Figure 1.

Renal biopsy findings in membranous-like glomerulopathy with masked IgG κ deposits. (a) Segmental “spikes” and “holes” are present along the glomerular basement membranes by Jones methenamine silver stain (original magnification ×400). (b) Electron microscopy reveals numerous large subepithelial deposits present along the glomerular basement membrane (unstained, original magnification ×12,000). (c) Glomeruli stain negative for IgG by routine immunofluorescence on fresh tissue. (d) Glomeruli from the same case stain positive on paraffin-embedded tissue after protease digestion (direct immunofluorescence; original magnification ×400). (e) Glomeruli show staining for κ and (f) not λ on the protease-digested, paraffin-embedded tissue (direct immunofluorescence; original magnification ×400).