GN in the adolescent requires prompt diagnosis. When even mild degrees of renal insufficiency are documented, immediate referral to a nephrologist is necessary to ensure that serious conditions, such as RPGN, are correctly diagnosed and aggressively managed. In an adolescent with macroscopic hematuria, the demonstration of dysmorphic RBCs, RBC casts, and proteinuria indicates that the bleeding is of glomerular origin. Physicians caring for adolescents with chronic GN should have a basic understanding of the specific disorders. They may be involved in blood pressure monitoring and should be aware of the potential side effects of the antihypertensive and immunosuppressive medications used in patients with GN.