RE: [Histonet] RE: Prion Contamination
All, The formic acid is a post-fixation step. http://www.cdc.gov/od/ohs/biosfty/bmbl4/bmbl4s7d.htm#Table%205.%20Tissue %20preparation Jeanine Bartlett, BS, HT(ASCP)QIHC Centers for Disease Control and Prevention Infectious Diseases Pathology Branch 1600 Clifton Road, MS/G-32 18/SB-114 Atlanta, GA 30333 (404) 639-3590 jeanine.bartl...@cdc.hhs.gov -Original Message- From: histonet-boun...@lists.utsouthwestern.edu [mailto:histonet-boun...@lists.utsouthwestern.edu] On Behalf Of joelle weaver Sent: Thursday, January 22, 2009 6:46 PM To: sal...@exchange.hsc.mb.ca; Histonet Subject: RE: [Histonet] RE: Prion Contamination I just researched this recently for procedure writing. I referenced an article from the CDC that made mention of specific handling guidelines for histology, and also specifically the formic acid treatment step. I do not have the article in front of me, but by my recollection I believe that it stated that the formic acid was a post-fixation step. I found this article relatively easily by using the search field for CJD from the CDC website. You can check my recollection here: http://www.cdc.gov/od/ohs/biosfty/bmbl5/sections/SectionVIIIH-PrionDisea ses.pdf Thanks Joelle Weaver HTL(ASCP) Date: Thu, 22 Jan 2009 13:21:25 -0600 From: sal...@exchange.hsc.mb.ca To: tbr...@holyredeemer.com Subject: [Histonet] RE: Prion Contamination CC: histonet@lists.utsouthwestern.edu Hi, I was reading your email of Jan. 15/09 on the subject of Prion Contamination. In it you had made the following statement, which I was curious as to where this information had come from. the procedure to inactivate using formic acid is followed before fixation and processing. If the tissue is fixed (formalin or other common fixatives) then you would be actually fixing the prion's ability to NOT be inactivated. I had read again the WHO Guidelines on CJD that you had a link to could find no mention of the fact that the formic acid step for de-activating the prions had to be done before any fixation. The WHO instructions: P. 18 8.2.2 Histopathological examination: states formic acid treatment consists of placing small pieces of fixed tissue, no more than 4 to 5 mm thick, in 50 to 100 ml of 95% formic acid for an hour. I have been dealing with CJD brains for many years always following the CDC, WHO Health Canada guidelines but have never read any studies that had indicated that the fixing in formalin made the treatment in formic acid ineffective. If you have any further information I would really appreciate seeing it. Thank you S. Allen sal...@hsc.mb.ca _ Windows Live(tm): E-mail. Chat. Share. Get more ways to connect. http://windowslive.com/explore?ocid=TXT_TAGLM_WL_t2_allup_explore_012009 ___ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet ___ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
[Histonet] RE: Prion Contamination-Post Fixation
Ooops, my bad!..you are both right! Another reason that prion contaminated tissues should be left to the experts. And for the rest of us, just read the links for yourself, and try to be safe! Thanks, Terri Terri L. Braud, HT(ASCP) My recollection I believe that it stated that the formic acid was a post-fixation step. Joelle Weaver HTL(ASCP) All, The formic acid is a post-fixation step. Jeanine Bartlett, BS, HT(ASCP)QIHC Centers for Disease Control and Prevention Infectious Diseases Pathology Branch 1600 Clifton Road, MS/G-32 18/SB-114 Atlanta, GA 30333 (404) 639-3590 jeanine.bartl...@cdc.hhs.gov - CONFIDENTIALITY NOTICE: This E-Mail is intended only for the use of the individual or entity to which it was sent. It may contain information that is privileged and/or confidential, and the use or disclosure of such information may also be restricted under applicable federal and state law. If you received this communication in error, please do not distribute any part of it or retain any copies, and delete the original E-Mail. Please notify the sender of any error by E-Mail. Thank you for your cooperation. ___ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
[Histonet] RE: Prion Contamination
Hi, I was reading your email of Jan. 15/09 on the subject of Prion Contamination. In it you had made the following statement, which I was curious as to where this information had come from. the procedure to inactivate using formic acid is followed before fixation and processing. If the tissue is fixed (formalin or other common fixatives) then you would be actually fixing the prion's ability to NOT be inactivated. I had read again the WHO Guidelines on CJD that you had a link to could find no mention of the fact that the formic acid step for de-activating the prions had to be done before any fixation. The WHO instructions: P. 18 8.2.2 Histopathological examination: states formic acid treatment consists of placing small pieces of fixed tissue, no more than 4 to 5 mm thick, in 50 to 100 ml of 95% formic acid for an hour. I have been dealing with CJD brains for many years always following the CDC, WHO Health Canada guidelines but have never read any studies that had indicated that the fixing in formalin made the treatment in formic acid ineffective. If you have any further information I would really appreciate seeing it. Thank you S. Allen sal...@hsc.mb.ca This email and/or any documents in this transmission is intended for the addressee(s) only and may contain legally privileged or confidential information. Any unauthorized use, disclosure, distribution, copying or dissemination is strictly prohibited. If you receive this transmission in error, please notify the sender immediately and return the original. Ce courriel et tout document dans cette transmission est destiné à la personne ou aux personnes à qui il est adressé. Il peut contenir des informations privilégiées ou confidentielles. Toute utilisation, divulgation, distribution, copie, ou diffusion non autorisée est strictement défendue. Si vous n'êtes pas le destinataire de ce message, veuillez en informer l'expéditeur immédiatement et lui remettre l'original. ___ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
RE: [Histonet] RE: Prion Contamination
I just researched this recently for procedure writing. I referenced an article from the CDC that made mention of specific handling guidelines for histology, and also specifically the formic acid treatment step. I do not have the article in front of me, but by my recollection I believe that it stated that the formic acid was a post-fixation step. I found this article relatively easily by using the search field for CJD from the CDC website. You can check my recollection here: http://www.cdc.gov/od/ohs/biosfty/bmbl5/sections/SectionVIIIH-PrionDiseases.pdf Thanks Joelle Weaver HTL(ASCP) Date: Thu, 22 Jan 2009 13:21:25 -0600 From: sal...@exchange.hsc.mb.ca To: tbr...@holyredeemer.com Subject: [Histonet] RE: Prion Contamination CC: histonet@lists.utsouthwestern.edu Hi, I was reading your email of Jan. 15/09 on the subject of Prion Contamination. In it you had made the following statement, which I was curious as to where this information had come from. the procedure to inactivate using formic acid is followed before fixation and processing. If the tissue is fixed (formalin or other common fixatives) then you would be actually fixing the prion's ability to NOT be inactivated. I had read again the WHO Guidelines on CJD that you had a link to could find no mention of the fact that the formic acid step for de-activating the prions had to be done before any fixation. The WHO instructions: P. 18 8.2.2 Histopathological examination: states formic acid treatment consists of placing small pieces of fixed tissue, no more than 4 to 5 mm thick, in 50 to 100 ml of 95% formic acid for an hour. I have been dealing with CJD brains for many years always following the CDC, WHO Health Canada guidelines but have never read any studies that had indicated that the fixing in formalin made the treatment in formic acid ineffective. If you have any further information I would really appreciate seeing it. Thank you S. Allen sal...@hsc.mb.ca _ Windows Live™: E-mail. Chat. Share. Get more ways to connect. http://windowslive.com/explore?ocid=TXT_TAGLM_WL_t2_allup_explore_012009___ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
[Histonet] RE: Prion Contamination
Not only will processing NOT render it safe, but your cut, stained, and mounted slides will still be infectious UNLESS the procedure to inactivate using formic acid is followed before fixation and processing. If the tissue is fixed (formalin or other common fixatives) then you would be actually fixing the prion's ability to NOT be inactivated. Prions are nasty little beasties, and best left to dedicated labs that do nothing else. Please refer to the link below for the WHO pdf document which will give you procedures for handling prion infected patient's and tissues. http://www.who.int/csr/resources/publications/bse/whocdscsraph2003.pdf Section 8.2.2 directly addresses the Histopathology techniques to be used when handling these tissues. So much about these self replicating proteins is unknown, and more forms are added to the list all the time. Currently, the CDC recognizes 5 human forms, including, Creutzfeldt-Jakob Disease (CJD) Variant Creutzfeldt-Jakob Disease (vCJD) Gerstmann-Straussler-Scheinker Syndrome Fatal Familial Insomnia Kuru There are also 6 Animal Prion Diseases: Bovine Spongiform Encephalopathy (BSE) Chronic Wasting Disease (CWD) Scrapie Transmissible mink encephalopathy Feline spongiform encephalopathy Ungulate spongiform encephalopathy See the CDC link below for more information http://www.cdc.gov/ncidod/dvrd/prions/ and above all, Please, Please, Please be very careful. Terri L. Braud, HT(ASCP) Anatomic Pathology Supervisor Laboratory Holy Redeemer Hospital and Medical Center 1648 Huntingdon Pike Meadowbrook, PA 19046 (215) 938-3676 phone (215) 938-3689 fax --- On Thu, 1/15/09, Joe Hardin har...@oncology.wisc.edu wrote: From: Joe Hardin har...@oncology.wisc.edu Subject: [Histonet] prion contaminated tissue processing To: histonet@lists.utsouthwestern.edu Date: Thursday, January 15, 2009, 10:29 AM Hi All, Does anyone know if tissue processing for paraffin embedding will render prion infected tissue safe for sectioning? - CONFIDENTIALITY NOTICE: This E-Mail is intended only for the use of the individual or entity to which it was sent. It may contain information that is privileged and/or confidential, and the use or disclosure of such information may also be restricted under applicable federal and state law. If you received this communication in error, please do not distribute any part of it or retain any copies, and delete the original E-Mail. Please notify the sender of any error by E-Mail. Thank you for your cooperation. ___ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
