Fig. 1.

Top left: diffuse tubulointerstitial inflammation, with some areas of the infiltrate showing morphological atypia in the form of hyperchromasia (right half of field) (H&E stain, ×100 magnification; scale bar, 50 μm). Top right: granular staining of proximal tubular basement membranes, Bowman's capsule, and segmental glomerular capillary walls (IgG IF stain, ×200 magnification; scale bar, 50 μm). Bottom left: small electron-dense immune complexes seen along proximal tubular basement membrane (transmission EM, approx. ×4,800 magnification; scale bar, 2 μm). Bottom right: small electron-dense immune complexes seen in subepithelial locations (membranous-type) and along Bowman's capsule (transmission EM, approx. ×2,900 magnification; scale bar, 4 μm). IF, immunofluorescence; EM, electron microscopy.