| Definition: |
An inherited kidney disorder which enlarges the kidneys and interferes with their function because of multiple cysts on the kidneys.
|
| Alternative Names: |
Cysts - kidneys; Kidney - polycystic; Autosomal dominant polycystic kidney disease; ADPKD
|
| Causes, incidence, and risk factors: |
Polycystic kidney disease (PKD) is an inherited disorder (with autosomal dominant inheritance -- if one parent carries the gene, 50% of the children will develop the disorder) where multiple clusters of cysts form on the kidneys. The exact mechanism that triggers cyst formation is unknown.
Cysts in the kidneys are associated with aneurysms of the blood vessels in the brain. They may be associated with diverticula of the colon, and with cysts in the liver, pancreas, and testes. As many as 50% of people with polycystic kidney disease also have cysts on the liver.
In early stages of the disease, the cysts enlarge the kidney and interfere with kidney function, resulting in chronichigh blood pressure, anemia, and kidney infections. The cysts may cause the kidneys to increase production of erythropoietin (the hormone that stimulates production of red blood cells) resulting in increased number of red blood cells, rather than the expected anemia. Bleeding into a cyst can cause flank pain. Kidney stones are more common than in people without the disorder. Hypertension caused by polycystic kidneys may be difficult to control.
The disease is slowly progressive, eventually resulting in end-stage kidney failure. It is also associated with liver disease, including infection of liver cysts. An autosomal recessive form of polycystic kidney disease also exists and appears in infancy or childhood; it tends to be very serious and progresses rapidly, resulting in end-stage kidney failure and causing death in infancy or childhood.
ADPKD occurs in both children and adults, but it is much more common in adults, often not presenting symptoms until middle age. It affects nearly 1 in 1000 Americans. The actual number may be more, as some people do not have symptoms. The disorder may not be discovered unless procedures showing the disease are performed for other reasons.
Risks include a personal or family history of polycystic kidney disease. |
| Signs and tests: |
Examination may show high blood pressure, kidneys or abdominal masses (aggregations of cells) which are felt by touch during examination, abdominal tenderness over the liver (right upper quadrant), and enlarged liver. There may be heart murmurs or other signs of aortic insufficiency or mitral insufficiency.
Polycystic kidney disease, and associated cysts on the liver or other organs, may show on:In a family with several affected members, genetic linkage tests can be performed to determine with fair reliability whether a person at risk carries the gene for ADPKD. |
| Treatment: |
Currently, no treatment can prevent the cysts from forming or enlarging. Treatment goals are the reduction of symptoms and prevention of complications.
Hypertension may be difficult to control, but control of it is the most important aspect of treatment. Treatment may include antihypertensive and/or diuretic medications, low salt diet, or other treatments.
A urinary infection should be treated promptly with appropriate antibiotics.
If there are symptoms of anemia, it may be treated with iron and other supplements, erythropoietin administration, or blood transfusion.
Surgical or radiologic drainage of cysts may be indicated because of pain, bleeding, infection, or obstruction. (There are usually too many cysts to make cyst removal a feasible alternative.)
Surgical removal of one or both kidneys may be required. Treatment of end-stage kidney disease may include kidney dialysis or kidney transplantation. |
| Expectations (prognosis): |
Polycystic kidney disease progresses slowly but persistently. Medical treatment may provide relief of symptoms for many years. Eventual end-stage kidney failure is common.
The absence of systemic disease or autoimmune disease makes people with polycystic kidney disease good candidates for kidney transplantation. |
| Calling your health care provider: |
Call your health care provider if symptoms indicate polycystic kidney disease may be present.
Call for an appointment with your health care provider if there is a family history of polycystic kidney disease or associated disorders and children are planned. Genetic counseling may be offered because of the pattern of inheritance of the disorder. |
| Prevention: |
| Prevention may not be possible. |
|
 |
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is the first of its kind, requiring compliance with 53 standards of quality and accountability, verified by independent audit. A.D.A.M. is among the first to achieve this important distinction for online health information and services. A.D.A.M. is also a founding member of Hi-Ethics (www.hiethics.com) and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).
|
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2003 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
|
