1) We had not been informed that the sample was in the lab
2) The hospital technician did not appear to be aware of the high-risk
nature of the disease.
This incident has highlighted two areas of concern in our Unit. Firstly we have no mechanism in place that requires the hospital to inform us when high risk biohazards come through our lab. Secondly, our mechanisms for dealing with "high risk" samples and disposing of such material need to be re-evaluated and improved.
My questions are:
How do other labs that are have high risk samples going through them
monitor the risk of the samples coming into the lab?
How do other labs handle and dispose of high risk biohazards?
Allan Mitchell
Richard Easingwood
richard.easingwood@stonebow.otago.ac.nz
Dear Allan & Richard,
Working at a state health department gives us a leg up on such
things. There are procedures in place for proper notification, handling
& disposal. We know what samples are being brought in for examination,
and since it is usually a physician who brings in any potentially danger-
ous specimens, we are made aware of any potential hazards. Usually, the
specimen has already been fixed, stained and embedded, which eliminates
the hazard. There are containers all around our lab for the disposal of
biohazards, and the safety office is responsible for their proper dispo-
sal. Having the hospital technician give you a list of specimens and
their condition (tissue, blocks, sections, etc.) before bringing them in
would be an obvious step. I can think of rationalizations for not doing
this, but maybe you can insist. If you have a safety office, by all
means get them involved. Good luck.
William Tivol
tivol@wadsworth.org
Has anyone heard of the slow viruses that can survive gluteraldehyde fixation?
We may not be looking after our staff if we think that fixed material is safe.
In our lab, we know what every specimen is before it arrives. When we have finished with the hazardous stuff, we autoclave it. (Actually, we autoclave everything that isn't wrapping paper or rejected manuscripts).
We work with human and animal serum products, multiple types of tissue sample (sometimes brain), viruses and bacteria. Most of the small samples are dumped into chlorox prior to autoclaving, even after that have been fixed.
On a similar note, there was an MSA-sponsored speaker a couple of years ago who was encouraging EM labs to make money by offering virus identification sevices to medical centers. The preparation protocol included advice to accept unfixed (ie. infectious), unidentified material and prepare negative stained samples on the bench in the laboratory.
Any comments on that?
Paul Webster, Ph.D
paul.webster@yale.edu
The infectious agents that are able to survive fixation are the prions. These agents contain protein only...no nucleic acid. Among these are Creutzfeld-Jakob, scrapie, kuru, Gersten-Straussler-Schenker, BSE (mad cow disease) and apparently some forms of Alzheimers.
It is known that formaldehyde does not inactivate them, not surprising since formaldehyde is one of the least cross-linking of all fixatives, so far as proteins are concerned. My understanding is that glut. does inactivate them, but don't take my word for it.
We are a CLIA and State certified human clinical laboratory, licensed for negative-stain virus identification. This has always been part of our function as a veterinary EM lab, and for about 5 years we have offered it as a service to the community. We do make a considerable amount of money from it. We accept samples only from certain reference laboratories and practitioners and these are only stool samples, mostly (>95%) from infantile diarrheas. Our submission form has an entry for any unusual precautions that must be taken (ie HIV, hepatitis, etc). Our understanding with our clients is that we don't process such samples.
W. L. Steffens, Ph.D
STEFFENS.B@calc.vet.uga.edu
This information is at least 4 years old and may not be correct. About 4 years ago (maybe a little longer) there was a lengthy review article in either New England Journal of Medicine or JAMA regarding the slow human neurological disorders. At that time, there were at least 5 recognized diseases that were classified as "Alzheimer" or "Alzheimer-like". One of these was suspected to be of prion origin, although by now it may be classified as something else.
One thing to consider if you are involved in studies involving human (or any mammalian) brain tissue is that in years past, prion diseases were commonly misdiagnosed as Alzheimers, and as humans (even pathologists) are not perfect, this still may be the case.
Buddy Steffens
STEFFENS.B@calc.vet.uga.edu
AD and prion diseases share the presence of amyloid precursor proteins (beta-PP, APrP) but they are distinct diseases, both starting at the synapse (beta-PP and PrP are proteins of the neuromuscular junction and CNS synapse). In some of the prion diseases prion amyloid plaques are seen together with paired helical filaments (NFT) making them "Alzheimer-like" as Budy writes.
Sverker Enestrom M.D., Ph.D.
SveEn@pai.liu.se
Greetings, My understanding was that you got prion diseases through eating contaminated samples, hopefully uncommon in the world's em prep rooms. Is there an airborne transmission route?
Tobias Baskin
baskin@biosci.mbp.missouri.edu
Personally I find a Snickers more satisfying. I have been told oth by my Vet and our OB/GYN that it is possible to contract the organism through the dust kicked up while kitty uses his litterbox not to mention when we have to change it.
Scott Whittaker
e-mail sdw@biotech.ufl.edu
The review article that I described earlier notes some cases of prion disease in neurosurgeons who had performed procedures on known infected patients in years past. Not exactly iron-clad evidence of alternative transmissibility....but still.
W. L. Steffens, Ph.D
STEFFENS.B@calc.vet.uga.edu
For those of us following this thread, the following statement issued today by USDA-APHIS will be of interest.
>The British Ministry of Health and Agriculture have announced today that >they may have associated CJD to BSE - an announcement was made to the >House of Commons today.
I suppose in the future, we may be refusing to allow bovine tissues into our labs.
W.L. Steffen
STEFFENS.B@calc.vet.uga.edu
> Dear Richard, Try contacting James Ironside at the Department of Neuropathology, Western General Hospital, Crewe Road, Edinburgh, Scotland, EH4 2XU. He is in charge of one of the UK reference laboratories for J-C disease and has contributed to the formulation of policies to deal with infected or potentially infected J-C material.
I'm sorry, I don't have an E-mail address or telephone number for him.
Here at Tulane Medical School Hospital and Clinic we have Quality assurance and quality controls which are required in the USA for accreditation. If you wish more details let me know.
Richard,
Though I no longer work in the pathology EM lab, my experience may be of
help. In the US, hospital laboratories are required to practice "universal
precautions". U.P. assumes that EVERY specimen is a serious biohazard.
Therefore, gloves are used all the time when handling unfixed specimens,
goggles are worn, the hood is used if possible, a fluid resistant lab coat
is worn (buttoned up), absolutely no food/drink/cosmetics or personal items
are allowed in the lab area and hands are washed with religious fervor. Lab
coats may not be worn out of the lab area (certainly not to the cafeteria).
Its all rather onerous, but considering patient confidentiality issues, you
can never guarantee you will be notified "in advance" that a specimen is
AIDS/HIV+ or hepatitis+ or C-J disease+. I might add that the hospital paid
to have most of my immunizations checked or re-done in the 10 years I worked
there (polio, rubella, rubiolla, hepatitis).
We treat EVERYTHING of human origin as a high risk biohazard. All materials in contact with the samples we obtain are burned. We always wear gloves when handling human samples, and always work in a high-draw fume cabinet. Like you, we request that we be informed if the samples have a known risk, but do not depend in that information for our safety.
I used to work in the pathology department at a large medical center here in the 'States. I was on the research side of things, but helped out in the clinical lab. The deal here seems to be that the docs are not required to inform the labs of any potential hazards of a particular piece of tissue - everything is to be treated as if it were infetious. What actually happens is that most of the pathologists tell the techs when something is a big nasty...but not all of them do so. This is for EM,of course. Cryo (unfixed) material IS usually tagged - there are special cryostats set aside for HIV, etc. infected samples. I guess the reasoning for the "no need to inform" policy gets back to the assumption that everything is treated as infected...otherwise, samples that the pathologists don't KNOW are infected with soemthing and later turn out to be will have been handled in a safe manner all the way along. Scary places to work.
Are your techs required to go through a "blood-borne pathogens" training? This is required annually at the place I was - even for the research people who work with human tissues.
I hope your tech is OK. I'd suggest, again, that they assume everything is deadly if it comes from a human patient
I was the manager of EM lab for the section of Neuropathology At the Yale University School of Medicine. The investigators that I worked for primary research for more than 30 years is C-J. I agree that you should have been told the nature of the samples but the risk in this case was minimal. I went off the wall when a resident plopped bloody vials ( with HIV positive liver) on my desk, not in the hood. The agent was only classified as P2 when I was there now it's a P3. Osimum make the agent inert after 1 hour, we did some experiments to determine this.
In a recent CAP today (January 1996), there was an article by B.J. Crain, MD, PhD on safety tips for anatomic studies of possible CJD.
She talks about universal precaustions, cut resistant gloves, mask, eye shield d uring autopsy--although there is no evidence that the virus is transmitted by aerosols or non penetrating mucosal contamination.
Decontaminating should include autoclave. Incinerate disposables in bio- hazard bags. dDisinfect liquids on autopsy table with bleah or 2 N NaOH
Leave these disinfectants on the surface for 15-60 minutes.
decontaminating tissue--use formalin fixation followed by formic acid treatment of tissue blocks. Fix brain in formalin for at least 10 days prior to cutting. Agitate the tissue blocks in 50-100 ml of 95-100% formic acid for one hour, then return to formalin for2 days prior to embedding.
The article goes on to say that the tissue shoudl be handled with double gloves at all times. Treat solutions with eq ual volumes of fresh undiluted bleach for 60 minutes... Collect all paraffin and unused seciont on a sections on a disposable sheet and incinerate. Use disposable microtome blades. etc.
There is a reference by Brown, P. Guidelines for high risk autopsy cases: special precautions for CJD. IN Hutchins G. ed Autopsy Performance and Reporting. Northfield Il: Collefe College of American Pathologis, 1990:68-74.
Brown, P, Wolff, A, Gajdusek, DC. A simple and effective method for inactivating virus infectivity in formalin fixed tissue samples from patienst with CJD. Neurology. 1990, 40:887-890.
Since this disease has had a fair degree of expsoure on the TV recently can someone describe what it is and how it could be related to the BSE disease?
Please keep it in laymans terms if you can, I am a physicist not a physician!
Many thanks.
And sorry this isn't a Microscopy question.
John Mansfield
Email: jfmjfm@engin.umich.edu
There is an excellent review article on prions (the affecting agents of such diseases) in Scientific American by Prusiner. I believe that it was published in 1994 though I am not sure about this.
Wayne England
wengland@ccs.carleton.ca
The article "The Prion Diseases" by Stanley B. Prusiner appeared in Scientific American of January 1995 (vol. 272 no. 1), p.48.
Alfred Kracher
akracher@iastate.edu
Here's a simplified version of the mad cow disease story:
The connection between BSE and C-J Disease is that both are thought to be caused by prions, which are self-replicating, abnormally folded, mutated versions of a normal cellular protein. There are similar diseases in other species, the most notable being scrapie in sheep. The diseases have relatively long incubation periods (years) and result in a characteristic "spongiform" lesion in the brain. The diseases are easily diagnosed post-mortem by the presence of little holes in the brain, which can be detected with light microscopy. Prion particles themselves can be visualized with negative staining and TEM.
Great Britain has had a huge problem with BSE beginning in the late 1980's. The problem in beef was caused by feeding scrapie-infected sheep scraps to cattle, and there is good evidence that the disease jumped from sheep to cattle. The fear is that if it could make that jump, then maybe it could jump from cattle to humans. No one has thought to wonder, if that were the case, why it hasn't jumped from sheep to humans, since mutton is commonly eaten in Great Britain; but this story is not about logic - it's about sensationalism.
C-J Disease sporadically and spontaneously occurs in about 1 in a million humans. (There is another human prion disease called kuru that is transmitted by eating human brains - the solution to that health problem is pretty straightforward!) Until a few weeks ago, the British health department has been adamantly sticking to the story that there was no evidence for an increased incidence of C-J corresponding with the current epidemic of BSE in British cattle. However, they recently wavered and said they couldn't rule out a BSE connection to 10 cases of a variant form of C-J that appears to have a shorter than usual incubation period. The British press has had a heyday with that, and I noticed that even the Chicago Tribune had a headline in yesterday's paper stating that an Italian had died of mad cow disease. It's not likely that the disease would be transmitted by eating beef from infected cattle, particularly because prions reside in central nervous system tissues (brain and spinal cord), and humans don't normally eat those.
The problem in Britain right now is the proverbial tempest in a teapot. The sad part is that many farmers are losing their livelihoods because the British press was irresponsible in the way it reported the information from the health department.
Enough said, I guess, before I climb any higher on the soapbox!
Jane A. Fagerland, Ph.D.
FAGERLAND.JANE@igate.pprd.abbott.com
Thanks for all the comments concerning my remarks about prion diseases. I stand corrected on my assertion that humans don't usually eat central nervous system tissue from sheep and cattle. Several folks from the UK enlightened me - sheep and calf brains are considered a delicacy in some areas of the UK and are also used as fillers in hamburger and sausage. Also, soups are made from animals parts that may still have CNS tissues attached to them.
Someone also pointed out that it was initially thought that scrapie could not jump from sheep to cattle; thus, there's precedent for inter- animal transmission, regardless of what seems likely right now.
For anyone wanting more information on BSE, there is now a BSE group.
To subscribe, send an e-mail to
Jane A. Fagerland, Ph.D.
Subject: Re: BSE and C-J Disease
With reference to the BSE and CJD letters. While there is of course a
very faint chance that any of us can catch the any of the rarest of
diseases in the same way that we can be struck by lightning, the chances
of getting CJ from eating beef are marginally less that winning the big
prize on the UK National Lottery. I am quite content to eat muscle beef
and I buy a lottery ticket each week. I think you Americans have long had
the right idea in the you never eat meat that has come from the "engine
room". Leaving aside the bio-medical and econo-agricultural aspects of
BSE there is of course a delicious UK political and EURO political aspect
to this sorry story
Patrick Echlin
FAGERLAND.JANE@igate.pprd.abbott.com
pe13@cus.cam.ac.uk