Segmental focal glomerulosclerosis is a histological lesion characterized by podocyte damage. It may be a primary disease linked to an unknown circulating factor, secondary to viral infections, drug toxicity, or a disadaptive response to the loss of nephrons, or it may depend on gene mutations or have an indeterminate cause. The treatment of the primary form involves immunosuppressors. Additional pharmacotherapies for residual proteinuria are used, and emerging therapies are being studied to target other pathological pathways.