We have never considered that to be an issue.   I don't really see how that
could happen when using tissue as a control.  Perhaps with a wet prep (we
get these from micro for gram stain controls) but it seems highly unlikely
that an organism embedded in a piece of tissue could dislodge and migrate.
Even if it did, wouldn't it show up on the surface of the other tissue
rather than as a part of it?  What do others think?

Tom Mc Nemar
Pathology Supervisor
Licking Memorial Hospital
Newark, Ohio

> -----Original Message-----
> From:	Tapper, Sheila [SMTP:STapper@smdc.org]
> Sent:	Monday, March 20, 2000 4:05 PM
> To:	'Tom T. McNemar'; Colbert, Laurie; 'histonet@pathology.swmed.edu'
> Subject:	RE: Automation of Special Stains - QC
> 
> Have you ever had trouble with microorganisms traveling from your positive
> control to the patient tissue?  My pathologist refuses to allow
> microorganism controls to be placed on the same slide, for fear that
> something may contaminate the patient tissue.  
> 
> Sheila
> 
> 	-----Original Message-----
> 	From:	Tom T. McNemar [SMTP:TMcNemar@lmhealth.org]
> 	Sent:	Monday, March 20, 2000 10:26 AM
> 	To:	Colbert, Laurie; 'histonet@pathology.swmed.edu'
> 	Subject:	RE: Automation of Special Stains - QC
> 
> 	With regard to the question of positive/negative controls.....  In
> our lab
> 	we mount the positive control on the same slide as the patient.
> This way
> 	you always know that the control and patient were stained exactly
> the same.
> 	Granted, we go through a huge number of control blocks but so far
> they have
> 	been pretty easy to come by.  We buy special slides that have a red
> box for
> 	the control tissue.  It has worked well for us.
> 	Tom Mc Nemar
> 	Pathology Supervisor
> 	Licking Memorial Hospital
> 	Newark, Ohio
> 
> 
> 	> -----Original Message-----
> 	> From:	Colbert, Laurie [SMTP:LColbert@phsca.org]
> 	> Sent:	Sunday, March 19, 2000 2:37 PM
> 	> To:	'histonet@pathology.swmed.edu'
> 	> Subject:	RE: Automation of Special Stains
> 	> 
> 	> In the past we used the Leica Autostainer to do some special
> stains.  This
> 	> worked well, but large amounts of reagent were needed to fill the
> slide
> 	> buckets on the stainer and the number of stains that could be
> performed at
> 	> one time was limited.
> 	> 
> 	> We now have two Cytologix stainers in our lab.  One was purchased
> and one
> 	> is
> 	> on loan until Cytologix can improve on the turn-around time.  The
> stains
> 	> are
> 	> really nice on this stainer, but there are a  few problems with
> 	> consistency.
> 	> The stainer can accommodate 48 slides at one time, but, as I
> mentioned
> 	> earlier, the turn-around time is not good when you have multiple
> stains or
> 	> multiple slides (more that 3 or 4) slides of one stain.  What is
> really
> 	> nice
> 	> is that we can run stains overnight and they are ready to hand out
> first
> 	> thing in the morning.  So this aspect has improved our turn-around
> time.
> 	> 
> 	> Cytologix is aware of the problems with their stainer, and they
> are very
> 	> receptive to any issue or problem we have had.  I think this is
> going to
> 	> be
> 	> a really great stainer down the line when some of the bugs have
> been
> 	> worked
> 	> out.  For now, we will continue work around the problems, and the
> stainer
> 	> really has saved us several times when we were short on people.
> And I
> 	> have
> 	> to emphasize that their customer service has been good.
> 	> 
> 	> I may be opening a can of worms here, but I have a question in
> regards to
> 	> automation of stains.  I feel there is no real quality control on
> the
> 	> stainers that stain one slide at a time (vs. batch staining as on
> the
> 	> Leica
> 	> Autostainer).  Sure, your control may be positive, but how do you
> know the
> 	> patient slide was stained properly when it is stained independent
> of the
> 	> control slide?  We have had our control slide come out negative,
> but our
> 	> patient was positive, so who's to say that this couldn't  happen
> the other
> 	> way around???
> 	> 
> 	> Laurie Colbert
> 	> Saint Joseph Medical Center
> 	> Burbank, CA