[Histonet] ?bacterial/fungal contamination on slides

[Monfils, Paul]

Fungi can grow in a number of different aqueous stain solutions. One time a tech brought me a slide she had stained with GMS for fungi, together with the positive control slide she had run. I could see fungi on the test slide but there was no sign of silver staining.  The control slide showed positively stained fungi as expected, but also the same unstained fungi seen on the test slide. It turned out a fungus was growing in the aqueous solution of Fast Green we used as a counterstain for the GMS.