This is what I found at the CDC website: "Table 9. Tissue Preparation for Human CJD and Related Diseases 1. Histology technicians wear gloves, apron, laboratory coat, and face protection. 2. Adequate fixation of small tissue samples (e.g., biopsies) from a patient with suspected prion disease can be followed by post-fixation in 96% absolute formic acid for 30 minutes, followed by 45 hours in fresh 10% formalin. 3. Liquid waste is collected in a 4L waste bottle initially containing 600 ml 6N NaOH. 4. Gloves, embedding molds, and all handling materials are disposed s regulated medical waste. 5. Tissue cassettes are processed manually to prevent contamination of tissue processors. 6. Tissues are embedded in a disposable embedding mold. If used, forceps are decontaminated as in Table 10. 7. In preparing sections, gloves are worn, section waste is collected and disposed in a regulated medical waste receptacle. The knife stage is wiped with 2N NaOH, and the knife used is discarded immediately in a “regulated medical waste sharps” receptacle. Slides are labeled with “CJD Precautions.” The sectioned block is sealed with paraffin. 8. Routine staining: a. slides are processed by hand; b. reagents are prepared in 100 ml disposable specimen cups; c. after placing the cover slip on, slides are decontaminated by soaking them for 1 hour in 2N NaOH; d. slides are labeled as “Infectious-CJD.” 9. Other suggestions: a. disposable specimen cups or slide mailers may be used for reagents; b. slides for immunocytochemistry may be processed in disposable Petri dishes; c. equipment is decontaminated as described above or disposed as regulated medical waste. Handling and processing of tissues from patients with suspected prion disease The special characteristics of work with prions require particular attention to the facilities, equipment, policies, and procedures involved.10 The related considerations outlined in Table 9 should be incorporated into the laboratory’s risk management for this work. 288 Biosafety in Microbiological and Biomedical Laboratories Table 10. Prion Inactivation Methods for Reusable Instruments and Surfaces 1. Immerse in 1 N NaOH, heat in a gravity displacement autoclave at 121ºC for 30 minutes. Clean and sterilize by conventional means. 2. Immerse in 1 N NaOH or sodium hypochlorite (20,000 ppm) for 1 hours. Transfer into water and autoclave (gravity displacement) at 121ºC for 1 hour. Clean and sterilize by conventional means. 3. Immerse in 1N NaOH or sodium hypochlorite (20,000) for 1 hour. Rinse instruments with water, transfer to open pan and autoclave at 121ºC (gravity displacement) or 134ºC (porous load) for 1 hour. Clean and sterilize by conventional means. 4. Surfaces or heat-sensitive instruments can be treated with 2N NaOH or sodium hypochlorite (20,000 ppm) for 1 hour. Ensure surfaces remain wet for entire period, then rinse well with water. Before chemical treatment, it is strongly recommended that gross contamination of surfaces be reduced because the presence of excess organic material will reduce the strength of either NaOH or sodium hypochlorite solutions. 5. Environ LpH (EPA Reg. No. 1043-118) may be used on washable, hard, non-porous surfaces (such as floors, tables, equipment, and counters), items (such as non-disposable instruments, sharps, and sharp containers), and/or laboratory waste solutions (such as formalin or other liquids). This product is currently being used under FIFRA Section 18 exemptions in a number of states. Users should consult with the state environmental protection office prior to use. (Adapted from www.cdc.gov 11,12) Working Solutions 1 N NaOH equals 40 grams of NaOH per liter of water. Solution should be prepared daily. A stock solution of 10 N NaOH can be prepared and fresh 1:10 dilutions (1 part 10 N NaOH plus 9 parts water) used daily. 20,000 ppm sodium hypochlorite equals a 2% solution. Most commercial household bleach contains 5.25% sodium hypochlorite, therefore, make a 1:2.5 dilution (1 part 5.25% bleach plus 1.5 parts water) to produce a 20,000 ppm solution. This ratio can also be stated as two parts 5.25% bleach to three parts water. Working solutions should be prepared daily. CAUTION: Above solutions are corrosive and require suitable personal protective equipment and proper secondary containment. These strong corrosive solutions require careful disposal in accordance with local regulations. Precautions in using NaOH or sodium hypochlorite solutions in autoclaves: NaOH spills or gas may damage the autoclave if proper containers are not used. The use of containers with a rim and lid designed for condensation to collect and drip back into the pan is recommended. Persons who use this procedure should be cautious in handling hot NaOH solution (post-autoclave) and in avoiding potential exposure to gaseous NaOH; exercise caution during all sterilization steps; and allow the autoclave, instruments, and solutions to cool down before removal. Immersion in sodium hypochlorite bleach can cause severe damage to some instruments."
Hazel Horn Hazel Horn, HT/HTL (ASCP) Supervisor of Autopsy/Histology/Transcription Arkansas Children's Hospital 1 Children's Way Slot 820 Little Rock, AR 72202 phone 501.364.4240 fax 501.364.3155 visit us on the web at: www.archildrens.org -----Original Message----- From: histonet-boun...@lists.utsouthwestern.edu [mailto:histonet-boun...@lists.utsouthwestern.edu] On Behalf Of Emily Sours Sent: Friday, February 25, 2011 8:47 AM To: histonet@lists.utsouthwestern.edu Subject: Re: [Histonet] cdj Now I'm curious!! Please let us know what this mysterious processing is!! Emily It has become almost a cliche to remark that nobody boasts of ignorance of literature, but it is socially acceptable to boast ignorance of science and proudly claim incompetence in mathematics. -Richard Dawkins On Thu, Feb 24, 2011 at 6:46 PM, Pamela Marcum <mucra...@comcast.net> wrote: > > > The CDC website can tell you exactly what to do with a CJD case and it will > surprise you. > > > > Pam Marcum > > UAMS > > > > > > ----- Original Message ----- > From: "Kimberly K Marshall" <kkmarsh...@anthc.org> > To: histonet@lists.utsouthwestern.edu > Sent: Thursday, February 24, 2011 4:06:53 PM > Subject: [Histonet] cdj > > Hello everyone > > We recently recieved a case possible positive for CJD. In researching > this we have found that they now say Formalin is BAD. As long as I have > been a Histo tech it seems the rules were Formalin then Formic acid. > But seems there are some studies saying this is no longer enough. Is > there anyone out there that has changed and if so What are you doing > now??? > > > Thanks in advance > _______________________________________________ > Histonet mailing list > Histonet@lists.utsouthwestern.edu > http://lists.utsouthwestern.edu/mailman/listinfo/histonet > > > > > > > ----- Original Message ----- > From: "Kimberly K Marshall" <kkmarsh...@anthc.org> > To: histonet@lists.utsouthwestern.edu > Sent: Thursday, February 24, 2011 4:06:53 PM > Subject: [Histonet] cdj > > Hello everyone > > We recently recieved a case possible positive for CJD. In researching > this we have found that they now say Formalin is BAD. As long as I have > been a Histo tech it seems the rules were Formalin then Formic acid. > But seems there are some studies saying this is no longer enough. Is > there anyone out there that has changed and if so What are you doing > now??? > > > Thanks in advance > _______________________________________________ > 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 mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet ****************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************************** The information contained in this message may be privileged and confidential and protected from disclosure. If the reader of this message is not the intended recipient, or an employee or agent responsible for delivering this message to the intended recipient, you are hereby notified that any dissemination, distribution or copying of this communication is strictly prohibited. If you have received this communication in error, please notify us immediately by replying to the message and deleting it from your computer. Thank you.
_______________________________________________ Histonet mailing list Histonet@lists.utsouthwestern.edu http://lists.utsouthwestern.edu/mailman/listinfo/histonet
