RPGN: Crescents

• Crescentic glomerulonephritis. The hypercellular circumferential crescent (arrows) is compressing the glomerular tuft in the center of the glomerulus and closing the capillary lumens.

• Normal glomerulus. There are only 1 or 2 cells per capillary tuft, the capillary lumens are open, the thickness of the glomerular capillary wall (long arrow) is similar to that of the tubular basement membranes(short arrow), and the mesangial cells and mesangial matrix are located in the central or stalk regions of the tuft (arrows).

• Courtesy of Helmut Rennke, MD.