Introduction
Kidney disease is a very broad term and includes dozens of kidney disorders and hundreds if not thousands of diseases affecting the kidney. Kidney doctors spend years learning about them and they need to keep all of them in the back of their mind when they are working up your kidney problem.Commonly Considered or Diagnosed
Despite the large number of kidney diseases, there tends to be a limited number that are commonly considered or diagnosed. Here are the most important ones:- Diabetic Nephropathy: One of the most common diseases affecting the glomerulus. It is a major cause of kidney failure requiring dialysis. It usually presents with protein in the urine after having had diabetes for many years.
- Hypertensive Nephrosclerosis: The leading cause of kidney failure in African Americans and a significant factor in other racial groups. It is thought that long-standing or very high blood pressure damages the small vessels in the kidney ("nephron") and leads to scarring (“sclerosis”).
- Polycystic Kidney Disease: A genetic disorder where there is a growth of many cysts (“polycystic”). Over many years, the kidneys become replaced with these useless cysts and the kidneys usually fail.
- Lupus Nephritis: Inflammation of the kidneys caused by antibodies (lupus autoantibodies) depositing in the glomeruli. Usually requires a kidney biopsy to diagnose it and decide how aggressively to treat it.
- IgA Nephropathy (Berger’s Disease): Inflammation of the kidneys caused by depositing of a specific type of antibody (immunoglobulin A or IgA) in the glomeruli. Usually presents with a small amount of blood in the urine.
- Minimal Change Disease: A disease of the glomeruli causing a large amount of protein in the urine (nephrotic syndrome). The kidney biopsy usually shows “minimal” findings when viewed by a light microscope. It usually occurs in children and often responds to steroids. It can be seen in adults as well.
- Membranous Nephropathy: The most common cause of nephrotic syndrome in people without diabetes. It is caused by depositing of immune system products in a certain part of the glomerular basement membrane. Why the antibodies are made is not usually known, but sometimes it is due cancer, lupus, viruses, or certain drugs.
- Focal Segmental Glomerulosclerosis (FSGS): A scarring (“sclerosis”) disease that affects only some glomeruli (“focal”) and in only some parts (“segmental”). Usually presents with protein in the urine and usually causes kidney failure after 5 to 20 years.