Which stain is used to demonstrate iron deposits such as hemosiderin?

• A. Perl's Prussian Blue
• B. Hematoxylin & Eosin
• C. Luxol fast blue
• D. Papanicolaou

Answer: (A)

The stain used to demonstrate iron deposits such as hemosiderin is the Prussian blue reaction. This stain specifically targets ferric iron (Fe3+) in tissues. When ferric iron is present, it reacts with potassium ferrocyanide under acidic conditions to form an insoluble blue ferric ferrocyanide compound, which appears as blue granules or deposits. Hemosiderin, an iron-storage complex that shows up after hemorrhage or chronic blood breakdown, appears blue with this stain, making its presence easy to identify under the microscope.

Other stains don’t specifically reveal iron deposits: Hematoxylin and eosin is a general morphological stain and won’t highlight iron; Luxol fast blue targets lipids and myelin; Papanicolaou is a cytology stain used for exfoliated cells.