: Tuesday, June 10, 2014 8:50 PM
To: Michael LaFriniere; histonet@lists.utsouthwestern.edu
Subject: [Histonet] RE: GMS better than PAS for Fungi
Hi Michael,
The PASM uses periodic acid, followed by the methenamine silver reaction. This
is usually for basement membranes, though some methods
I must disagree Tony, with my experience,using Periodic acid instead of chromic
acid in the GMS stain I have no problem demonstrating Pseudo fungi nor strong
results demonstrating Pneumocystis, think you may be confusing stains, this is
not a (PSAM)that I am aware of.
Michael R. LaFriniere,
Hi Michael,
The PASM uses periodic acid, followed by the methenamine silver reaction. This
is usually for basement membranes, though some methods, including mine, uses a
thiosemicarbazide step before the silver.
GMS uses Chromic acid followed by the methenamine silver reaction.
The idea of a
Freida Carson wrote what was probably the definitive study of the subject
about 15 years ago.
What stain you need depends on what fungus you're trying to stain. PAS does
fine for Candida. The most critical test of a fungal stain is its ability
to stain old (obsolete) Histoplasma.
Here's the
