Fig. 3

Electron microscopy of renal biopsied specimen. Transmission electron microscopy shows electron-dense particles in lysosomes of tubular epithelial cells (red arrow, a: ×8000, b: ×8000, c: ×8000). d, e Light microscopy of Perls’ Prussian blue staining and low vacuum scanning electron microscopy images of the same area, respectively (d: ×1000, e: ×1000). e Red arrows show white electron-dense particles, corresponding to the blue granules in d. Regarding the tubular cells that are not stained blue in d, no electron-dense particles are observed in e. f shows higher magnification image of the red square area in e (f: ×6000). The red arrows indicate electron-dense particles