Polycystic kidney disease causes numerous cysts (non-cancerous growths) to form in both kidneys. It is a genetic disease, meaning you inherit it from your parents. About 600,000 Americans have polycystic kidney disease.
The kidneys are a pair of bean-shaped organs that sit in the upper part of the abdomen. They filter wastes and extra fluid from the blood, which get passed out of the body in the form of urine. The kidneys also regulate the amount of certain vital substances in the body, such as electrolytes.
When polycystic kidney disease causes numerous cysts to form in the kidneys, the kidneys get severely enlarged, and the cysts also take the place of normal kidney tissue. With less normal kidney tissue, the kidneys cannot function as well, and eventually the kidneys may fail. Cysts normally form in the kidneys as people age, but with polycystic kidney disease there are many more cysts than normal, and they cause problems in the body.
In about half of people with the most common type of polycystic kidney disease, the kidneys eventually fail. When that happens, the patient needs to get a kidney transplant or needs to go on regular dialysis, where a machine acts as the kidney and filters the blood. Usually a person can live with polycystic kidney disease for many years before the kidneys fail.
Though its name makes it sound like it only affects the kidneys, polycystic kidney disease can also cause cysts in the liver and pancreas. It can also cause problems in other organs, such as aneurysms in the brain (bulges in the walls of blood vessels, which can leak and cause a stroke).
There are two major types of polycystic kidney disease:
Autosomal dominant polycystic kidney disease. This is the most common form, making up about 90% of all cases of polycystic kidney disease. If one of your parents has this disease, you have a 50% chance of inheriting it.
Autosomal recessive polycystic kidney disease. This is a rare form of the disease. It can occur when two people who carry the gene for the disease have children. The parents don't have the disease themselves, and probably don't know they are carrying the problematic gene. It only occurs in one-fourth of the children of couples who both carry the gene.