Polycystic Kidney Disease
Polycystic kidney disease (also called PKD). PKD is an inherited kidney disorder. It causes numerous cysts to grow in the kidneys. These cysts are filled with fluid. If too many cysts grow or if they get too big, the kidneys can become damaged. PKD may impair kidney function and eventually cause kidney failure. PKD is the fourth leading cause of kidney failure.
- Polycystic kidney disease (PKD) causes cysts to form on the kidneys.
- There are three types of PKD: autosomal dominant PKD, autosomal recessive PKD, and acquired cystic kidney disease.
- There is no cure for PKD, but there are treatments that can control symptoms.
Other organs besides the kidney are affected by PKD
PKD can affect other organs besides the kidney. People with PKD may have cysts in their liver, pancreas, spleen, ovaries, and large bowel. Cysts in these organs usually do not cause serious problems, but can in some people. PKD can also affect the brain or heart. If PKD affects the brain, it can cause an aneurysm. An aneurysm is a bulging blood vessel that can burst, resulting in a stroke or even death. If PKD affects the heart, the valves can become floppy, resulting in a heart murmur in some patients.
Many people live with PKD for years without experiencing symptoms associated with the disease. Cysts typically grow 0.5 inches or larger before a person starts noticing symptoms. Initial symptoms associated with PKD can include:
- pain or tenderness in the abdomen
- blood in the urine
- frequent urination
- pain in the sides
- urinary tract infection (UTI)
- kidney stones
- pain or heaviness in the back
- skin that bruises easily
- pale skin color
- joint pain
- nail abnormalities
Children with autosomal recessive PKD may have symptoms that include:
- high blood pressure
- frequent urination
Symptoms in children may resemble other disorders. It is important to get medical attention for a child experiencing any of symptoms listed above.
CausesAbnormal genes cause polycystic kidney disease, and the genetic defects mean the disease runs in families. Rarely, a genetic mutation can be the cause of polycystic kidney disease.
There are two types of polycystic kidney disease, caused by different genetic flaws:
- Autosomal dominant polycystic kidney disease (ADPKD). Signs and symptoms of ADPKD often develop between the ages of 30 and 40. In the past, this type was called adult polycystic kidney disease, but children can develop the disorder.
Only one parent needs to have the disease in order for it to pass along to the children. If one parent has ADPKD, each child has a 50 percent chance of getting the disease. This form accounts for about 90 percent of cases of polycystic kidney disease.
- Autosomal recessive polycystic kidney disease (ARPKD). This type is far less common than is ADPKD. The signs and symptoms often appear shortly after birth. Sometimes, symptoms don’t appear until later in childhood or during adolescence.
Both parents must have abnormal genes to pass on this form of the disease. If both parents carry a gene for this disorder, each child has a 25 percent chance of getting the disease.
To diagnose all three types of PKD, your doctor may use imaging tests to look for cysts of the kidney, liver, and other organs. Imaging tests used to diagnose PKD include:
- abdominal ultrasound: a non-invasive test that uses sound waves to look at your kidneys for cysts
- abdominal CT scan: can detect smaller cysts in the kidneys
- abdominal MRI scan: uses strong magnets to image your body to visualize kidney structure and look for cysts
- intravenous pyelogram: uses a dye to make your blood vessels show up more clearly on an X-ray
Does everyone with PKD develop kidney failure?
No. About 50 percent of people with PKD will have kidney failure by age 60, and about 60 percent will have kidney failure by age 70. People with kidney failure will need dialysis or a kidney transplant. Certain people have an increased risk of kidney failure including:
- patients with high blood pressure
- patients with protein or blood in their urine
- women with high blood pressure who have had more than three pregnancies
Some of the treatment options may include:
- pain medication, except Ibuprofen, which is not recommended as it may worsen kidney disease
- blood pressure medication
- antibiotics to treat UTIs
- a low sodium diet
- diuretics to help remove excess fluid from the body
- surgery to drain cysts and help relieve discomfort
With advanced PKD that causes renal failure, dialysis and kidney transplant may be necessary. One or both of the kidneys may need to be removed.