Figure 2.

A, Photomicrograph of a glomerulus in a dog with glomerular amyloidosis and concurrent thymoma. There is segmental expansion of the glomerular tuft by extracellular eosinophilic matrix which compresses the capillary lumens (HE stain, Bar = 50 μm). B, Same glomerulus stained with Masson's Trichrome reveals the material is pale blue and waxy. There is mild diffuse interstitial fibrosis (Masson's Trichrome, Bar = 50 μm). C, Glomerulus stained with Congo red demonstrating prominent peach staining of the glomerular mesangium. This material demonstrated faint apple‐green birefringence when viewed with polarized light (Congo red method, Bar = 50 μm). D, Same glomerulus as A and B stained with Jones methenamine silver (JMS) reveals that the extracellular material is not argyrophilic (JMS method, Bar = 50 μm)