Another thought!
Necrotic tumour will often take up calcium giving a
positive Von Kossa's and Alizarin Red S reaction.
Possibly, dying or dead liver cells, as would be
expected in severe caseses of haemochromatosis, might
likewise appear to have iron present throughout the
cell including the nucleus. So, rather than being a
diffusion problem in the stain, it may be a diffusion
problem of the actual iron.

Though I have noted in the past, especially when the
Perl's reaction is accelerated via heat (eg microwave
oven) that there is a tendency for an increased
background staining. This, though, is rare with room
temperature incubations of 15 to 30 minutes.

My 2c worth.


--- Tony Henwood  wrote: >
Andrew,
> Try a different control.
> You probably have an iron control that is so full of
> iron, that it will set of a security alarm!! Try a
> liver with mild siderosis, or possibly spleen.
>  
> 
> 
> --- Andrew Kennedy 
> wrote: > Hi Histonetters,
> > 
> > A quality assurance survey that our lab
> participates
> > in, tested us out on
> > our Perl's Iron stain - the test sections were
> > marked as satisfactory but
> > our control section was deemed unsatisfactory due
> to
> > a "diffusion of
> > reaction product into the surrounding tissue,
> > including nuclei". Does anyone
> > have any ideas on how to fix this? Is it a problem
> > with the stain or the
> > tissue we use as a control?
> > 
> > Thanks in advance,
> > 
> > Andrew Kennedy
> > 
> > Senior Science Officer in charge - Histopathology.
> > Department of Anatomical Pathology
> > Concord Repatriation General Hospital
> > Hospital Road
> > Concord, NSW, Australia
> > 2139
> > Phone: +612 9767 6115
> > Fax: +612 9767 8427
> > 
> > "Noli illegitimi carborundum"
> > 
> >
>
----------------------------------------------------------------------------
> > ----------------------------------
> > This message is intended for the addressee(s)
> named
> > and may contain
> > confidential information. If you are not an
> intended
> > recipient, please
> > delete this email and notify the sender. Views
> > expressed in this message
> > are those of the individual sender and are not
> > necessarily the views of
> > Central Sydney Area Health Service.
> >
>
----------------------------------------------------------------------------
> > ----------------------------------
> > 
> >  
> 
> =====
> Tony Henwood JP BAppSc GradDipSysAnaly CT(ASC)
> Laboratory Manager
> Histopathology Department
> The Childrens Hospital at Westmead
> Locked Bag 4001
> WESTMEAD, 2145
> AUSTRALIA
> 
> http://my.yahoo.com.au - My Yahoo!
> - It's My Yahoo! Get your own!
>  

=====
Tony Henwood JP BAppSc GradDipSysAnaly CT(ASC)
Laboratory Manager
Histopathology Department
The Childrens Hospital at Westmead
Locked Bag 4001
WESTMEAD, 2145
AUSTRALIA

http://my.yahoo.com.au - My Yahoo!
- It's My Yahoo! Get your own!