Amyloid is stained by?

ANSWER: (B) Congo redREF: Robbins 7th edition page 263Repeat from Primary DNB CET June 2009, December 2008See APPENDIX-24 below for "HIS TO LOGY/PATHOLOGY/ MICROBIOLOGY STAINS"The histological diagnosis of amyloid is based almost entirely on its staining characteristics.* The most commonly used staining technique employs the dye Congo red, which under ordinary light imparts pink or red colour to amyloid deposits.* Under polaried light, the Congo red stained amyloid shows a green birefringence.* Confirmation is done by electron microscopy (beta pleated on electron microscope) APPENDIX - 24Histology/Pathology/Microbiology StainsT issue/substanoeStainCommentAmyloidGross stainingLugol's iodine Light microscopyH & E, Congo redPolarised lightCongo redMetachromatic stainMethyl violet, crystal violetFluorescent stainThioflavin TNon specific stainPAS, Toludine blue. Aldan blueCaldum/calcificationVon kossa Alizarin Red SFor small quantitiesCalcein Tetracycline labellingBest for bone mineralizationConnective tissueVan Gieson stain (Picric Add + Acid Fuchsin)Simplest method of differential staining of Collagen and other Connective TissueTrichome stain (Gomori trichrome stain, Lillie's trichome & Masson trichome)Red = keratin/muscleBlue/green = bone /'collagenPink = cytoplasmCarcohydrate (Glycogen, cellulose etc)Periodic acid-Schiff stainNon specific for glycogenDiastaseSpecific for glycogenBest's carmine LipidSudan stains{Sudan III, IV, Sudan Back-B, Oil Red 0)Oil Red O largely replaced Sudan III and Sudan IVOil Red O is also used in a technique for staining latent fingerprintsOsmium tetra oxideAs a lipid stain, it is useful in scanning electron microscopy (SEM)LipofuscinSudan Black B MucinMuscarmineMost specific but less usefulPASMost sensitive, For neutral mucopolysaccharidesAlcian blue Bismark brownCan be used with live cellsColloidal iron Micro organismsFungiH & EBluePASRedGomori methamine silverMost sensitiveMycobacteriumZ N stain/methodCarbol fuchsinAuramine Rhodamine stainMost sensitive, mixture of Auramine O and Rhodamine B, used in fluorescence microscopySpirochetesWarthin starry silver stain H PyloriWarthin starry silver stainGiemsa stainH&E Pneumocystis/ Cryptococcus/ cocci diomycetesGomori methamine silver