Figure 1.

(a) Global glomerulosclerosis. Although this lesion is not required for the diagnosis of focal segmental glomerulosclerosis, it is frequently present in association with segmental glomerulosclerosis in advanced stages of the disease (Silver, ×200). (b) Segmental glomerulosclerosis involving more than half of the glomerulus with the scarring process associated with adhesion formation with Bowman's capsule in the FSGS, not otherwise specified (NOS) variant (Silver, ×200). (c) Tip variant of FSGS involving the tubular pole (periodic acid-Schiff, ×200). (d) The perihilar location of segmental sclerosis in a case of perihilar FSGS (PAS, ×200)