I would suggest you try new stain packs on your automated stainer, just to rule that out. AFTER you have changed and bleached your water baths. Do you change them daily?Good luck, j-----Original Message-----From: histonet-bounces@lists.utsouthwestern.edu on behalf of Melissa JansSent: Mon 1/31/2005 8:40 PMTo: histonet@lists.utsouthwestern.eduSubject: [Histonet] yeast and bacteria on slides I need some help!!We have been experiencing some yeast and bacteria showing up on some of our special stains.  It started about 2 weeks ago and seems to be sporadic (one day...no problems, the next day, several stains are affected).  The yeast and bacteria (rods) are clumped together all over the slide, on the tissue sections, around the sections and on the slide in areas where there is no tissue.  The stains we have seen the contamination are the Gram, PAS/D, PAS and GMS.  All of these stains are automated except the Gram, so I do not think the special stainer is the problem.Here is what I have eliminated as problem areas:-Processor solutions and paraffin (we cut and stained a block from another institute and had contamination) -Waterbaths, slide drying boards, water containers (used to fill waterbathes), stainer containers, ice pans (all of the mentioned have been thoroughly bleached)-Tap water and DI water (all water supplies have been tested by sending a sample to micro...there was no bacteria or yeast detected)-Stay-on used as a slide adhesive (smeared some on a slide and stained it)-Bad batch of slides (we have had contamination on two different slide sources (vendors)) Does anybody have any ideas?  What am I missing?  Any suggestions would be much appreciated. Melissa JansUniversity of Iowa Hospitals and Clinics__________________________________________________Do You Yahoo!?Tired of spam?  Yahoo! Mail has the best spam protection around http://mail.yahoo.com _______________________________________________Histonet mailing listHistonet@lists.utsouthwestern.eduhttp://lists.utsouthwestern.edu/mailman/listinfo/histonetConfidentiality Notice ** The information contained in this message may be privileged and is confidential information intended for the use of the addressee listed above. If you are neither the intended recipient nor the employee or agent responsible for delivering this message to the intended recipient, you are hereby notified that any disclosure, copying, distribution or the taking of any action in reliance on the contents of this information 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. Saint Josephs Health System, Inc.