C3 and ganglioneuroma: In their proposed criteria, at least three of the following five items are required for the diagnosis of IRGN: (1) clinical or laboratory evidence of infection preceding or at the onset of GN, (2) depressed serum complement, (3) endocapillary proliferative and exudative GN, (4) C3-dominant or codominant glomerular IF staining, and (5) “hump”-shaped subepithelial deposits on electron microscopy.