Polycystic Kidney Disease Basics,Symptoms and Complications

Polycystic kidney disease (PKD) is a genetic disorder characterized by the growth of numerous cysts in the kidneys. The kidneys are two organs, each about the size of a fist, located in the upper part of a person's abdomen, toward the back. The kidneys filter wastes and extra fluid from the blood to form urine. They also regulate amounts of certain vital substances in the body. When cysts form in the kidneys, they are filled with fluid. PKD cysts can profoundly enlarge the kidneys while replacing much of the normal structure, resulting in reduced kidney function and leading to kidney failure.

When PKD causes kidneys to fail-which usually happens after many years-the patient requires dialysis or kidney transplantation. About one-half of people with the most common type of PKD progress to kidney failure, also called end-stage renal disease (ESRD).

PKD can also cause cysts in the liver and problems in other organs, such as blood vessels in the brain and heart. The number of cysts as well as the complications they cause help doctors distinguish PKD from the usually harmless "simple" cysts that often form in the kidneys in later years of life.

Two major inherited forms of PKD exist:

Autosomal dominant PKD is the most common inherited form. Symptoms usually develop between the ages of 30 and 40, but they can begin earlier, even in childhood. About 90 percent of all PKD cases are autosomal dominant PKD.

Autosomal recessive PKD is a rare inherited form. Symptoms of autosomal recessive PKD begin in the earliest months of life, even in the womb.

Polycystic kidney disease symptoms may include:

• High blood pressure
• Back or side pain
• Headache
• Increase in the size of your abdomen
• Blood in your urine
• Frequent urination
• Kidney stones
• Kidney failure

There are numerous complications associated with polycystic kidney disease including:

High blood pressure. Elevated blood pressure is a common complication of polycystic kidney disease. Untreated, high blood pressure can cause further damage to your kidneys and increase your risk of heart disease and stroke.
Loss of kidney function.

Progressive loss of kidney function is one of the most serious complications of polycystic kidney disease. Nearly half of those with the disease have kidney failure by age 60. If you have high blood pressure or blood or protein in your urine, you have a greater risk of kidney failure.

Pregnancy complications. Pregnancy is successful for most women with polycystic kidney disease. In some cases, however, women may develop a life-threatening disorder called preeclampsia. Those most at risk are women who have high blood pressure before they become pregnant.

Growth of cysts in the liver. The likelihood of developing liver cysts for someone with polycystic kidney disease increases with age. While both men and women develop cysts, women often develop larger cysts. Cyst growth may be aided by female hormones.

Development of an aneurysm in the brain. Localized enlargement of an artery in your brain can cause bleeding (hemorrhage) if it ruptures. People with polycystic kidney disease have a higher risk of aneurysm, especially those younger than age 50. The risk is higher if you have a family history of aneurysm or if you have uncontrolled high blood pressure.

Heart valve abnormalities. As many as one-quarter of adults with polycystic kidney disease develop mitral valve prolapse. When this happens, the valve no longer closes properly, which allows blood to leak backward.

Colon problems. Weaknesses and pouches or sacs in the wall of the colon (diverticulosis) may develop in people with polycystic kidney disease.

Chronic pain. Pain is a common symptom for people with polycystic kidney disease. It often occurs in your side or back. The pain can also be associated with a urinary tract infection or a kidney stone.