Causes

A change (mutation) in your genes causes PKD. Genes are part of your cells that contain DNA and tell your cells what to do. DNA is found inside every cell in our body and carries information that gets passed from one generation to the next. DNA codes for different traits, such as eye color, body type and sex.

PKD is almost always passed down from a parent or from both parents to their child. There is no way to prevent either type of PKD.

If you have a blood relative with PKD, you are more likely to have PKD or carry the changed gene that causes it (this is called a “carrier”). A carrier means that you have one copy of the gene that causes PKD and could pass the gene to your biological children, but do not have PKD yourself. It is possible to be a carrier of the gene that causes autosomal recessive PKD. It is not possible to be a carrier of the gene that causes ADPKD–you only need to have one copy of this gene to have ADPKD.

Symptoms

Symptoms usually start when you are between 30 and 50 years old. Symptoms include:

• Pain in your back and sides
• Headaches
• Blood in your urine (pee)
• High blood pressure
• UTIs (urinary tract infections)
• Kidney stones

If you have any of these symptoms or a blood relative with PKD, talk with your doctor.

Treatments

Autosomal dominant polycystic kidney disease (ADPKD) leads to kidney failure due to continued enlargement of the cysts in the majority of patients, typically by the sixth decade of life. Treatment focuses on slowing the progression of kidney failure and treating the associated features of the disease, such as kidney infections or kidney stones and flank or abdominal pain.

High blood pressure — Treating high blood pressure can have a dual benefit in people with PKD because it can help prevent cardiovascular disease and also reduce the likelihood of developing kidney failure. For individuals under 50 years of age and with relatively intact kidney function (estimated GFR >60 mL/min/1.73 m²), blood pressures less than 110/75 mmHg are recommended.

Angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) can effectively lower blood pressure in most people with ADPKD. (See “Patient education: High blood pressure treatment in adults (Beyond the Basics)”.)

Low-salt diet — The amount of salt (sodium) ingested on a daily basis has been linked to more rapid progression of kidney disease in patients with ADPKD. It can also raise blood pressure levels. For those reasons, a sodium intake of <2 g (2000 mg) per day is recommended.

Weight control — Patients who are overweight (a body mass index [BMI] of 25 to 30) and patients with obesity (BMI greater than 30) have faster progression of kidney disease in ADPKD. Thus, we recommend keeping a healthy BMI (<25).

Dietary protein restriction — There are conflicting findings on the benefit of a low-protein diet in people with ADPKD. Given the limited evidence of benefit, we do not recommend restricting protein intake below 0.8 g/kg of body weight per day. In this example, a 180 pound (82 kg) man would need approximately 66 grams of protein per day.

Tolvaptan — Tolvaptan is a type of drug called a vasopressin receptor antagonist. It has been shown to slow the decline in kidney function and reduce pain symptoms in people with ADPKD. The use of tolvaptan should be considered in patients who are at risk of rapid progression based on their kidney size for a given age and on their kidney function. Even though tolvaptan does not cure or reverse PKD, it may increase the kidney life span by seven to eight years if it is started early in life. Tolvaptan can cause side effects including liver problems (in about 4 percent of people), so frequent monitoring of the liver function tests (by blood draws) is needed. Most often, patients experience frequent urination, urination at night, and increased thirst.

End-stage kidney disease — Patients with ADPKD who progress to end-stage kidney disease require either dialysis or kidney transplantation. (See “Patient education: Dialysis or kidney transplantation — which is right for me? (Beyond the Basics)”.)

People with ADPKD who require dialysis are usually treated with hemodialysis. People with ADPKD who have hemodialysis appear to survive longer than people with other types of end-stage kidney disease.

Peritoneal dialysis, a form of dialysis that involves infusing fluid into the abdomen and then draining the fluid, is less commonly performed due to the presence of the enlarged kidneys but can be considered on an individual basis. (See “Patient education: Hemodialysis (Beyond the Basics)”.)

The prognosis after kidney transplantation is usually excellent.

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