<prompt> Which one of the following stains is specific for Amyloid?Periodic Acidschif PASAlzerian redCongo redVon -Kossa  <response>: Ans. is c i.e., Congo Red To differentiate amyloid from other hyaline deposits eg. Collagen andfibrin, a variety of histochemical techniques are used, of which the most widely used is Congo Red - Robbins 7the p. 259Staining for Amyloido Congo red : It is the most widely used specific stain for amyloid.o Iodine staining: It is used for unfixed specimen or histological section. Amyloid stains mahogany brown and if sulfuric acid is added, it turns violet.o Thioflavin T and S give secondary immunoflurescence with ultraviolet light. Thioflavin T is more useful for demonstrating juxtalomerular apparatus of the kidney,o Metachromatic stains like crystal violet and methyl violet give rose pink appearance,o Amyloid is PAS positive. 