Fig. 1.

Photomicrographs of the renal biopsy tissue. a, b Light microscopy shows segmental endocapillary hypercellularity and increased mesangial matrix and mesangial hypercellularity with double contour of the GBM. a PAS staining. b PAM staining. Original magnification, × 400. c The direct immunofluorescence study showed bright linear IgG staining on all GBMs. d On the GBM, IgG1 was the dominant IgG. e Immunofluorescence for C3c showed granular staining on the mesangial area. f Immunofluorescence for C4d showed linear staining on the GBMs and mesangial area. Electron microscopic findings. g Immunofluorescence for κ showed linear staining along the GBMs. h Immunofluorescence for λ also showed linear positivity along the GBMs. i Subepithelial, intra-basemembrane, subendothelial, and paramesangial electron dense deposits were presented. GBM, glomerular basement membrane. j Higher-magnification electron micrograph showing electron-dense immune complex deposits (arrow) within a partially exudative-appearing lesion and the subendothelial glomerular basement membrane. k Higher-magnification electron micrograph showing that linear IgG deposition along the glomerular basement membrane did not correspond to the electron-dense immune complex deposits