DIAGNOSTIC METHODS: Permanent Stains

What recent changes have influenced the overall quality of the permanent stained smear?

The use of mercury substitutes in PVA generally leads to diminished overall morphology quality of the intestinal protozoa. The use of alcohol other than 100% ethanol (95% - 5% mixture) for several of the dehydration steps will not provide as good dehydration. The use of xylene substitutes will usually not provide as good dehydration, but they are recommended for personnel safety. Isopropyl alcohol can be used for any alcohol in the staining procedure that is <100%. Absolute ethanol is recommended for the steps requiring 100% alcohol.

These comments are relevant for both the Trichrome and Iron Hematoxylin staining methods.