CD40LG and focal segmental glomerulosclerosis: Focal segmental glomerulosclerosis (FSGS) is a clinicopathological syndrome that usually manifests clinically as nephrotic syndrome and morphologically as focal and segmental glomerular sclerosis under light microscopy (LM), a foot-process effacement under electron microscopy (EM), and occasional immunoglobulin M (IgM) deposits in immunofluorescent (IF) analysis (1-5).