Fig. 1.

Pathological studies on renal biopsy sample. a Light microscopy, ×40, b light microscopy shows glomerulus with thick and irregular capillary loops, ×400, c frequent GBM spikes on silver stain, ×400, d patchy dense interstitial lymphoplasmacytic inflammatory infiltration, ×400, e an IgG4 immunoperoxidase stain shows patchy positive staining of the interstitium as well as locally more than 10 IgG4 positive plasma cells per high-power field, ×400, f immunofluorescence shows glomerular IgG, ×200, g immunofluorescence shows tubular basement membrane staining by IgG, ×200, h electron microscopy shows glomerular basement membrane with frequent subepithelial immune complex-type electron dense deposits, ×5000