Hello Histonetters,

First I would like to thank everyone who responded to my question regarding
the Jones staining technique.  I figured out that we had the wrong kind of
methenamine in our lab.  It was bound to a mandalate salt, which I believe
changed the pH making it not stain properly.

I would like to see a discussion on the topic of Chromic Acid vs. Periodic
Acid oxidation in
regards to the GMS for fungus.  Specifically, what types of fungus do not
stain if you use
Periodic Acid??  A long time ago someone said ????(can't remember what)
would not stain with Periodic Acid, so I tried both procedures and it
stained just fine in both.  I believe there was less background using
Periodic Acid, and our pathologists thought both were fine.  Also, could
there be a difference in using Ammoniacal silver vs. Methenamine silver??  I
believe this would be an interesting topic, as it has had much debate from
older vs. younger techs.  I had found an article a long time ago that stated
Periodic Acid-Ammoniacal Silver was preferred for pneumocystis on bronchial
bx specimens, having less background staining than chromic. I am not sure
this is true, since periodic acid also oxidizes mucin into reacting aldehyde
groups.

Thanks in advance,
Rhonda Allen

-----Original Message-----
From: R Clarke [mailto:rr_clarke@bc.sympatico.ca]
Sent: Thursday, February 25, 1999 6:58 PM
To: HistoNet Server
Subject: GROCOTT


Hi,

Does anyone have a method for Grocott without using Chromic Acid?
Thanks!

Rose Clarke
Burnaby Hospital