositivity for the prion protein. Differences between our findings and previous ones probably result from the patient's long survival.
-- Communicated by: Terry S. Singeltary Sr.
****** [5] vCJD codon 129 heterozygote Date: Fri 19 Dec 2009 Source: BBC News, Health [edited]
A 30-year-old man thought to have died in January [2009] from vCJD belonged to a genetic group that had not shown any signs of the disease, scientists say. In the UK, 166 people have died of vCJD, linked to eating BSE [bovine spongiform encephalopathy] infected beef, and all were thought to have shared a certain gene.
Writing in the Lancet, scientists say that the victim, a resident of, Lanarkshire [Scotland], had a different version of the gene. They estimate that up to 350 people in this group could get vCJD. Scientists have always thought that a 2nd wave of vCJD cases would emerge some time after the 1st. This is the 1st indication that this theory is being born out, with the identification of the 1st probable vCJD patient outside of the initial genetic group, BBC science correspondent Pallab Ghosh reports.
The father believes his son was incubating the disease for much of his life. It is probable because the diagnosis is based on observations of the progression of the disease rather than post-mortem tests which would have provided absolute confirmation of the disease, he adds.
The case report written by Professor John Collinge of the National Prion Clinic and colleagues is a reminder that the disease has not gone away. Many thousands of people may be carrying the infection, and although they will never show any symptoms, they have the potential to infect others.
vCJD is caused by infectious agents called prions. Prion diseases affect the structure of the brain or other neural tissue and are currently untreatable. Disease-causing prions are thought to consist of abnormally folded proteins, which spread by encouraging the normal healthy prion protein found on the surface of most cells in the body to change shape. Tests showed that the patient had a heterozygous version of the gene which codes for the human prion amino acids valine (V) or methionine (M). People can be V V (homozygous), M M (homozygous) or M V (heterozygous). Since 1994, around 200 cases of vCJD have been identified worldwide, and all those tested have been M M homozygous. [However, genetic analysis of 2 out of 3 prion-positive appendix samples in the tissue-based prevalence study in 2001-2004 showed that both were valine homozygous (VV) at codon 129 in the prion protein gene (Ironside et al, Brit Med J 2006). - Mod.CP]. However, this most recent victim was M/V heterozygous. It is thought that 47 percent of the population have this version of the gene. Professor Collinge said: "The majority of the UK population have potentially been exposed to BSE prions, but the extent of clinically silent infection remains unclear. About 1/3rd of the UK population are M/M homozygous. If individuals with other genotypes [M/V and V/V] are similarly susceptible to developing prion disease after BSE prion exposure, but with longer incubation periods, further cases would be expected."
The scientists have previously looked at another prion disease in New Guinea called "kuru" [which was induced by eating infected human brain tissue. - Mod.CP]. The original cases were all M/M, but more recently, M/V cases have appeared. They say this indicates that M/V people can get prion diseases like kuru but have a much longer incubation period.
-- Communicated by: ProMED-mail
[The abstract of the Lancet paper upon which the above report is based is reproduced below. - Mod.CP]
****** [6] vCJD codon 129 heterozygote - Lancet paper Date: Thu 18 Dec 2009 Source: Lancet 2009; 374: 2128 [edited]
[A Case Report published in the 18 Dec 2009 issue of the Lancet by Professor John Collinge, MRC Prion Unit and National Prion Clinic, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London]
A 30-year-old man was admitted to hospital in June 2008 with a 13-month history of personality change, progressive unsteadiness, and intellectual decline. He complained of severe leg pain and poor memory. Two months later, he developed visual hallucinations and falsely believed he had an abdominal tumour. Symptoms worsened over the next 3 months. In October 2008, his score on the mini mental state examination was 26/30. Pursuit eye movements were saccadic [a rapid movement of the eye between fixation points]. He had a pout reflex. There was mild ataxia in the arms. His legs were severely ataxic with brisk tendon reflexes and a left extensor plantar response. He needed 2 crutches to walk. Medical history included tonsillectomy and removal of a cervical lymph node 15 years previously, but he had never had a blood transfusion or received implantation of other human tissues.
EEG showed slow wave activity. CSF protein, glucose, and cell count were normal, but the 14-3-3 protein was positive. MRI [magnetic resonance imaging] of the brain was consistent with the pulvinar sign (illustrated in the original text). Although not all neuroradiologists consulted considered the pulvinar sign positive, quantitative assessment showed symmetrical higher signal in the pulvinar nuclei than the caudate nuclei (illustrated in the original text). Extensive screens for genetic, metabolic, and autoimmune diseases, including those induced by neoplasia, were negative. PRNP analysis did not show any known disease-associated mutations; codon 129 was heterozygous. A clinical diagnosis of variant Creutzfeldt-Jakob disease (vCJD) was made on the basis of a characteristic clinical onset and progression, exclusion of other diagnoses, and MRI findings. Sporadic CJD was judged unlikely given the combination of young age, clinical features, MRI findings, and absence of pseudoperiodic complexes on EEG. His care givers did not want further investigation. His condition deteriorated, and he died in January 2009. Autopsy was not done.
Human prion diseases have acquired, sporadic, and inherited aetiologies, show wide phenotypic heterogeneity, and are associated with propagation of infectious prions of many distinct strain types (1). Since 1994, about 200 cases of vCJD, causally related to exposure to bovine spongiform encephalopathy (BSE) prions, have been identified world-wide. vCJD is generally seen in young adults, has characteristic neuropathological features and tissue distribution of infectivity, and a distinctive type 4 (London classification) molecular strain type (1). A polymorphism at codon 129 (encoding methionine or valine) of the human prion protein gene (PRNP) constitutes a powerful susceptibility factor in all types of prion disease. In vCJD, every case genotyped to date has been methionine homozygous. In the other acquired prion diseases, cases have occurred in all genotypes but with different mean incubation periods (1), which can span decades (2); PRNP codon 129 heterozygotes generally have! the longest incubation periods. There is a report of a recipient of a blood transfusion from a donor incubating vCJD who died of unrelated causes but showed signs of prion infection at autopsy and was PRNP codon 129 heterozygous (3). Animal studies have suggested that different clinicopathological phenotypes could occur in people with various PRNP codon 129 genotypes (4,5). The majority of the UK population have potentially been exposed to BSE prions but the extent of clinically silent infection remains unclear. About 1/3rd of the UK population are PRNP codon 129 methionine homozygous. If individuals with other genotypes [V/V or V/M] are similarly susceptible to developing prion disease after BSE prion exposure, but with longer incubation periods, further cases, which may or may not meet diagnostic criteria for vCJD, would be expected in these PRNP codon 129 genotypes. However, prion disease susceptibility and incubation periods are also affected by other genetic loci, and the possibility remains that cases of vCJD to date may have unusual combinations of genotypes at these loci, yet to be fully characterised.
References:
(1) Collinge J. Prion diseases of humans and animals: their causes and molecular basis. Annu Rev Neurosci 2001; 24: 519-50.
(2) Collinge J, Whitfield J, McKintosh E, et al. Kuru in the 21st century - an acquired human prion disease with very long incubation periods. Lancet 2006; 367: 2068-74.
(3) Peden AH, Head MW, Ritchie DL, Bell JE, Ironside JW. Preclinical vCJD after blood transfusion in a PRNP codon 129 heterozygous patient. Lancet 2004; 364: 527-29.
(4) Asante E, Linehan J, Gowland I, et al. Dissociation of pathological and molecular phenotype of variant Creutzfeldt-Jakob disease in transgenic human prion protein 129 heterozygous mice. Proc Natl Acad Sci USA 2006; 103: 10759-64.
(5) Wadsworth JD, Asante E, Desbruslais M, et al. Human prion protein with valine 129 prevents expression of variant CJD phenotype. Science 2004; 306: 1793-96.
[Acknowledgment: MRC Prion Unit and National Prion Clinic, UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery, London, UK (D Kaski MRCP, S Mead PhD, H Hyare FRCR, Prof J Collinge FRS, P Rudge FRCP); Institute of Neurological Sciences, Glasgow University, Glasgow, UK (S Cooper MRCP, R Jampana FRCR, J Overell FRCP); and National CJD Surveillance Unit, Western General Hospital, Edinburgh, UK (Prof R Knight FRCP)]
-- Communicated by: ProMED-mail
[To put this work in perspective, parts of a British Medical Journal editorial by Maurizio Pocchiari are reproduced below. - Mod.CP.
Date: 21 May 2009 Source: BMJ 2009;338:b435 [edited]
"Prevalence of variant CJD in the UK
----------------------------
The number of cases of variant Creutzfeldt-Jakob disease (vCJD) in the United Kingdom has decreased since 2000, but controversy remains about how many people carry the infectious agent and will eventually develop disease. Clewley and colleagues in a limited study add to the debate by assessing 63 007 pairs of tonsils for the only available marker of prion disease, the pathological, partially protease resistant, prion protein. Although more than half of the samples came from people born between 1961 and 1995, when the risk of exposure to bovine spongiform encephalopathy (BSE) infection was high, no convincingly positive tonsil specimens were detected. This study estimated that the prevalence of vCJD in the British population is zero, but with a large confidence interval of 0 to 113 per million.
This result agrees with one UK survey of 2000 tonsil specimens, but it differs from another survey of 1427 tonsils and 11 247 appendices, which found that more than 10 000 people might be incubating the disease. However, despite the discrepancy, the 95 percent confidence intervals of the 2 studies overlap, indicating that the results do not differ significantly and that many people in the UK may be carriers.
The chance that no one in the UK is incubating the disease, as suggested by the lower confidence limit of Clewley and colleagues' study, is unlikely because backup calculations predict up to 100 new cases of vCJD in the next 50 years. This prediction seems reasonable unless most cases of vCJD were missed by surveillance in the past years.
Until December 2008, all 210 people reported to have vCJD (164 in the UK, 46 in other countries) were homozygous for methionine at the polymorphic codon 129 of the prion protein gene (PRNP), suggesting that genetic factors strongly influence the development of disease. Whether people who are heterozygous for methionine and valine or homozygous for valine at this codon (about 60 percent of the population) will develop vCJD in the future is still unknown. However, data from gene targeted transgenic mice indicate that these people are also susceptible to BSE and vCJD, although incubation periods are longer than in those who are homozygous for methionine."
Interested readers should consult the original article for further information and references. - Mod.CP]
****** [7] Prion evolution & a new reagent Date: 1 Jan 2010 Source: BBC Health News [edited]
Abnormal prion proteins cause at least 20 fatal diseases. Scientists have shown for the 1st time that "lifeless" prion proteins, devoid of all genetic material, can evolve just like higher forms of life. The Scripps Research Institute in the US says the prions can change to suit their environment and go on to develop drug resistance.
Prions are associated with 20 different brain diseases in humans and animals. The scientists say their work suggests new approaches might be necessary to develop therapies for these diseases. In the study, published in the journal Science [see below], the scientists transferred prion populations from brain cells to other cells in culture and observed the prions that adapted to the new cellular environment out-competed their brain-adapted counterparts. When returned to the brain cells, the brain-adapted prions again took over the population.
Charles Weissmann, head of Scripps Florida's department of infectology who led the study, said: "On the face of it, you have exactly the same process of mutation and adaptive change in prions as you see in viruses. This is a timely reminder that prion concerns are not going away and that controls to stop abnormal prions being transmitted to humans through the food system or through blood transfusions must be vigorously maintained."
Professor John Collinge, Medical Research Council Prion Unit stated that: "This means that this pattern of Darwinian evolution appears to be universally active. In viruses, mutation is linked to changes in nucleic acid sequence that leads to resistance. Now, this adaptability has moved one level down -- to prions and protein folding -- and it's clear that you do not need nucleic acid (DNA or RNA) for the process of evolution."
Mammalian cells normally produce cellular prion protein or PrPC. During infections, such as the human form of mad cow disease, known as vCJD, abnormal or mis-folded proteins convert the normal host prion protein into its toxic form by changing its conformation or shape. "It was generally thought that once cellular prion protein was converted into the abnormal form, there was no further change," Prof. Weissmann said. "But there have been hints that something was happening. When you transmit prions from sheep to mice, they become more virulent over time. Now we know that the abnormal prions replicate and create variants, perhaps at a low level initially. But once they are transferred to a new host, natural selection will eventually choose the more virulent and aggressive variants."
Professor John Collinge, of the Medical Research Council's (MRC) Prion Unit, described the research as exciting confirmation of a hypothesis that he had proposed 2 years ago, that there could be a "cloud" or whole array of prion proteins in the body. He called it the cloud hypothesis: "The prion protein is not a clone, it is a quasi-species that can create different protein strains even in the same animal. The abnormal prion proteins multiply by converting normal prion proteins. The implication of Charles Weissmann's work is that it would be better to cut off that supply of normal prion proteins rather than risk the abnormal prion adapting to a drug and evolving into a new more virulent form. You would do this by trying to block the sites on the normal prion protein that the abnormal form locks on to to do its conversion. We know there is an antibody that can do this in mice, and the Medical Research Council's Prion Unit have managed to engineer a human antibody to do this. It is currently undergoing safety tests, and we hope to move to clinical trials by the end of 2011."
Professor Collinge said the MRC was also trying to find more conventional chemical compounds to do this and has been collaborating with the chemical company GlaxoSmithKline (GSK). He said: "They have given us access to their chemical libraries, which contain millions of compounds, and we have already identified some that may work well. This is a timely reminder that prion concerns are not going away and that controls to stop abnormal prions being transmitted to humans through the food system or through blood transfusions must be vigorously maintained."
-- Communicated by: ProMED-mail
[The abstract and the reference for the Science paper descried above are the following: Science DOI: 10.1126/science.1183218, Published Online 31 Dec 2009.
Abstract: "Prions are infectious proteins consisting mainly of PrPSc, a sheet-rich conformer of the normal host protein PrPC, and occur in different strains. Strain identity is thought to be encoded by PrPSc conformation. We found that biologically cloned prion populations gradually became heterogeneous by accumulating "mutants," and selective pressures resulted in the emergence of different mutants as major constituents of the evolving population. Thus, when transferred from brain to cultured cells, "cell-adapted" prions out competed their "brain-adapted" counterparts, and the opposite occurred when prions were returned from cells to brain. Similarly, the inhibitor swainsonine selected for a resistant substrain, whereas in its absence, the susceptible substrain outgrew its resistant counterpart. Prions, albeit devoid of a nucleic acid genome, are thus subject to mutation and selective amplification."
From a theoretical standpoint, this work has great significance. Nonetheless, the immediate interest of the BBC News report is the information that Professor John Collinge's MRC group has succeeded in engineering a humanised monoclonal antibody that interacts with the sites on the normal prion protein that the abnormal form locks onto to achieve its conversion and that it is hoped eventually to move to clinical trials of this reagent. - Mod.CP]
[see also: 2009 ----
http://www.promedmail.org/pls/apex/f?p=2400:1001:96390448179630::::F2400_P1001_BACK_PAGE,F2400_P1001_ARCHIVE_NUMBER,F2400_P1001_USE_ARCHIVE:1202,20100107.0076,Y
===================================
[1] UK DOH vCJD monthly statistics - as of 7 Feb 2005; one more case
[2] UK - estimate of future cases reduced to 70
[3] [4] & [5] Inflammation and prion movement
[6] SEAC position paper - maternal transmission
[7] Blood supply - new technology for removal of prions
****** [1] Date: Fri 11 Feb 2005
From: ProMED-mail
Source: UK Department of Health, Monthly Creutzfeldt-Jakob Disease Statistics, Press release, Mon 7 Feb 2005 [edited]
[The UK Department of Health web-site has been revised, and the monthly new variant Creutzfeldt-Jakob disease statistics are now appended to the table "Creutzfeldt-Jakob disease in the UK by Calendar Year (since 1990)" which can be accessed at
http://www.dh.gov.uk/assetRoot/04/10/27/72/04102772.pdf
The definition of the designations deaths, definite cases, probable vCJD cases, and, the case definitions can be found by accessing the Department of Health web-site or by reference to a previous ProMED-mail post (for example, CJD (new var.) - UK: update Mar 2002 20020305.3693)
The incidence of variant Creutzfeldt-Jakob disease, abbreviated CJD (new var.) or vCJD in ProMED-mail, in the UK appears to have plateaued, or perhaps to be in decline. Therefore, since many of the reports appearing in the update are only peripherally related to the situation in the UK, the opportunity is being taken to drop the designation UK from the title of this thread. - Mod.CP]
Monthly Variant Creutzfeldt-Jakob Disease Statistics as of Mon 10 Jan 2005
---------------------------------------------------
The UK Department of Health is today [Mon 7 Feb 2005] issuing the latest information about the numbers of known cases of Creutzfeldt-Jakob disease. This includes cases of variant Creutzfeldt-Jakob disease (vCJD), the form of the disease thought to be linked to BSE. The position is as follows:
Definite and probable CJD cases in the UK:
Summary of vCJD cases - Deaths
------------------------------
Deaths from definite vCJD (confirmed): 106 Deaths from probable vCJD (without neuropathological confirmation): 41 Deaths from probable vCJD (neuropathological confirmation pending): 1 Total number of deaths from definite or probable vCJD (as above): 148
Summary of vCJD cases - Alive
-----------------------------
Number of probable vCJD cases still alive: 6
Total ------ Number of definite or probable vCJD (dead and alive): 154
(The next update will be published on Mon 7 Mar 2005)
[Since the previous monthly statistics were released on Mon 11 Jan 2004, the number of deaths from definite vCJD is unchanged at 106, and the total number of deaths from definite or probable vCJD is unchanged and remains 148. The number of probable vCJD cases still alive has increased from 5 to 6. Therefore the overall total number of definite or probable vCJD cases has increased by one since 11 Jan 2004 to 154.
As of 4 Feb 2005, so far this year in the UK there have been 8 referrals of suspected CJD; and there have been 4 deaths from sporadic CJD, one from GSS, and none from Familial, iatrogenic or variant CJD. - Mod.CP]
****** [2] Date: Wed 12 Jan 2005 From: ProMED-mail
"vCJD Timebomb" Fears Discounted
High numbers of future deaths in the UK from the human form [variant Creutzfeldt-Jakob disease of mad cow disease (bovine spongiform encephalopathy)] are unlikely, researchers have said. The Imperial College team [now] calculate there will be around 70 future deaths. They say the worst-case scenario could see another 600 deaths, but that this is unlikely. The research, which appears in the Journal of the Royal Society, said thousands of people could carry vCJD, but show no symptoms.
The higher forecast is based on the possibility that people from different genetic subgroups could be affected by vCJD. So far, people of only one genetic subgroup, which accounts for 40 percent of the population, have been affected. There have been 148 deaths from new-variant Creutzfeldt-Jakob disease (vCJD) since the condition was first seen in 1995. Research pointed to eating meat contaminated with bovine spongiform encephalopathy (BSE) as the cause. Over the last decade, scientists have been working to evaluate what the full extent of the vCJD epidemic will be. Deaths have been declining from their peak of 28 in 2000 to 9 in 2004.
But researchers who tested 12 674 appendix and tonsil samples found that 3 showed signs of apparent vCJD, indicating around 3800 people could ultimately be affected. However, only one of the 3 positive samples actually matched those taken from people who had been diagnosed with the clinical disease. Interpretation of the other 2 samples was less certain because they did not look [precisely] as scientists expected. The Imperial College team suggest this could mean that some people could be infected with vCJD, but not develop symptoms. If this was the case, looking at the population who would have eaten infected meat, computer programmes were used to estimate there could be a total of around 70 deaths from vCJD.
In addition, the Imperial team considered research into the genetics of those who could be affected. Until 2004, all of those affected had been from one genetic subgroup. But it was then revealed that someone with a different genetic make-up had probably become infected with vCJD after a blood transfusion. The researchers say that in this worst-case scenario -- if people of other genotypes are equally as susceptible as those in the original subgroup, but have a longer incubation period for vCJD -- there could be a total of around 600 deaths from vCJD.
Dr Azra Ghani, from Imperial College, said: "Since 2000 there has been a decline in the number of clinical cases reported. One reason for the discrepancy between the high estimated number of positive tests and low number of actual recorded clinical cases could be that infected individuals do not go on to develop clinical disease in their lifetime." However, the researchers say they have been unable to calculate how many vCJD cases could result in the future from blood transfusions from people who do not know they are carriers of the disease.
Dr Ghani said: "Although our results indicate there is little chance of large numbers of vCJD infections from primary transmission, we have not taken into account the possibility of additional cases infected by blood transfusion. This could result in more clinical cases emerging at a later date."
The CJD Surveillance Unit said predicting the extent of vCJD was very difficult, but said the more research was carried out, the more accurate predictions could be.
http://news.bbc.co.uk/2/hi/health/4162749.stm
-- ProMED-mail promed@promedmail.org
****** [3] Date: Thu 20 Jan 2005 From: Terry S. Singeltary Sr.
Chronic Lymphocytic Inflammation Specifies the Organ Tropism of Prions
-----------------------
[The following is the summary of a paper by Mathias Heikenwalder and 8 others, published in Science online, 10.1126/science.1106460, Thu 20 Jan 2005
http://www.sciencemag.org/cgi/content/abstract/1106460v1
This paper describes work that illustrates that chronic inflammatory conditions may affect and expand the natural and iatrogenic transmission of prions - Mod.CP]
Prions typically accumulate in nervous and lymphoid tissues. Because proinflammatory cytokines and immune cells are required for lymphoid prion replication, we tested whether inflammatory conditions affect prion pathogenesis. We administered prions to mice with 5 inflammatory diseases of kidney, pancreas or liver. In all cases, chronic lymphocytic inflammation enabled prion accumulation in otherwise prion-free organs. Inflammatory foci consistently correlated with lymphotoxin upregulation and ectopic induction of PrPC-expressing FDC-M1+ cells, whereas inflamed organs of mice lacking lymphotoxin-alpha or its receptor accumulate neither PrPSc nor infectivity upon prion inoculation. By expanding the tissue distribution of prions, chronic inflammatory conditions may act as modifiers of natural and iatrogenic prion transmission.
****** [4] Date: Thu 20 Jan 2005 From: Terry S. Singeltary Sr.
Study Finds Illness May Promote Spread Of Mad Cow Prion
(Reuters) -- The agent that transmits mad cow disease and related diseases may spread further in the body of an animal suffering from certain illnesses, scientists said on Thu 20 Jan 2005. Their finding raises the question of whether measures aimed at curbing the spread of mad cow disease, or bovine spongiform encephalopathy (BSE), are adequate, the researchers said.
Tests on mice showed that prions, the protein-like fragments that transmit BSE and related diseases [e.g. variant Creutzfeldt-Jakob disease in humans], can show up in organs they are not supposed to if the mouse has an inflammatory condition. Scientists have believed that BSE-causing prions are limited to the brain, spleen, spinal cord and lymph tissue, although some tests have suggested blood and muscle tissue may also harbor the prions. The latest study, published in the journal Science, suggests prions may also sometimes be found in the kidney, pancreas and liver. "We administered prions to mice with 5 inflammatory diseases of kidney, pancreas or liver," wrote the researchers, led by top prion expert Dr. Adriano Aguzzi of the University Hospital of Zurich in Switzerland.
Aguzzi and colleagues in Britain and the United States inoculated specially bred mice with prions and checked to see if the prions spread in their bodies when the mice had an inflammatory condition. This is because other studies had suggested that prions might be attracted to immune system inflammatory cells. "In all cases, chronic lymphocytic inflammation enabled prion accumulation in otherwise prion-free organs," the researchers wrote.
BSE peaked in British cattle herds in the mid-1990s, and a few cases have been reported in other countries. Canada reported its 3rd case this month. People who eat BSE-infected beef products can develop a related human brain disease called variant Creutzfeldt-Jakob disease or vCJD. There is no treatment or cure. [As of 4 Feb 2005, so far in the UK for the year 2005 there have 8 referrals of suspected CJD; and there have been 8 deaths from sporadic CJC, one from GSS and none from familial, iatrogenic or variant CJD. - Mod.CP]. It has killed 148 Britons, and 5 [now 6] Britons are alive with the disease, according to the British Department of Health's monthly report on the disease. The World Health Organization says it has reports of 6 cases in France, one in Ireland, one in Italy, one in Canada and one in the United States [and one in Japan: see; ProMED-mail post "CJD (new var.) - Japan: death 20050204.0381" - Mod.CP]
Experts believed BSE first appeared when cattle were fed improperly rendered remains of sheep infected with scrapie, a related disease. In 1997, the United States and Canada imposed animal feed bans, and have mandated the removal of materials believed to carry infectious prions. These include the skull, brain, nerves attached to the brain, eyes, tonsils, spinal cord and attached nerves, plus a portion of the small intestine. The study suggests that even symptom-free animals may also have prions in their liver, kidney, and pancreas.
http://www.reuters.com/newsArticle.jhtml?type=healthNews&storyID=7385700 -- Terry S. Singeltary Sr. flounder@wt.net
****** [5] Date: Fri 21 Jan 2005 From: ProMED-mail
Study Finds Broader Reach For Mad Cow Proteins
By Sandra Blakeslee NY Times
Mad cow disease has long been thought to occur in just the brains and nervous systems of infected animals. But scientists are reporting today that the proteins thought to cause the disease can travel to other organs as well. The research is based on experiments with mice, but if it is borne out in other species, it may suggest that no part of an infected animal is safe to eat. The disease leads to a fatal brain disease in humans [variant Creutzfeldt-Jakob disease].
In the mouse experiments, reported in the journal Science [see [3] above], researchers in Switzerland found that prions, proteins that are the infectious agent in mad cow disease, follow immune cells, called lymphocytes, in the body. When mice were given chronic infectious diseases of the liver, kidney and pancreas and then inoculated with prions, the prions made their way to the infected organs. Dr. Adriano Aguzzi, a neuropathologist at the University Hospital in Zurich, who led the experiments, said this meant that cows and sheep infected with prions could harbor the disease in any inflamed organ.
But Dr. David R. Smith, a veterinarian at the University of Nebraska, said the research did not raise alarms about American beef. For one thing, he said, livestock with obvious signs of systemic infection, like a fever, are not allowed into the food supply. And most American cattle are slaughtered while they are young and at reduced risk of infection.
Many countries, including the United States, require the removal of skulls, brains, eyes, spinal cords and other nervous tissues from slaughtered animals because prions are known to accumulate in those tissues. Even in countries with mad cow disease, mainly in Europe, meat is considered safe if those tissues are removed, Dr. Aguzzi said. But the disease could spread more readily if infections are not obvious or if inspections are sloppily done, he said.
http://www.nytimes.com/2005/01/21/national/21disease.html?oref=login
-- ProMED-mail promed@promedmail.org
****** [6] Date: Fri 4 Feb 2005 From: Terry S. Singeltary Sr.
http://www.seac.gov.uk/statements/cjdtransmissionfinal.pdf
Position Statement: Maternal Transmission of variant Creutzfeldt-Jakob disease
Issue:
1. The Chief Medical Officer for England asked SEAC to consider current evidence and comment on the potential transmission of variant Creutzfeldt-Jakob disease (vCJD) from mother to child via human breast milk. In utero transmission was also considered. The committee also commented on the scientific basis of a risk reduction measure for possible transmission of vCJD via banked breast milk.
Background:
2. No diagnostic test is currently available for the detection of abnormal PrP in milk. Research is under way to develop tests to screen for the possible presence of abnormal prion protein (PrP) in milk samples from cattle experimentally infected with BSE [A joint FSA/SEAC milk working group is monitoring and providing advice on this research carried out at the Veterinary Laboratories Agency.] These modified tests may also be applicable to human milk. However, it is not yet clear when/if a reliable test will be available.
3. A small number of breast milk banks in the UK supply highly vulnerable premature babies for whom no milk may be available from the mother. A model developed by the Department of Health to assess the effect of pooling breast milk from multiple donors on the possible risks of transmission of vCJD via breast milk banks was considered.
4. There is some, albeit limited, published epidemiological and experimental research on maternal transmission of prion diseases. There are also unpublished surveillance data of children born to vCJD cases from the National CJD Surveillance Unit and UK surveillance of neurological illness in children which might inform on potential risks of maternal transmission.
Breast milk banks:
5. There is no evidence that vCJD infectivity has ever been transmitted through breast milk. However, a theoretical risk exists. Modelling studies clearly show that the practice of pooling breast milk increases the number of donors to which a recipient is exposed and thereby increases the potential risk of an infant receiving milk contaminated with vCJD infectivity. The theoretical risk of infection can be minimised by not pooling the milk, by the use of individual hand operated breast milk pumps for single donors, and by the use of single-use sterilised bottles for collection. In addition, available evidence suggests that infection/inflammation of the breast results in increased lymphocytes in milk and therefore increased risk of infectivity. This risk would be minimised if milk from donors showing signs of infection were not used.
6. The committee suggested that, if practicable, milk could be stored for an appropriate period of time to allow the health status of donors to be monitored, before it is released. However, information was not available to the committee on whether long-term storage of human milk is detrimental to its nutritional quality. Maternal transmission
7. There is evidence from animal studies for low-level maternal transmission of prions in cattle and sheep. This transmission may occur in utero, via milk and/or perinatally. However, the possibility that this putative maternal transmission might have been due to another mode of transmission, for example through a contaminated environment or feed, cannot be ruled out.
8. In contrast, in humans there is no evidence for maternal transmission in cases of familial prion disease, other than the transfer of a mutant form of the PrP gene, and there is no evidence of maternal transmission of Kuru [a chronic, progressive, uniformly fatal nervous system disorder caused by prions, associated with cannibalism among the Fore tribe and neighboring peoples in New Guinea. - CopyEd.PG]. However, compared with other human prion diseases vCJD may pose a greater risk because of the greater involvement of the lymphoreticular system in vCJD pathogenesis. Although, breast tissue (and placenta) from a single vCJD case tested negative for PrPvCJD, transfer of infectivity to breast milk may depend on the physiological status of the mammary gland. Similar tests or infectivity bioassays have not been conducted on breast tissue from lactating patients with vCJD.
9. A published study suggesting transmission of sCJD in colostrum (ref. 1) was considered unreliable because tissues not normally associated with high levels of infectivity (blood and placenta) showed equivalent infectivity to that of the brain in this study.
10. Analysis of prospective surveillance data of UK children born to mothers with, or that had subsequently developed clinical vCJD, provide no evidence for maternal transmission of vCJD. However, the number of cases is very small and the incubation period of vCJD, if transmitted from mother to child, is unknown and so the children may yet be too young to have developed symptoms.
11. The phenotype of BSE infection in humans expressing PrP genotypes other than M/M at codon 129 is not known. Given recently published studies in mice expressing the human PrP gene (ref. 2), which suggest that the human PrP genotype may affect disease phenotype, the committee considered it very important that undiagnosed neurological diseases be carefully monitored. In this respect, amongst others, it is recommended that the careful monitoring of neurological illnesses through the PIND surveillance of children (ref. 3) continue.
Conclusions
12. In summary, there is currently no epidemiological evidence for maternal transmission of vCJD, including transmission via breast milk. However, there is a hypothetical risk. Although available evidence is limited and mostly indirect rather than direct, this risk, if any, appears to be low. As a risk cannot be excluded, a watching brief should be maintained.
References:
(1) Tamai Y et al. Demonstration of the transmissible agent in tissue from a pregnant woman with CJD. New Eng J Med 1992 327, 649.
(2) Wadsworth et al. Human prion protein with valine 129 prevents expression of variant CJD phenotype. Science. 2004 306, 1793-1796.
(3) Devereux G et al. Variations in neurodegenerative disease across the UK: findings from the national study of Progressive Intellectual and Neurological Deterioration (PIND). Arch DisChild. 2004 89, 8-12.
-- Terry S. Singeltary Sr. flounder@wt.net
****** [7] Date: Wed 9 Feb 2005 From: ProMED-mail
Removing prions that cause mad cow in humans from blood
Assessing the risk of potential exposure to variant Creutzfeldt-Jakob Disease (vCJD), the human form of 'mad cow disease', from blood transfusion was the focus of the Food & Drug Administration (FDA) Transmissible Spongiform Encephalopathies (TSEs) Advisory Committee in Silver Spring, Maryland today. In response to the Committee's encouragement that new technologies should be considered that might lead to greater reduction of risk while not deferring many donors unnecessarily, Pall Corporation presented the latest scientific data on its new prion reduction technology.
The Leukotrap Affinity Prion Reduction Filter, expected to be launched commercially in Europe this spring, removes infectious prions from red cells, the most widely transfused blood component. Prions are associated with causing vCJD and other fatal neurodegenerative diseases, known as TSEs.
Sam Coker PhD, Principal Scientist and Technical Director of Pall Medical, acknowledged the public health community's heightened concern about the possibility of a 2nd wave of mad cow disease in humans of unknown magnitude globally, including North America. Japan is the latest nation to confirm a human case of mad cow disease.
The Pall Leukotrap Affinity Prion Reduction Filter was developed in response to these problems as part of the Company's mission to help ensure safety of the blood supply. It can remove leukocytes and all types of prions -- both cell and non cell-associated -- from blood prior to transfusion in a single step. Dr. Coker presented an overview of the key study results that show that the novel technology concurrently reduces leukocytes and prions with a 99 percent reduction of the infectious agent. He concluded that the new filter could be used to remove different strains of infectious prions, including those that cause vCJD.
He reviewed a study that found that the new filter reduces the human form of vCJD prions from red cells below the limit of detection of the western blot assay, the gold standard of prion detection. He also discussed a study with the infectious scrapie prion that causes disease in sheep, which showed that the new filter removed all the infectious prions below the limit of detection of the western blot assay.
Dr. Coker described in detail an animal infectivity study comparing filtered and unfiltered blood infected with scrapie prion. After the 300-day study, 3 of the 18 control hamsters that received the unfiltered blood developed scrapie. Only 2 of these animals had displayed clinical signs of the disease. None of the hamsters receiving filtered blood developed scrapie.
[ProMED-mail has no commercial or other association with Pall Medical. The information is relayed in the public interest. - Mod.CP]
ProMED-mail promed@promedmail.org
=================================
Something I submitted to GUT previously;
Subject: Re: gutjnl_el;21 Terry S. Singeltary Sr. (3 Jun 2002) "CJDs (all human TSEs) and Endoscopy Equipment"
Date: Thu, 20 Jun 2002 16:19:51 -0700
From: "Terry S. Singeltary Sr."
To: Professor Michael Farthing
CC: lcamp@BMJgroup.com
References: <001501c21099 c58d182="c58d182" c8bc620="c8bc620" mfacdean1.cent.gla.ac.uk="mfacdean1.cent.gla.ac.uk">
Greetings again Professor Farthing and BMJ,
I was curious why my small rebuttal of the article described below was not listed in this month's journal of GUT? I had thought it was going to be published, but I do not have full text access. Will it be published in the future? Regardless, I thought would pass on a more lengthy rebuttal of mine on this topic, vCJD vs sCJDs and endoscopy equipment. I don't expect it to be published, but thought you might find it interesting, i hope you don't mind and hope to hear back from someone on the questions I posed...
Here is my short submission I speak of, lengthy one to follow below that:
Date submitted: 3 Jun 2002 >>
eLetter ID: gutjnl_el;21 >>
>> Gut eLetter for Bramble and Ironside 50 (6): 888 >>
>>Name: Terry S. Singeltary Sr.
>>Email: flounder@wt.net
>>Title/position: disabled {neck injury}
>>Place of work: CJD WATCH
>>IP address: 216.119.162.85
>>Hostname: 216-119-162-85.ipset44.wt.net
>>Browser: Mozilla/5.0 (Windows; U; Win98; en-US; rv:0.9.4)
>>Gecko/20011019 Netscape6/6.2 >>
>>Parent ID: 50/6/888
>>Citation:
>> Creutzfeldt-Jakob disease: implications for gastroenterology
>> M G Bramble and J W Ironside
>> Gut 2002; 50: 888-890 (Occasional viewpoint)
>> http://www.gutjnl.com/cgi/content/abstract/50/6/888
>> http://www.gutjnl.com/cgi/content/full/50/6/888
>>-----------------------------------------------------------------
>>"CJDs (all human TSEs) and Endoscopy Equipment"
>>----------------------------------------------------------------- >>
>> >>
>>
>> Creutzfeldt-Jakob disease: implications for gastroenterology >>
>> I belong to several support groups for victims and relatives
>>of CJDs. Several years ago, I did a survey regarding
>>endoscopy equipment and how many victims of CJDs have
>>had any type of this procedure done. To my surprise, many
>>victims had some kind of endoscopy work done on them.
>>As this may not be a smoking gun, I think it should
>>warrant a 'red flag' of sorts, especially since data now
>>suggests a substantial TSE infectivity in the gut wall
>>of species infected with TSEs. If such transmissions
>>occur, the ramifications of spreading TSEs from
>>endoscopy equipment to the general public would be
>>horrible, and could potential amplify the transmission
>>of TSEs through other surgical procedures in that
>>persons life, due to long incubation and sub-clinical
>>infection. Science to date, has well established
>>transmission of sporadic CJDs with medical/surgical
>>procedures.
Terry S. Singeltary Sr. >>CJD WATCH
Again, many thanks, Kindest regards,
Terry S. Singeltary Sr. P.O. Box 42 Bacliff, Texas USA 77518 flounder@wt.net CJD WATCH
[scroll down past article for my comments]
Subject: Creutzfeldt-Jakob disease: implications for gastroenterology & CJD 38 years after _diagnostic_ use of hGH (Iatrogenic CJDs & sporadic CJDs)
Date: Mon, 17 Jun 2002 16:46:46 -0700
From: "Terry S. Singeltary Sr."
Reply-To: Bovine Spongiform Encephalopathy
To: BSE-L@uni-karlsruhe.de
Bovine Spongiform Encephalopathy
OCCASIONAL VIEWPOINTS
Creutzfeldt-Jakob disease' implications for gastroenterology
M G Bramble, J W Ironside
Gut 2002;50:888-890
The current clinical views regarding variant Creutzfeldt-Jakob disease, and in particular transmission via endoscopy, of those representing both gastroenterology and the Spongiform Encephalopathy Advisory Committee are presented in an attempt to guide clinicians as to "best practice" given the current state of our knowledge.
See end of article for authors' affiliations
Correspondence to: Professor MG Bramble, Endoscopy Centre, James Cook University Hospital, Marton Rd, Middlesbrough TS4 3BN, UK;
Most gastroenterologists working in the UK have been aware for some time that endoscopy may be a vector for the transmission of prions from a patient incubating, but not clinically manifesting, variant Creutzfeldt-Jakob disease (vCJD) to the next individuals undergoing the same procedure on the same list. To date there are no recorded cases of iatrogenic transmission of vCJD via endoscopy but it remains a risk which will be present for many years to come. Advice to health authorities on individual cases is through the CJD Incidents Panel. However, we are aware that advice to health professionals performing endoscopy needs to be as comprehensive as current evidence will allow, without making it impossible to perform endoscopic procedures on patients who will clearly derive long term health benefits from an accurate endoscopic diagnosis and/or treatment. This article represents the current clinical views of those representing both gastroenterology and the Spongiform Encephalopathy Advisory Com-mittee (SEAC). Both authors sit on the CJD Inci-dents Panel and have been advising the Depart-ment of Health on individual cases during the last year. It is important to note that the advice given in this article may be superseded if additional information or evidence becomes available.
CJD is a member of a group of neurological disorders known as the transmissible spongilorm encephalopathies or prion diseases, which affect both animals (such as scrapie in sheep or bovine spongiform encephalopathy (BSE) in cows) and humans. The precise nature of the transmissible agents responsible for these disorders is unknown but there is increasing evidence to support the prion hypothesis, which states that the agent is composed of an abnormally folded form of a host encoded protein, prion protein. The normal prion protein (PrPc) is expressed in many tissues but occurs at the highest levels in neurones in the central nervous system (CNS) where it may act as a copper binding protein, although its precise physiological role is unknown. The abnormal form of the protein (PrPSc) accumulates in the CNS in prion diseases; the infectious agent is remarkably resistant to most forms of degradation. The association between PrPSc and the gut has been eloquently described in a previous lead-ing article1 and gastroenterologists need to understand where we are in terms of our present day knowledge of this entity.
In humans, prion diseases occur in three major categories: sporadic, acquired, and familial. All are currently untreatable and universally fatal although recent studies have indicated that a combination of drugs may be effective in experimental prion diseases2: this approach is under consideration as a clinical trial. The sporadic form of CJD affects approximately one person per mil-lion per annum in the population on a worldwide basis. CJD has also occurred as an acquired iatrogenic disorder, transmitted to other humans through direct (inadvertent) inoculation of the brain via contaminated neurosurgical instruments, via corneal and dura mater grafts, or through administration of human pituitary ex-tracts used to treat growth hormone or gonadotrophin deficiency. Variant CJD (vCJD) is a new acquired form of CJD which was first reported in 1996 affecting mainly young adults and with a unique neuropathological phenotype.3 It is now widely accepted that bovine prions passed into the human population through consumption of BSE infected bovine tissues; the transmissible agent responsible for vCJD is identical to the BSE agent (but different from the agent in sporadic CJD). The incubation period for vCJD is likely to be lengthy and may have a mean value of 10-30 years. During this time the affected person has the potential to transmit the disease to others via surgical procedures which might result in the transfer of infected tissue into the next person operated on with the same surgical instruments.
The distribution of PrPSc in the body is different in sporadic and variant CJD, reflecting the differ-ent pathogenesis of the two forms. In the case ot sporadic CJD, prion infectivity is largely limited to the CNS (including the retina) and only opera-tions involving the brain and eye have resulted in iatrogenic transmission of the disease. Gastro-intestinal endoscopy is unlikely to be a vector for the transmission of sporadic CJD as infected tissue is not encountered during the procedure. No special precautions are necessary during or after the procedure and the endoscope should be cleaned and disinfected in the normal thorough way.4
"Endoscopy on patients who are incubating vCJD may result in exposure of the instrument (and particularly the biopsy forceps) to PrPsc''
In contrast, in vCJD the lymphoreticular system throughout the body contains PrPSc at the time of death, and experimental evidence suggests that the lymphoreticular system may contain significant levels of infectivity for most of the incuba-tion period.5 To support this, in vCJD abnormal prion protein was found in the germinal centres in the wall of an appendix from a vCJD patient that was removed eight months before the onset of neurological disease.6 As lymphoid follicles and germinal centres are widely distributed in the gastrointestinal tract (and are often biopsied), it is possible that endoscopy on patients who are incubating vCJD may result in exposure of the instrument (and particularly the biopsy forceps) to PrPsc. Consequently, the question now arises, how great is the risk of secondary (person to person) transmission in endoscoping a patient incubating vCJD? There are three scenarios which gastroenterologists are likely to encounter and this editorial will attempt to guide clinicians as to "best practice" given the current state of our knowledge.
UPPER GASTROINTESTINAL ENDOSCOPY
Scenario No 1
Occasionally gastroenterologists may be requested to endo-scope a patient with known or probable sporadic CJD (usually to site a PEG feeding tube). This can be carried out in the rou-tine way provided vCJD is not suspected. If inadvertently a patient with suspected vCJD is endoscoped, the instrument used should be quarantined until the postmortem diagnosis is known. If sporadic CJD is diagnosed, the endoscope can be returned to use following thorough cleaning and decontami-nation, as is normal practice. If vCJD is diagnosed the endoscope cannot be used again and should be quarantined or sent to the National CJD Surveillance Unit in Edinburgh for research purposes. The previous advice to destroy such instru-ments represents a lost opportunity to study the risks involved in more detail. It would also be good practice to inform colleagues locally that a quarantined instrument was available for use in other endoscopy units if they too had a patient with suspected vCJD requiring endoscopy.
Scenario No 2
For patients with known or probable vCJD,7 endoscopy should only be a last resort. Ultrasound guided insertion of a gastrostomy feeding tube would be preferable to a PEG feeding tube if local expertise is available. If not, endoscopy should be per-formed using an instrument already set aside for such patients. If no such instrument is available locally, one can be loaned to any hospital by the National CJD Surveillance Unit in Edinburgh (contact telephone number 0131 537 1980). If scenario No 2 becomes more common, endoscopes may need to be held regionally for this purpose.
Scenario No 3
This scenario covers patients who have been endoscoped by an instrument previously used on a patient who was not known to be incubating vCJD at the time of endoscopy but who sub-sequently went on to develop the disease. This could become the commonest scenario and it must be assumed that the patient who went on to develop vCJD was incubating the dis-ease at the time of the original endoscopy. This also means that infectious material may not have been removed completely by current methods of decontaminating endoscopes, and that subsequent patients have been exposed to the prion agent. The instrument used should therefore be quaran-tined until advice has been sought from the CJD Incidents Panel (Department of Health, Skipton House, London; contact telephone 0207 972 1761) as to the management of the situa-tion. Local infection control teams will need to be involved with contact tracing and information handling.
LOWER GASTROINTESTINAL ENDOSCOPY
It is unlikely that colonoscopy would be clinically justifiable in a patient known or strongly suspected as suffering from vCJD. However, it is quite possible that an asymptomatic patient incubating vCJD may undergo colonoscopy prior to diagnosis and this situation is essentially the same as in scenario 3. The risks of transmitting prion protein to the next patient are much greater however, due to a number of factors which relate to the amount of lymphatic tissue encountered during endos-copy and the number, site, and size of mucosal biopsies obtained by this method.
In general the risks of transmitting vCJD from one patient to another are dependent on the infectivity of the tissues involved, the amount of tissue contaminating the instrument, the effectiveness of the decontamination processes, and the susceptibility of subsequently exposed patients. Experimental studies suggest that levels of infectivity in prion diseases are highest in the CNS and retina, which are approximately two logs higher than in the tonsils and other lymphoreticular tis-sue. A recent study has also detected the abnormal form of the prion protein in rectal tissue from a patient with vCJD by western blot examination of autopsy tissues.8 The risk of transmitting vCJD through the endoscopy procedure itself is likely to be small, but contamination of the endoscope and forceps as a result of biopsy of lymphoid tissues may represent a larger (but currently unquantifiable) risk, even though only small amounts of tissue are involved.
"The risks of transmitting vCJD from one patient to another are dependent on the infectivity of the tissues involved, the amount of tissue contaminating the instrument, the effectiveness of the decontamination processes, and the susceptibility of subsequently exposed patients"
The greatest risk is undoubtedly that which ensues from biopsy of the terminal ileum where Peyer's patches may con-tain significant levels of prion protein for a patient incubating vCJD. The biopsy forceps and the colonoscope become poten-tial vectors for disease transmission under these circum-stances. Meticulous manual cleaning of the colonoscope is probably the best defence against person to person transmis-sion. The same is true of the biopsy forceps, but as disposable forceps are now available there is a strong argument for mov-ing towards the universal use of disposable biopsy forceps for mucosal samples taken at colonoscopy. Endoscopy units should now work towards a policy of using disposable biopsy forceps as the only practical way of minimising the risk which results from ileal biopsy. In addition, "random" biopsies should be kept to a minimum as lymphoid tissue is distributed widely throughout the gastrointestinal tract. Although thor-ough cleaning of flexible endoscopes ensures patient safety for "normal" pathogens, the same process may not be adequate for the PrPsc. The main benefit of the decontamination process under these circumstances is undoubtedly effective manual cleaning, as glutaraldehyde may stabilise PrPSc on the metal surface of the endoscope, with potentially adverse conse-quences. It follows that brushes used to clean the channels of the endoscope are used only once to ensure maximum efficiency and biopsy forceps should also be functioning opti-mally and discarded as soon as they appear to be under performing (tearing tissue rather than cutting it). The rubber valve protecting the biopsy channel is another item which is potentially disposable and serious consideration should be given to single use valves. Again, more research is required to determine "best practice". For rigid endoscopes, autoclaving at the recommended conditions for CJD9 is the best way of attempting decontamination.
What should endoscopists do in the short term? The answer to this question must be to ensure as far as possible that manual cleaning of endoscopes and reuseable accessories is of the highest standard. Endoscopy has a major role in patient care, and this should not be compromised unless it is absolutely unavoidable in the public interest. It is also essen-tial that endoscopes should be individually identifiable and their use traceable in any given patient population. Random biopsies should be kept to an absolute minimum (particularly of the ileum in colonoscopy) and endoscopy itself should be as atraumatic as possible, especially gastroscopy where the instrument is in contact with the mucosa covering the tonsils. Biopsy forceps should be treated as "high risk" and undergo thorough ultrasonic cleaning followed by autoclaving. As research in the UK progresses, it is likely that other procedures will be developed to inactivate prion infectivity and to remove proteins from instrument surfaces. The development of such techniques (along with more sensitive tests for prion detection) may well have an impact on future advice concern-ing endoscopy and CJD.
Depending on the final numbers of people infected with vCJD, we must assume that a significant number may undergo endoscopy before neurological symptoms appear10. It is there-fore up to every endoscopist to be aware of the dangers and follow the advice set out here. Further advice on specific cases and possible exposure incidents can be obtained from the CJD Incidents Panel (Department of Health, Skipton House, London; contact telephone 0207 972 1761).
Authors' affiliations M G Bramble, Endoscopy Centre, James Cook University Hospital, Marton Road, Middlesbrough TS4 3BW, UK J W Ironside, CJD Surveillance Unit, Western General Hospital, Crewe Road, Edinburgh EH4 2XU, UK
mike.bramble@stees.nhs.uk
Accepted for publication 19 November 2001
REFERENCES
1 Shmakov AN, Ghosh S. Prion proteins and the gut: une liaison dangereuse? Gut 2001;48:443-7.
2 Korth C, May BCH, Cohen FE, et al. Acridine and phenothiazine derivatives as pharmacotherapeutics for prion disease. Proc Nail Acad Sci USA 2001;98:9836-41.
3 Will RG, Ironside JW, Zeidler M, et al. A new variant of Creutzfeldt-Jakob disease in the UK. Lancet 1996;347:921-5.
4 Report of a Working Party of the British Society of Gastroenterology Endoscopy Committee. Cleaning and disinfection of equipment for gastrointestinal endoscopy. Gut 1998;42:585-93.
5 Hill AF, Butterworth R J, Joiner S, et al. Investigation of variant Creutzfeldt-Jacob disease and other human prion diseases with tonsil biopsy samples. Lancet 1999;353:183-9.
6 Hilton DA, Fathers E, Edwards P, et al. Prion immunoreactivity in the appendix before the clinical onset of new variant Creutzfeldt-Jacob disease. Lancet 1998;352:703-4.
7 Will RG, Zeidler M, Stewart GE, et al. Diagnosis of new variant Creutzfeldt-Jakob disease. Ann Neuro12000;47:575-82.
8 Wadsworth JD, Joiner S, Hill AF, et al. Tissue distribution of protease resistant prion protein in variant Creutxfleldt-Jakob disease using a highly sensitive immunoblotting assay. Lancet 2001 ;358:171-80.
9 Dangerous Pathogens Spongiform Encephalopathy Advisory Committee. Transmissible spongiform encephalopathy agents: safe working and the prevention of infection. London: The Stationary Office, 1998.
10 Ironside JW, Hilton DA, Ghani A, et al. Retrospective study of prion protein accumulation in tonsil and appendix tissue. Lancet 2000;355:1693-94.
http://www.gutjnl.com/cgi/content/abstract/50/6/888
========================================================
Greetings List Members,
This is _very_ disturbing to me:
snip...
The distribution of PrPSc in the body is different in sporadic and variant CJD, reflecting the different pathogenesis of the two forms. In the case ot sporadic CJD, prion infectivity is largely limited to the CNS (including the retina) and only operations involving the brain and eye have resulted in iatrogenic transmission of the disease. Gastro-intestinal endoscopy is unlikely to be a vector for the transmission of sporadic CJD as infected tissue is not encountered during the procedure. No special precautions are necessary during or after the procedure and the endoscope should be cleaned and disinfected in the normal thorough way.4
snip...
i personally believe it is irresponsible for anyone to state in this day and time, that sporadic CJDs (now at 6 variants) will not transmit the disease by this route. considering infective dose cannot be quantified, only speculated, such a statement is thus, irresponsible. to hypothosize that sporadic CJD just happens spontaneously (with no scientific proof), that the PrPSc distribution in tissues of all sporadic CJDs is entirely different than that of vCJD, without being able to quantify the titre of infection, or even confirm all the different variants yet, again is _not_ based on all scientific data, then it's only a hypothosis. who is to say that some of these variants of sporadic CJD were not obtained _orally_?
also stated:
snip...
Although thorough cleaning of flexible endoscopes ensures patient safety for ''normal'' pathogens, the same process may not be adequate for the PrPSc.
snip...
The sporadic form of CJD affects approximately one person per mil-lion per annum in the population on a worldwide basis.
who is to say how much infectivity are in some of these variants of sporadic CJDs, without confirming this? if we look at the 6 different variants of sporadic CJDs, has the infective dose for all 6 _documented_ variants been quantified, and documented as being 'measurable'?
will there be more variants of sporadic CJDs, and what of the ramifications from them?
what of other strains/variants of TSE in cattle, BSE in sheep, CWD in cattle, or any of the 20+ strains of Scrapies in deer/elk? i get dizzy thinking of the different scenerio's. what would the human TSEs from these species look like and how can anyone quantify any tissue infectivity from these potential TSE transmissions to humans, and the risk scenerio described here from this potential route? could not some of these sporadic CJDs have derived directly or indirectly from one of these species, and if so, pose a risk by the route described here?
something else to consider, in the recent finding of the incubation period of 38 years from a _small_ dose of human growth hormone;
snip...
We describe the second patient with hGH related CJD in the Netherlands. The patient developed the disease 38 years after hGH injections. To our knowledge, this is the longest incubation period described for any form of iatrogentic CJD. Furthermore, our patient was _not_ treated with hGH, but only received a _low_ dose as part of a diagnostic procedure. (see full text below).
snip...
so my quesion is, how low is 'low' in quantifing the infectious dose in vCJD, comparing to _all_ sporadic CJDs, from the different potential routes, sources, and infectivity dose?
will the titre of infectivity in every tissue and organ of all sporadic CJDs stay exact or constant, no matter what the infective dose, route and species may be? this is considering you don't buy the fact that sporadic CJDs 85%+ of _all_ CJDs, are a happen stance of bad luck, happen spontaneously without cause, and are one-in-a-million world wide, with no substantial surveillance to confirm this.
Diagnosis and Reporting of Creutzfeldt-Jakob Disease T. S. Singeltary, Sr; D. E. Kraemer; R. V. Gibbons, R. C. Holman, E. D. Belay, L. B. Schonberger
http://jama.ama-assn.org/issues/v285n6/ffull/jlt0214-2.html
and what of Dr. Prusiner et al recent work about tissue infectivity;
Prions in skeletal muscle
snip...
Our data demonstrate that factors in addition to the amount of PrP expressed determine the tropism of prions for certain tissues. That some muscles are intrinsically capable of accumulating substantial titers of prions is of particular concern. Because significant dietary exposure to prions might occur through the consumption of meat, even if it is largely free of neural and lymphatic tissue, a comprehensive effort to map the distribution of prions in the muscle of infected livestock is needed. Furthermore, muscle may provide a readily biopsied tissue from which to diagnose prion disease in asymptomatic animals and even humans.
snip...
http://www.pnas.org/
can the science/diagnostic measures used to date, measure this, and at the same time guarantee that no titre of infectivity exists from sporadic CJDs (all of the variants), from this potential mode and route of transmission?
i don't think so, this is just my opinion. this is why i get paid nothing, and these scientists get the big bucks. i just hope i am wrong and the big bucks are correct in their _hypothisis_ of this potential mode/route of transmission with endoscopy equipment, from _all_ human TSEs.
i understand we have to weigh the risks of what we know to what we don't know, to the disease we _may_ catch to what we are having the procedure for, but to categorically state at this present time of scientific knowledge;
snip...
"Gastro-intestinal endoscopy is unlikely to be a vector for the transmission of sporadic CJD as infected tissue is not encountered during the procedure. No special precautions are necessary during or after the procedure and the endoscope should be cleaned and disinfected in the normal thorough way.4"
snip...
but, to categorically state this, in my opinion, is not only wrong, but potentially very dangerous to the future of human health...TSS
SHORT REPORT
Creutzfeldt-Jakob disease 38 years after diagnostic use of human growth hormone
E A Croes, G Roks, G H Jansen, P C G Nijssen, C M van Duijn
...............................................................
J Neurol Neurosurg Psychiatry 2002;72:792-793
A 47 year old man is described who developed pathology proven Creutzfeldt-Jakob disease (CJD) 38 years after receiving a low dose of human derived growth hormone (hGH) as part of a diagnostic procedure. The patient presented with a cerebellar syndrome, which is compatible with iatrogenic CJD. This is the longest incubation period described so far for iatrogenic CJD. Furthermore, this is the first report of CJD after diagnostic use of hGH. Since the patient was one of the first in the world to receive hGH, other cases of iatrogenic CJD can be expected in the coming years.
Prion diseases are potentially transmissible. Human to human transmission was first reported in 1974, when a 55 year old woman was described who developed symptoms of Creutzfeldt-Jakob disease (CJD) 18 months after a corneal transplant.1 Since then, transmission has been reported after stereotactic electroencephalographic (EEG) depth recording, human growth hormone (hGH) and gonadotrophin treatment, and dura mater transplantation.2-5 More than 267 patients with iatrogenic CJD are known today and their number is growing.6 The most important iatrogenic cause of CJD is still contaminated cadaveric hGH. Exposure to contaminated hGH occurred before 1985, when recombinant growth hormone became available. In a recent study, incubation periods in 139 patients with hGH associated CJD were found to range from 5-30 years, with a median of 12 years.6 One of the factors influencing incubation time is genotype on polymorphic codon 129 of the prion protein gene.7 The incubation time is significantly shorter in people who are homozygous for either methionine or valine on this polymorphism.7
We describe the second patient with hGH related CJD in the Netherlands. The patient developed the disease 38 years after hGH injections. To our knowledge, this is the longest incubation period described for any form of iatrogenic CJD. Further-more, our patient was not treated with hGH but only received a low dose as part of a diagnostic procedure.
CASE REPORT
This patient presented at the age of 47 years with paraesthesia in both arms for six months, difficulty with walking for four weeks, and involuntary movements of mainly the upper extremities of two weeks' duration. He did not notice any change in cognitive function, although his twin sister had noticed minor memory disturbances. There was no family history of neurological disease. During childhood the patient had experienced a growth delay compared with his twin sister and with the average in the Netherlands. When he was 9 years old, a nitrogen retention test with 6 IU hGH over five days was performed to exclude growth hormone deficiency. Since the result was not decisive, a quantitative amino acid test was performed, which measures 30 amino acids during fasting and one, two, and three hours after growth hormone injection. No abnormal amino acid concentrations were found making the diagnosis of primordial dwarfism most likely. Therefore, no treatment with hGH was given.
On neurological examination we found a slight dysarthria without aphasia. Cranial nerve function was normal. Walking was unstable and wide based. During movements of the upper extremities myoclonic jerks were present. Sensation, muscle tone, and strength were normal. Co-ordination was impaired in all four limbs with a disturbed balance. Tendon reflexes were brisk at the arms and increased at the legs with a clonus in the ankle reflex. Plantar responses were both normal. On the mini mental state examination, the patient scored 30/30. Routine laboratory investigation, thyroid function, vitamin concentrations (B-1, B-6, B-12, and E), and copper metabolism were normal. Admission EEG examination showed generalised arrhythmic slow activity with diffuse spikes and spike waves. EEG examination two months later showed a further slowing of the rhythm with bilateral diphasic sharp waves but was not typical for CJD. Cerebral magnetic resonance imaging was normal. Cerebrospinal fluid examination showed 1 cell/3 µl, normal glucose and protein concentrations, and a strongly positive 14-3-3 protein test. The patient was homozygous for methionine on the PRNP codon 129 polymorphism. On clinical grounds, CJD was diagnosed. Within one month the patient's condition deteriorated rapidly and because of severe disturbances in coordination and progressive myoclonus he became bedridden. An eye movement disorder developed with slow saccadic and dysmetric eye movements. Temperature became unstable with peaks of 39°C without an infectious focus, for which a disorder of autoregulation was presumed. Until a very advanced stage, cognitive function was intact. The patient died five months after admission. The diagnosis of CJD was confirmed at necropsy. The brain weighed 990 g and showed clear cortical and cerebellar atrophy. Spongiosis, neuronal loss, and gliosis were found predominantly in the putamen, caudate nucleus, and basotemporal and cerebellar cortex; the cerebellum was the most severely affected of these. Vacuoles ranged from 2-12 µm. No amyloid or Kuru plaques were found. Immunohistochemical staining (3F4 antibody 1:1000, Senetek, USA) was clearly positive for prion protein accumulation in a "synaptic" distribution. Most deposition was found in the stratum moleculare of the cerebellum.
DISCUSSION
We describe a 47 year old patient who developed pathology proven CJD 38 years after hGH injections. The patient was never treated with hGH but received a small dose as part of a diagnostic procedure. The onset of CJD was signalled by prodromal symptoms of paraesthesia followed by a rapidly progressive ataxia. The disease presentation and course with predominantly cerebellar and eye movement disorders are compatible with iatrogenic CJD caused by hGH treatment.6 8
Growth hormone treatment was first described in 1958 but hGH was not produced on a larger scale from human pituitary glands until the beginning of the 1960s. In the Netherlands growth hormone extraction started in 1963 and was soon centrally coordinated. Until 1979 growth hormone was extracted non-commercially from pituitaries by a pharmaceutical company. In 1971 commercial products also became available. Our patient was one of the first to receive hGH in the Netherlands but the origin of this product was not recorded. A causal relation can therefore not be established with full certainty, but coincidentally receiving growth hormone and developing this very rare disease is unlikely. Since the clinical course in this relatively young patient is in accordance with an iatrogenic cause, we think the probability is high that the hGH injections explain the development of CJD in this patient.
The first Dutch patient with hGH related CJD died in 1990. 9 During several periods from 1963 to 1969 she received intramuscular injections of hGH. During an unknown period the hGH was derived from South America. At age 39, 27 years after starting the treatment, she developed an ataxic gait, slurred speech, sensory disorders, and myoclonus, but her cognitive function remained normal. Postmortem examination of the brain confirmed the diagnosis of CJD.9 Following the identification of this patient, a retrospective study was started to trace all 564 registered hGH recipients who were treated before May 1985. Until January 1995, none of these was suspected of having CJD.10 Since 1993 prospective surveillance for all forms of human prion disease has been carried out in the Netherlands and, apart from the patient described above, a further two patients with iatrogenic CJD have been identified, who developed the disease after dura mater transplantation.11
An incubation period as long as 38 years had never been reported for iatrogenic CJD. Huillard d'Aignaux et al7 studied the incubation period in 55 patients with hGH related CJD in a cohort of 1361 French hGH recipients. The median incubation period was between 9 and 10 years. Under the most pessimistic model, the upper limit of the 95% confidence interval varied between 17 and 20 years. Although the infecting dose cannot be quantified, it can be speculated that the long incubation period in our patient is partly explained by the administration of a limited amount of hGH. This hypothesis is supported by experimental models, in which higher infecting doses usually produce shorter incubation periods.6 Since our patient was one of the first in the world to receive hGH, this case indicates that still more patients with iatrogenic CJD can be expected in the coming years. Another implication of our study is that CJD can develop even after a low dose of hGH. This case once more testifies that worldwide close monitoring of any form of iatrogenic CJD is mandatory.
ACKNOWLEDGEMENTS
We are grateful to M Jansen PhD MD for his search for the origin of the growth hormone and P P Taminiau MD. CJD surveillance in the Netherlands is carried out as part of the EU Concerted Action on the Epidemiology of CJD and the the EU Concerted Action on Neuropathology of CJD, both funded through the BIOMED II programme, and is supported by the Dutch Ministry of Health. This surveillance would not have been possible without the cooperation of all Dutch neurologists and geriatricians.
........................................
Authors' affiliations
E A Croes, G Roks*, C M van Duijn, Genetic Epidemiology Unit, Department of Epidemiology and Biostatistics, Erasmus University Medical Centre Rotterdam, PO Box 1738, 3000 DR Rotterdam, Netherlands
P C G Nijssen, Department of Neurology, St Elisabeth Hospital, PO Box 90151, 5000 LC Tilburg, Netherlands
G H Jansen, Department of Pathology, University Medical Centre Utrecht, Heidelberglaan 100, 3584 CX Utrecht, Netherlands
*Also the Department of Neurology, St Elisabeth Hospital
Correspondence to: Professor C M van Duijn, Genetic Epidemiology Unit, Department of Epidemiology and Biostatistics, Erasmus University Medical Centre Rotterdam, PO Box 1738, 3000 DR Rotterdam, Netherlands; vanduijn@epib.fgg.eur.nl
Received 27 December 2001 In revised form 1 March 2002 Accepted 12 March 2002
Competing interests: none declared
REFERENCES
1 Duffy P, Wolf J, Collins G, et al. Possible person-to-person transmission of Creutzfeldt-Jakob disease. N Engl J Med 1974;290:692-3.
2 Bernoulli C, Siegfried J, Baumgartner G, et al. Danger of accidental person-to-person transmission of Creutzfeldt-Jakob disease by surgery. Lancet 1977;i:478-9.
3 Koch TK, Berg BO, De Armond SJ, et al. Creutzfeldt-Jakob disease in a young adult with idiopathic hypopituitarism: possible relation to the administration of cadaveric human growth hormone. N Engl J Med 1985;313:731-3.
4 Cochius JI, Burns RJ, Blumbergs PC, et al. Creutzfeldt-Jakob disease in a recipient of human pituitary-derived gonadotrophin. Aust NZ J Med 1990;20:592-3.
5 Thadani V, Penar PL, Partington J, et al. Creutzfeldt-Jakob disease probably acquired from a cadaveric dura mater graft: case report. J Neurosurg 1988;69:766-9.
6 Brown P, Preece M, Brandel JP, et al. Iatrogenic Creutzfeldt-Jakob disease at the millennium. Neurology 2000;55:1075-81.
7 Huillard d'Aignaux J, Costagliola D, Maccario J, et al. Incubation period of Creutzfeldt-Jakob disease in human growth hormone recipients in France. Neurology 1999;53:1197-201.
8 Billette de Villemeur T, Deslys JP, Pradel A, et al. Creutzfeldt-Jakob disease from contaminated growth hormone extracts in France. Neurology 1996;47:690-5.
9 Roos RA, Wintzen AR, Will RG, et al. Een patiënt met de ziekte van Creutzfeldt-Jakob na behandeling met humaan groeihormoon. Ned Tijdschr Geneeskd 1996;140:1190-3.
10 Wientjens DP, Rikken B, Wit JM, et al. A nationwide cohort study on Creutzfeldt-Jakob disease among human growth hormone recipients. Neuroepidemiology 2000;19:201-5.
11 Croes EA, Jansen GH, Lemstra AF, et al. The first two patients with dura mater associated Creutzfeldt-Jakob disease in the Netherlands. J Neurol 2001;248:877-81.
re-CJD after diagnostic use of human growth hormone
from a donor sourcing aspect, seems the record keeping here has a lot to be desired for, let us hope it has improved for recipients sake.
also, they speak of 'low dose fitting long incubation'. what about KURU still existing after some 40 years exposure had ceased. i don't believe in most instances the dose with kuru is low. just something else to ponder?
TSS
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12023427&dopt=Abstract
1: Ann Neurol 1999 Aug;46(2):224-33
Classification of sporadic Creutzfeldt-Jakob disease based on molecular and phenotypic analysis of 300 subjects.
Division of Neuropathology, Institute of Pathology, Case Western Reserve University, Cleveland, OH 44106, USA.
snip...
The present data demonstrate the existence of six phenotypic variants of sCJD. The physicochemical properties of PrP(Sc) in conjunction with the PRNP codon 129 genotype largely determine this phenotypic variability, and allow a molecular classification of the disease variants.
snip...
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=10443888&dopt=Abstract
were not all CJDs, even nvCJD, just sporadic, until proven otherwise?
Terry S. Singeltary Sr., P.O. BOX 42, Bacliff, Texas 77518 USA
http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html
Professor Michael Farthing wrote:
Louise Send this to Bramble (author) for a comment before we post. Michael
=======================================================
SEE FULL TEXT ;
Subj: Reprocessing of Flexible Endoscopes and Endoscopic Accessories - an International Comparison of Guidelines
Date: 9/17/02 3:28:43 AM Eastern Daylight Time
From: flounder@WT.NET (Terry S. Singeltary Sr.)
Sender: BSE-L@UNI-KARLSRUHE.DE (Bovine Spongiform Encephalopathy)
Reply-to: BSE-L@UNI-KARLSRUHE.DE (Bovine Spongiform Encephalopathy)
To: BSE-L@UNI-KARLSRUHE.DE
Bovine Spongiform Encephalopathy
Reprocessing of Flexible Endoscopes and Endoscopic Accessories - an International Comparison of Guidelines
Zeitschrift für Gastroenterologie
© Georg Thieme Verlag Stuttgart New York More about this journal
Endoscopic examinations and procedures are essential for diagnosis and treatment of gastrointestinal diseases. As a result of poor reprocessing practice microorganisms can be transmitted via endoscope. The majority of infection transmissions is due to insufficient performance of cleaning and disinfection disregarding guidelines of societies of gastrointestinal endoscopy.
A review of the literature and a comparison of European and American guidelines for reprocessing flexible endoscopes are given. Differences in the classification of endoscopic devices, on the possibility of prion transmission, recommendations on staff training and protection, quality assurance of reprocessing and evidence-based graduation of guidelines are stressed and discussed. With respect to the procedure of endoscope reprocessing, differences concerning the cleaning solution to choose, necessity of thoroughly manual cleaning and brushing of the accessible endoscope channels (even in the case of subsequent automatic reprocessing endoscopes in washers-disinfectors), disinfection solution, microbiological quality of water for final rinsing and rationale for alcohol flush of endoscope channels for better drying are mentioned.
The need for experimental investigations of the cleaning and disinfection process is stressed. In contrast to recent guidelines of European and American societies of gastrointestinal endoscopy, the now updated recommendations of the Robert Koch-Institute for reprocessing flexible endoscopes and endoscopic accessories are evidence-based and graduated.
Original Article Z Gastroenterol 2002; 40: 531-542 DOI: 10.1055/s-2002-32807 Table of Contents Leitlinien zur Aufbereitung flexibler Endoskope und endoskopischen Zusatzinstrumentariums im internationalen Vergleich Reprocessing of Flexible Endoscopes and Endoscopic Accessories - an International Comparison of Guidelines O. Leiß1, U. Beilenhoff2, L. Bader3, M. Jung2, M. Exner4 1Fachbereich Gastroenterologie, Deutsche Klinik für Diagnostik, Wiesbaden 2St. Hildegardis-Krankenhaus, Mainz 3Max von Pettenkofer-Institut der LMU München, München 4Hygiene-Institut der Universität Bonn, Bonn
Zusammenfassung
Endoskopische Untersuchungen und Eingriffe sind für Diagnostik und Therapie gastrointestinaler Erkrankungen unverzichtbar. Durch mangelhaft aufbereitete Endoskope können Mikroorganismen übertragen werden. Die Mehrzahl der Infektionsübertragungen bei Endoskopie ist auf unzureichende Reinigungs- und Desinfektionsmaßnahmen unter Missachtung aktueller Aufbereitungsrichtlinien der Fachgesellschaften zurückzuführen.
In einer Literaturübersicht werden die Leitlinien europäischer und amerikanischer Fachgesellschaften zur Aufbereitung flexibler Endoskope verglichen. Es werden Unterschiede in der Klassifikation des endoskopischen Instrumentariums, in der Bewertung der Prionenproblematik, in den Anforderungen an Personalschulung und Personalschutz, in der Betonung qualitätssichernder Maßnahmen und in der wissenschaftlichen Untermauerung und Graduierung der ausgesprochenen Empfehlungen dargestellt und diskutiert. Zu Einzelschritten der Aufbereitung werden Unterschiede hinsichtlich der einzusetzenden Reinigungslösung, der Notwendigkeit einer manuellen Bürstenreinigung der Endoskopkanäle (auch bei nachfolgender maschineller Aufbereitung), der Wahl des Desinfektionsmittels, der mikrobiologischen Qualität des zur Schlussspülung verwendeten Wassers und der Empfehlung einer Spülung der Endoskopkanäle mit Alkohol für eine verbesserte Trocknung herausgestellt und kritisch bewertet.
Es wird offensichtlich, dass experimentelle Untersuchungen zu Einzelaspekten der Endoskop-Aufbereitung weitgehend fehlen bzw. erst in jüngster Zeit bearbeitet wurden. Im Gegensatz zu bisherigen Leitlinien europäischer und amerikanischer Fachgesellschaften zur Endoskop-Aufbereitung sind die aktualisierten Empfehlungen des Robert Koch-Instituts zur Aufbereitung flexibler Endoskope und endoskopischen Zusatzinstrumentariums mit der verfügbaren Evidenz verknüpft und graduiert. Schlüsselwörter
Flexible Endoskope - Aufbereitung - Reinigung - Desinfektion - Personalschulung - Qualitätssicherung - Mikrobiologische Prüfungen - Hygiene Abstract
http://www.thieme-connect.com/DOI/DOI?10.1055/s-2002-32807
TSS
http://mailhost.rz.uni-karlsruhe.de/warc/bse-l.html
SEE FULL TEXT ;
Saturday, January 16, 2010
Evidence For CJD TSE Transmission Via Endoscopes 1-24-3 re-Singeltary to Bramble et al
http://creutzfeldt-jakob-disease.blogspot.com/2010/01/evidence-for-cjd-tse-transmission-via.html
layperson
Terry S. Singeltary Sr.
P.O. Box 42
Bacliff, Texas USA 77518
flounder9@verizon.net