Understanding Polycystic Kidney Disease

Polycystic kidney disease (PKD) is a chronic genetic disorder that causes fluid-filled cysts to grow on kidneys. While many people develop harmless cysts on their kidneys later in life, PKD cysts are different. They tend to be large enough and numerous enough that they can affect kidney function, and even change the shape of your kidney. A normal kidney is about the size of a fist. PKD can cause kidneys to grow to the size of a football.

PKD affects over 12 million people worldwide and is the fourth-leading cause of kidney failure. The condition affects people of all races and ethnicities, occurring in both women and men equally.

What are the symptoms of polycystic kidney disease?

PKD can cause several symptoms, including high blood pressure, blood in urine and pain in the lower back. High blood pressure occurs in about 60-70% of people with PKD, and it’s often one of the first noticeable polycystic kidney disease symptoms. When cysts form on your kidneys, they press on the surrounding blood vessels. Your kidneys start getting less blood, mimicking the circumstances of low blood pressure. In response, your body starts releasing substances that tighten blood vessels, causing blood pressure to rise even higher.

High blood pressure is a leading cause of chronic kidney disease (CKD) on its own. So, managing blood pressure is very important to managing your kidney health. If left untreated, kidney damage from high blood pressure can add to the damage caused by PKD cysts.

Most symptoms of polycystic kidney disease relate to the kidneys, urinary tract and abdomen.

In addition to high blood pressure, common symptoms of PKD include:

Blood in your urine
Pain or feelings of heaviness in your lower back or side
Progressive kidney damage or eventual renal failure
Frequent urinary tract infections
Headaches
Kidney stones
Cysts on other organs, in addition to kidney cysts

Can PKD cause kidney failure?

Nearly half of people with PKD experience kidney failure before the age of 60. However, not everyone with PKD will experience kidney failure over their lifetime. Following proper treatment as prescribed by your doctor may help you reduce your risks, so it’s important to follow treatment instructions exactly and take all medication as directed.

Factors that may increase the risk of kidney failure with PKD include:

Being a male
Having high blood pressure
Being a female with high blood pressure and having 3 or more children

If you have PKD and you are diagnosed with kidney failure, you have treatment options that help you live well and thrive. Discuss treatment options, including dialysis or a kidney transplant, with your doctor to determine what’s right for you.

How is PKD diagnosed?

The most common, affordable, and non-invasive way to detect PKD is with an ultrasound of your kidneys. Your doctor may also order other types of medical imaging, like a CT scan or an MRI.

There is an DNA test for PKD available, though it’s expensive and occasionally fails to detect PKD in people who have it. If you have a family history of PKD, however, the DNA test is 99% accurate. When imaging tests don’t provide conclusive results, genetic testing may be an option to discuss with your doctor. The PKD DNA test is also sometimes used to screen people with a family history of PKD for the disease before they opt to start a family or start the process of donating a kidney to a family member with kidney failure.

Are there different types of PKD?

There are 3 types of polycystic kidney diseases. Autosomal dominant polycystic kidney disease is the most common by far, making up 90% of PKD cases.

Autosomal dominant polycystic kidney disease (ADPKD)—usually presents symptoms between the ages of 30 and 40. It used to be called “adult polycystic kidney disorder,” though ADPKD can also be experienced in childhood. When one parent has the mutated gene that causes ADPKD, then each child has a 50% chance of inheriting it.
Autosomal recessive polycystic kidney disease (ARPKD)—is the rarest type, requiring both parents to carry the gene. Each child has a 25% chance of having the disease. The symptoms are often severe and life-threatening, beginning as early as in the womb.
Acquired Cystic Kidney Disease—may occur in both children or adults who have chronic kidney disease or end stage renal disease (ESRD), with cysts most likely in people who are on dialysis. Unlike other types of PKD, the condition is caused by CKD or ESRD, not inherited. Risk f ACKD increases with the number of years on dialysis treatment.

How is PKD treated?

While there is no cure for PKD, there are things you can do that can help to slow its progression and manage the symptoms.

Manage blood pressure. Reducing high blood pressure can help prevent further kidney damage and help you preserve your health while living with PKD.
Manage your salt intake. While there's no specific polycystic kidney disease diet, managing your salt intake can help put less stress on your kidneys.
Get urinary tract infections (UTIs) treated immediately. See your doctor if you suspect a UTI or any type of infection.
Discuss cyst decompression surgery. While the procedure doesn't affect kidney function, it can provide pain relief in extreme cases of PKD.
Follow your PKD treatment plan exactly as prescribed. Your doctor may also prescribe medications. If you are diagnosed with kidney failure, you will need dialysis or a kidney transplant.
Talk to your doctor about all medications you’re taking. Discuss all medications prescribed by other doctors, as well as any over-the-counter medications you take—especially pain relievers, non-steroidal anti-inflammatory drugs (NSAIDs), herbal supplements or vitamins. Some medications can be harmful to your kidneys.
Discuss newly emerging new treatments for PKD. The FDA recently approved the first-ever medication to treat ADPKD, the most common form of PKD. Called tolvaptan, the medication binds to receptors in the kidneys, blocking the hormones that cause cyst growth to slow progression. Your doctor can tell if it’s right for you.