[Histonet] Re: von Kóssa method for calcium

[Bob Richmond]

Why is the von Kóssa method for calcified tissue still in use? It's
not very specific and requires handling silver. Why not alizarin red,
a simple dye that is more specific.

I've seen alizarin red S (C.I. 58005) used to demonstrate
microcalcifications in breast biopsy specimens. Obviously one can see
the more common calcium phosphate calcifications in the H & E, but the
less common calcium oxalate deposits (which are also visible to the
radiologist) are nearly invisible. I actually prefer polarization to
see calcium oxalate, but many pathologists don't have access to
polarizers.

Bob Richmond
Samurai Pathologist
Knoxville TN