Endoscopy Reprocessing, Infection Control & Operations
JANUARY 9, 2025
Preventing Prion Disease Infection in Endoscopy
Researchers from Mayo Clinic have illustrated a novel way of handling endoscopy procedures in patients suspected to have Creutzfeldt-Jakob disease.
Although the CDC publishes infection control guidelines for CJD, no best practices exist for endoscopy procedures in these patients, investigator Yara Salameh, MD, a postdoctoral research fellow in the Division of Gastroenterology and Hepatology at Mayo Clinic, in Rochester, Minn., told GEN Priority Report.
Dr. Salameh and her team collaborated with other specialists, including infectious disease and surgical reprocessing experts, and experts at the CDC, to develop a comprehensive protocol for the handling and disposing of endoscopes used for a patient suspected to have CJD.
The specific tissue involved in the endoscopy procedure was a huge factor in determining the potential for transmission, reported Dr. Salameh, presenting the findings at ACG 2024 (poster 2387).
Biopsies and procedures that involve neurological tissues are considered high risk for putting equipment in contact with tissues that house prions in an infected person. However, during routine GI procedures—including endoscopic ultrasound, fine-needle aspiration of the lymph nodes or pancreas, and endoscopic retrograde cholangiopancreatography (ERCP) of the liver and liver channels or pancreas—scopes come into contact with tissues that are not likely to harbor prions, Dr. Salameh said. “It’s extremely unlikely that a scope that was used in a routine GI procedure would carry the risk of prion transmission,” she noted.
Nevertheless, she and her co-investigators recommend using a disposable scope in both low- and high-risk procedures and incinerating the scope after the procedure. If disposable scopes are not an option, reusable scopes should be sequestered in a sterilization container and tested for prions. If the scope tests positive, it should be incinerated, and if the test is negative, the scope should undergo full reprocessing.
Dr. Salameh and her co-investigators at Mayo Clinic have not had to use the protocol yet, she said, “but we want to be prepared. When you do encounter an endoscopy patient with CJD, you need to act fast and not take chances with such a scary disease.”
Klaus Mergener, MD, an affiliate professor of medicine at the University of Washington, in Seattle, emphasized that the risk for CJD infection from an endoscopy procedure is rare. A 2020 review found no recorded evidence of endoscope-related CJD infections (J Hosp Infect 2020;104[1]:92-110).
However, Dr. Mergener stressed that endoscopy suites should be prepared. He agreed disposable scopes should be used in these instances, if possible, since endoscopes cannot hold up to most of the sterilization techniques used for other medical equipment.
“There are now FDA-approved disposable GI endoscopes for upper endoscopy, colonoscopy and for ERCP,” he said. “This will cover most clinical situations where urgent endoscopic evaluation of such a patient is needed.”
Although CJD infections are rare—about 600 reported cases in the United States every year—they have been rising in recent years (JAMA Neurol 2024;81[2]:195-197), Dr. Salameh noted, adding, “No matter how rare the disease is, it should be on our minds. People die within a year of getting Creutzfeldt-Jakob disease, and we want to be at a low threshold of suspicion when it comes to CJD.”
—Kaitlin Sullivan
This article is from the December 2024 Priority Report print issue.
Thank You, Thank You, better late than never!
25 years ago or so, I tried warning of the same thing to GUT Journal, they were going to publish it, but then Bramble shot it down. Wonder how many people were needlessly exposed to the cjd the prion since then?
Singeltary on CJD and Endoscopy Risk Factors 1999, nobody listened…terry
TSE Prion and Endoscopy Equipment Singeltary Tue, 12 Oct 1999
TSE Prion and Endoscopy Equipment
Subject: Re: CJD * Olympus Endoscope
Date: Tue, 12 Oct 1999 15:57:03 –0500
From: "Terry S. Singeltary Sr."
To: GOLDSS@...
References: 1
Dear Mr. Goldstine, Hello again, I hope the CDC has not changed your mind, since our phone call, about sending me the information, in which we spoke of. I am still waiting for the information, re-fax. Someone had told me, you would not send me the information, but I told them you would, due to the importance of it pertaining to public safety, and the fact, you are a Doctor. I hope you don't disappoint me, and the rest of the public, and hide the facts, as the CDC and NIH have for years. Olympus can be part of the Truth, or you can be part of the cover-up. We are going to find out, sooner or later.
I already know, as do many more.
Still waiting,
Kind Regards,
Terry S. Singeltary Sr.
Wednesday, March 02, 2016
Endoscope Maker Olympus Agrees To $646 Million Settlement Over Kickbacks, while still ignoring the elephant in the room, CJD TSE PRIONS Health Inc.
*** Evidence For CJD TSE Transmission Via Endoscopes 1-24-3 re-Singeltary to Bramble et al ***
Evidence For CJD/TSE Transmission Via Endoscopes
From Terry S. Singletary
see full text;
Evidence For CJD/TSE Transmission Via Endoscopes
From Terry S. Singletary, Sr flounder@wt.net 1-24-3
I have researched human/animal TSEs now for over 5 years due to the death of my Mother from the Heidenhain Variant Creutzfeldt Jakob disease, one of six - known - variants of the infamous 'sporadic' CJD.
I did a little survey several years ago about CJD and ENDOSCOPY in 2001, and then went there again when another article was released recently. However, they seemed to only be concerned with the vCJD strain and risk from endoscopy equipment.
My concerns are if vCJD can be transmitted by blood, and there are now 6 variants of the infamous sporadic CJDs that they are documenting to date, how do they know that none of these 6 variants will not transmit the agent (prion) via blood?...especially since the sporadic CJDs are the only ones documented to date to transmit via the surgical arena and now that the CWD is spreading more and more, who knows about the cattle?
I would always read this study and it would bring me back to reality as to how serious/dangerous this agent is in the surgical/medical arena. You might want to read this short abstract from the late, great Dr. Gibbs twice, and let it really sink in. And please remember while reading some of these transmission studies, that most all, if not ALL these agents transmit freely to primates. Humans, of course, are primates.
Regarding claims that:
'Well, it has never been documented to transmit to humans."
There are two critical factors to think about:
A. CJD/TSEs in the USA are NOT reportable in most states and there is NO CJD/TSE questionnaire for most victims and their families, and the one they are now issuing asks absolutely nothing about route and source of the (prion) agent, only how the disease was diagnosed. Furthermore, the elderly are only very rarely autopsied, ie looking for Alzheimer's or 'FAST Alzheimer's' OR prion disease-related factors and phenomena, such as heart failure caused by disease.
B. It is unethical and against the law to do transmission studies of TSEs to humans, they are 100% FATAL.
I suggest you read these case studies about medical arena CJD transmission very carefully:
1: J Neurol Neurosurg Psychiatry 1994 Jun;57(6):757-8
Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery.
Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.
Laboratory of Central Nervous System Studies, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD 20892.
Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them.
http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8006664&dopt=Abstract
Variant Creutzfeldt–Jakob Disease Diagnosed 7.5 Years after Occupational Exposure
July 2, 2020 N Engl J Med 2020; 383:83-85 DOI: 10.1056/NEJMc2000687
In May 2010, when the patient was 24 years of age, she worked in a prion research laboratory, where she handled frozen sections of brain of transgenic mice that overexpressed the human prion protein with methionine at codon 129. The mice had been infected with a sheep-adapted form of BSE. During this process, she stabbed her thumb through a double pair of latex gloves with the sharp ends of a curved forceps used to handle the samples. Bleeding was noted at the puncture site.
Appendix Case Study
See full text…
all iatrogenic cjd is, is sporadic cjd, before the iatrogenic event is discovered, traced back, proven, documented, put into the academic domain, and then finally the public domain, this very seldom happens, thus problem solved, it's all sporadic cjd. ...terry
Wednesday, July 28, 2021
France issues moratorium on prion research after fatal brain disease strikes two lab workers
Chronic Wasting Disease CWD ALERT CDC Jornal Ahead of Print 2025
CDC Journal ahead print into 2025 CWD not looking good!
Detection of Chronic Wasting Disease Prions in Raw, Processed, and Cooked Elk Meat, Texas, USA R. Benavente et al.
Prions in Muscles of Cervids with Chronic Wasting Disease, Norway T. T. Vuong et al.
Volume 31, Number 1—January 2025
Dispatch
Detection of Prions in Wild Pigs (Sus scrofa) from Areas with Reported Chronic Wasting Disease Cases, United States
Conclusions
In summary, results from this study showed that wild pigs are exposed to cervid prions, although the pigs seem to display some resistance to infection via natural exposure. Future studies should address the susceptibility of this invasive animal species to the multiple prion strains circulating in the environment. Nonetheless, identification of CWD prions in wild pig tissues indicated the potential for pigs to move prions across the landscape, which may, in turn, influence the epidemiology and geographic spread of CWD.
CDC, About Chronic Wasting Disease (CWD)
KEY POINTS
Chronic wasting disease affects deer, elk and similar animals in the United States and a few other countries.
The disease hasn't been shown to infect people.
However, it might be a risk to people if they have contact with or eat meat from animals infected with CWD.
all iatrogenic CJD TSE PRION is, is sporadic CJD TSE PRION, before the iatrogenic event is discovered, traced back, proven, documented, put into the academic domain, and then finally the public domain, this very seldom happens, thus problem solved, it's all sporadic. with the many different human and animal TSE prion disease evolving into many different strains, exposure there from, immediate actions are urgently needed to stop friendly fire, iatrogenic TSE Prion from spreading across the medical and surgical theaters, across the globe...
Terry S. Singeltary Sr.
Monday, February 26, 2024
iatrogenic Prion Mechanism Diseases, or iTSE Prion Diseases, what if?
Creutzfeldt Jakob Disease CJD, BSE, CWD, TSE, Prion, December 14, 2024 Annual Update
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$5c8bc620$7c58d182@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" >>----------------------------------------------------------------- >> >> >> >> regarding your article; >> >>
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 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
Wasted days and wasted nights…Freddy Fender
Terry S. Singeltary Sr.
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