Polycystic Kidney 

Disease 

National Kidney and Urologic Diseases Information Clearinghouse 

National 

Institute of 

Diabetes and 

Digestive 

and Kidney 

Diseases 

NATIONAL 

INSTITUTES 

OF HEALTH 

U.S. Department 

of Health and 

Human Services 

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. 

In the United States, about 600,0001

 people 

have PKD, and cystic disease is the fourth 

leading cause of kidney failure. 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. 

1 Grantham JJ, Nair V, Winklhoffer F. Cystic diseases 

of the kidney. In: Brenner BM, ed. Brenner & 

Rector’s The Kidney. Vol. 2. 6th ed. Philadelphia: 

WB Saunders Company; 2000: 1699–1730. 

Autosomal Dominant PKD 

What is autosomal 

dominant PKD? 

Autosomal dominant PKD is the most common inherited disorder of the kidneys. The 

phrase “autosomal dominant” means that 

if one parent has the disease, there is a 50 

percent chance that the disease gene will 

pass to a child. In some cases—perhaps 10 

percent—autosomal dominant PKD occurs 

spontaneously in patients. In these cases, 

neither of the parents carries a copy of the 

disease gene. 
Many people with autosomal dominant 

PKD live for several decades without 

developing symptoms. For this reason, 

autosomal dominant PKD is often called 

“adult polycystic kidney disease.” Yet, in 

some cases, cysts may form earlier in life 

and grow quickly, causing symptoms in 

childhood. 

Cysts 

Ureter 

Polycystic kidney 

Healthy kidney 

The polycystic kidney roughly retains the same shape as 

the healthy kidney. 

The cysts grow out of nephrons, the tiny 

filtering units inside the kidneys. The cysts 

eventually separate from the nephrons and 

continue to enlarge. The kidneys enlarge 

along with the cysts—which can number 

in the thousands—while roughly retaining their kidney shape. In fully developed 

autosomal dominant PKD, a cyst-filled kidney can weigh as much as 20 to 30 pounds. 

High blood pressure is common and develops in most patients by age 20 or 30. 

What are the symptoms of 

autosomal dominant PKD? 

The most common symptoms are pain in 

the back and the sides—between the ribs 

and hips—and headaches. The pain can be 

temporary or persistent, mild or severe. 

People with autosomal dominant PKD also 

can experience the following complications: 

•	 urinary tract infections—specifically, in 

the kidney cysts 

•	 hematuria—blood in the urine 

•	 liver and pancreatic cysts 

•	 abnormal heart valves 

•	 high blood pressure 

•	 kidney stones 

•	 aneurysms—bulges in the walls of 


blood vessels—in the brain 


•	 diverticulosis—small pouches bulge 

outward through the colon 

How is autosomal dominant 

PKD diagnosed? 

Autosomal dominant PKD is usually 

diagnosed by kidney imaging studies. The 

most common form of diagnostic kidney 

imaging is ultrasound, but more precise 

studies, such as computerized tomography 

(CT) scans or magnetic resonance imaging 

(MRI) are also widely used. In autosomal 

dominant PKD, the onset of kidney damage 

and how quickly the disease progresses can 

vary. Kidney imaging findings can also vary 

considerably, depending on a patient’s age. 

Younger patients usually have both fewer 

and smaller cysts. Doctors have therefore 

developed specific criteria for diagnosing 

2	 Polycystic Kidney Disease 
the disease with kidney imaging findings, 

depending on patient age. For example, 

the presence of at least two cysts in each 

kidney by age 30 in a patient with a family history of the disease can confirm the 

diagnosis of autosomal dominant PKD. If 

there is any question about the diagnosis, a 

family history of autosomal dominant PKD 

and cysts found in other organs make the 

diagnosis more likely. 

In most cases of autosomal dominant 

PKD, patients have no symptoms and their 

physical condition appears normal for 

many years, so the disease can go unnoticed. Physical checkups and blood and 

urine tests may not lead to early diagnosis. 

Because of the slow, undetected progression of cyst growth, some people live for 

many years without knowing they have 

autosomal dominant PKD. 

Once cysts have grown to about one-half 

inch, however, diagnosis is possible with 

imaging technology. Ultrasound, which 

passes sound waves through the body to 

create a picture of the kidneys, is used 

most often. Ultrasound imaging does not 

use any injected dyes or radiation and is 

safe for all patients, including pregnant 

women. It can also detect cysts in the 

kidneys of a fetus, but large cyst growth 

this early in life is uncommon in autosomal 

dominant PKD. 

More powerful and expensive imaging 

procedures such as CT scans and MRI also 

can detect cysts. Recently, MRI has been 

used to measure kidney and cyst volume 

and monitor kidney and cyst growth, which 

may serve as a way to track progression of 

the disease. 

An ultrasound imaging device passes harmless sound 

waves through the body to detect possible kidney cysts. 

Diagnosis can also be made with a genetic 

test that detects mutations in the autosomal dominant PKD genes, called PKD1 

and PKD2. Although this test can detect 

the presence of the autosomal dominant 

PKD mutations before large cysts develop, 

its usefulness is limited by two factors: 

detection of a disease gene cannot predict 

the onset of symptoms or ultimate severity of the disease, and if a disease gene is 

detected, no specific prevention or cure 

for the disease exists. However, a young 

person who knows of a PKD gene mutation 

may be able to forestall the loss of kidney 

function through diet and blood pressure 

control. The genetic test may also be used 

to determine whether a young member of a 

PKD family can safely donate a kidney to a 

family member with the disease. Individuals with a family history of PKD who are of 

childbearing age might also want to know 

whether they have the potential of passing 

a PKD gene to a child. Anyone considering 

genetic testing should receive counseling to 

understand all the implications of the test. 

3 Polycystic Kidney Disease 
How is autosomal dominant 

PKD treated? 

Although a cure for autosomal dominant 

PKD is not available, treatment can ease 

symptoms and prolong life. 

Pain. Pain in the area of the kidneys 

can be caused by cyst infection, bleeding 

into cysts, kidney stone, or stretching of 

the fibrous tissue around the kidney with 

cyst growth. A doctor will first evaluate 

which of these causes are contributing 

to the pain to guide treatment. If it is 

determined to be chronic pain due to cyst 

expansion, the doctor may initially suggest over-the-counter pain medications, 

such as aspirin or acetaminophen (Tylenol). Consult your doctor before taking 

any over-the-counter medication because 

some may be harmful to the kidneys. For 

most but not all cases of severe pain due 

to cyst expansion, surgery to shrink cysts 

can relieve pain in the back and sides. 

However, surgery provides only temporary relief and does not slow the disease’s 

progression toward kidney failure. 

Headaches that are severe or that seem to 

feel different from other headaches might 

be caused by aneurysms—blood vessels 

that balloon out in spots—in the brain. 

These aneurysms could rupture, which can 

have severe consequences. Headaches 

also can be caused by high blood pressure. 

People with autosomal dominant PKD 

should see a doctor if they have severe or 

recurring headaches—even before considering over-the-counter pain medications. 

Urinary tract infections. People with 

autosomal dominant PKD tend to have 

frequent urinary tract infections, which can 

be treated with antibiotics. People with the 

disease should seek treatment for urinary 

tract infections immediately because infection can spread from the urinary tract to 

the cysts in the kidneys. Cyst infections are 

difficult to treat because many antibiotics 

do not penetrate the cysts. 

High blood pressure. Keeping blood pressure under control can slow the effects 

of autosomal dominant PKD. Lifestyle 

changes and various medications can lower 

high blood pressure. Patients should ask 

their doctors about such treatments. Sometimes proper diet and exercise are enough 

to keep blood pressure controlled. 

End-stage renal disease. After many years, 

PKD can cause the kidneys to fail. Because 

kidneys are essential for life, people with 

ESRD must seek one of two options for 

replacing kidney functions: dialysis or 

transplantation. In hemodialysis, blood is 

circulated into an external filter, where it 

is cleaned before re-entering the body; in 

peritoneal dialysis, a fluid is introduced into 

the abdomen, where it absorbs wastes and 

is then removed. Transplantation of healthy 

kidneys into ESRD patients has become 

a common and successful procedure. 

Healthy—non-PKD—kidneys transplanted 

into PKD patients do not develop cysts. 

4 Polycystic Kidney Disease 
Autosomal Recessive PKD 

What is autosomal recessive 

PKD? 

Autosomal recessive PKD is caused by a 

mutation in the autosomal recessive PKD 

gene, called PKHD1. Other genes for the 

disease might exist but have not yet been 

discovered by scientists. We all carry two 

copies of every gene. Parents who do not 

have PKD can have a child with the disease 

if both parents carry one copy of the abnormal gene and both pass that gene copy to 

their baby. The chance of the child having 

autosomal recessive PKD when both parents carry the abnormal gene is 25 percent. 

If only one parent carries the abnormal 

gene, the baby cannot get autosomal recessive PKD but could ultimately pass the 

abnormal gene to his or her children. 

The signs of autosomal recessive PKD 

frequently begin before birth, so it is often 

called “infantile PKD.” Children born 

with autosomal recessive PKD often, but 

not always, develop kidney failure before 

reaching adulthood. Severity of the disease varies. Babies with the worst cases die 

hours or days after birth due to respiratory 

difficulties or respiratory failure. 

Some people with autosomal recessive PKD 

do not develop symptoms until later in 

childhood or even adulthood. Liver scarring occurs in all patients with autosomal 

recessive PKD and tends to become more 

of a medical concern with increasing age. 

What are the symptoms of 

autosomal recessive PKD? 

Children with autosomal recessive PKD 

experience high blood pressure, urinary 

tract infections, and frequent urination. 

The disease usually affects the liver and 

spleen, resulting in low blood cell counts, 

varicose veins, and hemorrhoids. Because 

kidney function is crucial for early physical development, children with autosomal 

recessive PKD and decreased kidney function are usually smaller than average size. 

Recent studies suggest that growth problems may be a primary feature of autosomal 

recessive PKD. 

How is autosomal recessive PKD 

diagnosed? 

Ultrasound imaging of the fetus or newborn 

reveals enlarged kidneys with an abnormal 

appearance, but large cysts such as those in 

autosomal dominant PKD are rarely seen. 

Because autosomal recessive PKD tends 

to scar the liver, ultrasound imaging of the 

liver also aids in diagnosis. 

How is autosomal recessive PKD 

treated? 

Medicines can control high blood pressure 

in autosomal recessive PKD, and antibiotics 

can control urinary tract infections. Eating increased amounts of nutritious food 

improves growth in children with autosomal recessive PKD. In some cases, growth 

hormones are used. In response to kidney 

failure, autosomal recessive PKD patients 

must receive dialysis or transplantation. If 

serious liver disease develops, some people 

can undergo combined liver and kidney 

transplantation. 

5 Polycystic Kidney Disease 
Genetic Diseases 

Genes are segments of DNA, the 

long molecules that reside in each of 

a person’s cells. The genes, through 

complex processes, build proteins for 

growth and maintenance of the body. 

At conception, DNA—or genes—from 

both parents are passed to the child. 

A genetic disease occurs when one or 

both parents pass abnormal genes to 

a child at conception. If receiving an 

abnormal gene from just one parent is enough to produce a disease in 

the child, the disease is said to have 

dominant inheritance. If receiving 

abnormal genes from both parents is 

needed to produce disease in the child, 

the disease is said to be recessive. A 

genetic disease can also occur through 

a spontaneous mutation. 

The chance of acquiring a dominant 

disease is higher than the chance of 

acquiring a recessive disease. A child 

who receives only one gene copy for 

a recessive disease at conception will 

not develop the genetic disease—such 

as autosomal recessive PKD—but 

could pass the gene to the following 

generation. 

Hope Through Research 

Scientists have begun to identify the processes that trigger formation of PKD 

cysts. Advances in the field of genetics 

have increased our understanding of the 

abnormal genes responsible for autosomal 

dominant and autosomal recessive PKD. 

Scientists have located two genes associated with autosomal dominant PKD. The 

first was located in 1985 on chromosome 

16 and labeled PKD1. PKD2 was localized to chromosome 4 in 1993. Within 3 

years, scientists had isolated the proteins 

these two genes produce—polycystin-1 and 

polycystin-2. 

When both the PKD1 and PKD2 genes are 

normal, the proteins they produce work 

together to foster normal kidney development and inhibit cyst formation. A mutation in either of the genes can lead to cyst 

formation, but evidence suggests that 

disease development also requires other 

factors, in addition to the mutation in one 

of the PKD genes. 

Genetic analyses of most families with PKD 

confirm mutations in either the PKD1 or 

PKD2 gene. In about 10 to 15 percent of 

cases, however, families with autosomal 

dominant PKD do not show obvious abnormalities or mutations in the PKD1 and 

PKD2 genes, using current testing methods. 

Researchers have also recently identified 

the autosomal recessive PKD gene, called 

PKHD1, on chromosome 6. Genetic testing for autosomal recessive PKD to detect 

mutations in PKHD1 is now offered by a 

limited number of molecular genetic diagnostics laboratories in the United States. 

6 Polycystic Kidney Disease 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Researchers have bred rodents with a 

genetic disease that parallels both inherited forms of human PKD. Studying these 

mice will lead to greater understanding of 

the genetic and nongenetic mechanisms 

involved in cyst formation. In recent years, 

researchers have discovered several compounds that appear to inhibit cyst formation in mice with the PKD gene. Some of 

these compounds are in clinical testing in 

humans. Scientists hope further testing will 

lead to safe and effective treatments for 

humans with the disease. 

Recent clinical studies of autosomal 

dominant PKD are exploring new imaging 

methods for tracking progression of cystic kidney disease. These methods, using 

MRI, are helping scientists design better 

clinical trials for new treatments of autosomal dominant PKD. 

People interested in participating in clinical trials of new treatments for PKD can 

find a list of centers recruiting patients at 

www.ClinicalTrials.gov. 

You may also find additional information on this topic 

using the following databases: 

The NIDDK Reference Collection is a collection 


of thousands of materials produced for patients 


and health care professionals, including fact sheets, 


brochures, and audiovisual materials. Visit 


www.catalog.niddk.nih.gov/resources.
 

MedlinePlus brings together a wealth of information 

from the National Library of Medicine, the National 

Institutes of Health, and other government agencies 

and health-related organizations. MedlinePlus offers 

easy access to medical journal articles, a medical 

dictionary and medical encyclopedia, health information in Spanish, hospital and physician directories, 

drug and supplement lists, interactive patient tutorials, links to hundreds of clinical trials, and the latest 

health news. Visit www.medlineplus.gov. 

Points to Remember 

The two forms of polycystic kidney disease 

(PKD) are 

•	 autosomal dominant PKD, a form that 

usually causes symptoms in adulthood 

•	 autosomal recessive PKD, a rare 

form that usually causes symptoms in 

infancy and early childhood 

The symptoms and signs of PKD include 

•	 pain in the back and lower sides 

•	 headaches 

•	 urinary tract infections 

•	 blood in the urine 

• cysts in the kidneys and other organs 

Diagnosis of PKD is obtained by 

•	 ultrasound imaging of kidney cysts 

•	 ultrasound imaging of cysts in other 

organs 

•	 family medical history, including 


genetic testing 


PKD has no cure. Treatments include 

•	 medicine to control high blood 


pressure
 

•	 medicine and surgery to reduce pain 

•	 antibiotics to resolve infections 

•	 dialysis to replace functions of failed 

kidneys 

•	 kidney transplantation 

7	 Polycystic Kidney Disease 
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

For More Information 

Polycystic Kidney Disease Foundation 

9221 Ward Parkway, Suite 400 

Kansas City, MO 64114–3367 

Phone: 1–800–PKD–CURE (753–2873) or 

816–931–2600 

Email: pkdcure@pkdcure.org 

Internet: www.pkdcure.org 

American Association of Kidney Patients 

3505 East Frontage Road, Suite 315 

Tampa, FL 33607 

Phone: 1–800–749–2257 or 813–636–8100 

Email: info@aakp.org 

Internet: www.aakp.org 

National Kidney Foundation 

30 East 33rd Street 

New York, NY 10016 

Phone: 1–800–622–9010 or 212–889–2210 

Internet: www.kidney.org 

National Kidney and 

Urologic Diseases 

Information Clearinghouse 

3 Information Way 

Bethesda, MD 20892–3580 

Phone: 1–800–891–5390 

Fax: 703–738–4929 

Email: nkudic@info.niddk.nih.gov 

Internet: www.kidney.niddk.nih.gov 

The National Kidney and Urologic Diseases 

Information Clearinghouse (NKUDIC) is a 

service of the National Institute of Diabetes 

and Digestive and Kidney Diseases (NIDDK). 

The NIDDK is part of the National Institutes 

of Health of the U.S. Department of Health 

and Human Services. Established in 1987, the 

Clearinghouse provides information about 

diseases of the kidneys and urologic system to 

people with kidney and urologic disorders and 

to their families, health care professionals, and 

the public. The NKUDIC answers inquiries, 

develops and distributes publications, and works 

closely with professional and patient organizations and Government agencies to coordinate 

resources about kidney and urologic diseases. 

Publications produced by the Clearinghouse 

are carefully reviewed by both NIDDK scientists and outside experts. This publication was 

reviewed by Lisa Guay-Woodford, M.D., University of Alabama at Birmingham, and Stefan 

Somlo, M.D., Yale University. 

This publication is not copyrighted. The 

Clearinghouse encourages users of this publication to 

duplicate and distribute as many copies as desired. 

This fact sheet is also available at 

www.kidney.niddk.nih.gov. 

The U.S. Government does not endorse or favor any 

specific commercial product or company. Trade, 

proprietary, or company names appearing in this 

document are used only because they are considered 

necessary in the context of the information provided. 

If a product is not mentioned, the omission does not 

mean or imply that the product is unsatisfactory. 

This publication may contain information about 

medications used to treat a health condition. When 

this publication was prepared, the NIDDK included 

the most current information available. Occasionally, new information about medication is released. 

For updates or for questions about any medications, 

please contact the U.S. Food and Drug Administration at 1–888–INFO–FDA (463–6332), a toll-free call, 

or visit their website at www.fda.gov. Consult your 

doctor for more information. 

U.S. DEPARTMENT OF HEALTH 

AND HUMAN SERVICES 

National Institutes of Health 

NIH Publication No. 08–4008 

November 2007