Special Stains and Histochemistry Flashcards
6 cards from real ASCP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Special Stains and Histochemistry flashcards as text
The Warthin-Starry stain is used to identify which organisms in tissue?
Answer: Spirochetes and Helicobacter pylori
Warthin-Starry is a silver-based stain that demonstrates spirochetes (e.g., Treponema) and Helicobacter pylori as black organisms on a yellow background.
Which histochemical stain is used to demonstrate calcium deposits in tissue?
Answer: Von Kossa stain
Von Kossa stain reacts phosphates and carbonates associated with calcium deposits, turning them black-brown.
What does Oil Red O stain identify in tissue sections?
Answer: Neutral lipids and triglycerides
Oil Red O is a lysochrome dye that stains neutral fats and lipids bright red; it requires frozen sections as lipids are removed during paraffin processing.
In the Prussian blue stain, what positive control tissue is typically used?
Answer: Liver with hemosiderosis or spleen with iron deposits
Liver or spleen from a case with known hemosiderosis or iron overload serves as a reliable positive control for Perl's Prussian blue stain.
Which stain differentiates hyaline cartilage from fibrocartilage in musculoskeletal histology?
Answer: Safranin O/Fast Green
Safranin O stains proteoglycans (found in hyaline cartilage matrix) red-orange, while fibrocartilage with less proteoglycan appears green with Fast Green counterstain.
What is the role of the mordant in a silver impregnation stain like GMS?
Answer: To sensitize tissue so it adsorbs silver ions
The mordanting step (chromic acid oxidation in GMS) sensitizes the fungal cell wall by creating aldehyde groups that subsequently reduce silver.