Renal biopsy done for a patient with proteinuria is shown in this PLATE. What is the most probable diagnosis?
ANSWER: (B) Renal amyloidosisREF: Robbins 8th ed chapter 6See PLATE - Key PLATE - KeyRENAL AMYLOIDOSIS:See amyloid stains in APPENDIX-24 below "HISTOLOGY/PATHOLOGY/ MICROBIOLOGY STAINS"(A) Congo red staining of renal amyloidosis: Amyloid (an abnormal protein) accumulates as extra-cellular deposits, nodular or diffuse, as pink, amorphous material. Initially, the deposits appear in the glomeruli: within the mesangia] matrix and along the basement membranes of the capillary loops. The glomerular architecture is almost totally obliterated by the massive accumulation of amyloid (arrow heads). Continuous accumulation of the amyloid will compress and obliterate the capillary tuft. With progression, amyloid deposits appear alsoperitubular and within the arteriolar wall, narrowing them (Large arrow). Congo red is a special staining, elective for amyloid. Renal involvement gives rise to proteinuria that may be severe enough to cause the nephrotic syndrome. Progressive obliteration of glomeruli in advanced cases ultimately leads to renal failure and uremia. Renal failure is a common cause of death(B) Polarized light microscopy of renal amyloidosis showing Apple green birefringence (arrow)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
Renal tuberculosis
Renal amyloidosis
Renal cell carcinoma
Crescentic glomerulonephritis
Amyloidosis