Special Stains for Skin: Melanin and Amyloid

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Special Stains for Skin: Melanin and Amyloid

Special stain for melanin
Fontana-Masson is a silver stain that demonstrates melanin and is used to evaluate vitiligo and post-inflammatory hyperpigmentation.
  • Fontana-Masson stain for melanin: Demonstrates melanin pigment by staining it black.
Special stain for amyloid
Congo red is a stain for the detection of protein deposits caused by a disease process called amyloidosis, which can affect the skin, tongue, heart, and muscles. The stain is often visualized using a polarized microscope in which the amyloid deposits are exhibited by green birefringence.
  • Congo red stain for amyloid: Demonstrates amyloid deposits by staining it reddish pink, which can be visualized more clearly as an apple-green color with a polarized microscope.

Melanin pigment (black) in skin section
Polarized amyloid deposits