Milwaukee shoulder crystals are best visualized with which stain?

Milwaukee shoulder crystals are best visualized with which stain?

• A. Gram stain
• B. Ziehl-Neelsen stain
• C. Papanicolaou stain
• D. Alizarin red stain

Answer: (D)

Milwaukee shoulder crystals are basic calcium phosphate crystals, specifically hydroxyapatite, deposited in the joint. To visualize calcium-containing crystals, you use a stain that binds calcium. Alizarin red S binds calcium and stains these crystals a reddish color, making hydroxyapatite crystals visible under light microscopy. The other stains serve different purposes—Gram stain for bacteria, Ziehl-Neelsen for acid-fast organisms, and Papanicolaou for cytology—so they don’t highlight calcium-containing crystals.

Milwaukee shoulder crystals are basic calcium phosphate crystals, specifically hydroxyapatite, deposited in the joint. To visualize calcium-containing crystals, you use a stain that binds calcium. Alizarin red S binds calcium and stains these crystals a reddish color, making hydroxyapatite crystals visible under light microscopy. The other stains serve different purposes—Gram stain for bacteria, Ziehl-Neelsen for acid-fast organisms, and Papanicolaou for cytology—so they don’t highlight calcium-containing crystals.