Polycystic kidney diseaseDefinition:
Polycystic kidney disease is a kidney disorder passed down through families in which multiple cysts form on the kidneys, causing them to become enlarged.
Cysts - kidneys; Kidney - polycystic; Autosomal dominant polycystic kidney disease; ADPKD
Causes, incidence, and risk factors:
Polycystic kidney disease (PKD) is passed down through families (inherited), usually as an autosomal dominant trait. If one parent carries the gene, the children have a 50% chance of developing the disorder.
Autosomal dominant PKD occurs in both children and adults, but it is much more common in adults, with symptoms often not showing up until middle age. It affects nearly 1 in 1,000 Americans. The actual number may be more, as some people do not have symptoms. The disorder may not be discovered unless tests revealing the disease are performed for other reasons.
An autosomal recessive form of polycystic kidney disease also exists and appears in infancy or childhood. This type tends to be very serious and progresses rapidly, resulting in end-stage kidney failure and generally causing death in infancy or childhood.
Persons with PKD have multiple clusters of cysts form on the kidneys. The exact action that triggers cyst formation is unknown. In early stages of the disease, the cysts cause the kidney to swell, disrupting kidney function and leading to chronic high blood pressure and kidney infections. The cysts may cause the kidneys to increase production of erythropoietin , a hormone that stimulates production of red blood cells. This leads to too many red blood cells, rather than the anemia seen in chronic kidney disease.
Bleeding in a cyst can cause flank pain . Kidney stones are more common in people with PKD.
PKD is associated with the following conditions:
As many as half of people with PKD have cysts on the liver. A personal or family history of PKD increases your risk for the condition.
Additional symptoms that may be associated with this disease include the following:
Signs and tests:
Examination may show high blood pressure, kidney or abdominal masses, abdominal tenderness over the liver, and enlarged liver .
There may be heart murmurs or other signs of aortic insufficiency or mitral insufficiency .
Those with a personal or family history of PKD should be evaluated to determine if cerebal aneurysms are a cause of headaches.
Polycystic kidney disease and associated cysts on the liver or other organs may be detected with the following tests:
In a family with several members with PKD, genetic tests can be done to determine whether a person at risk carries the PKD gene.
The goal of treatment is to control symptoms and prevent complications. High blood pressure may be difficult to control, but control of it is the most important aspect of treatment.
Treatment may include:
- Blood pressure medicines
- Low-salt diet
Any urinary tract infection should be treated promptly with appropriate antibiotics.
Cysts that are painful, infected, bleeding, or causing an obstruction may need to be drained. (There are usually too many cysts to make 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.
The stress of an illness can often be helped by joining a support group where members share common experiences and problems.
See: Kidney disease - support group
The disease gets worse slowly, eventually resulting in end-stage kidney failure . It is also associated with liver disease , including infection of liver cysts.
Medical treatment may provide relief of symptoms for many years.
The absence of systemic disease or autoimmune disease makes people with polycystic kidney disease good candidates for kidney transplantation.
- High blood pressure
- Recurrent urinary tract infection
- Recurrent kidney infection
- Kidney failure, mild to severe
- End-stage kidney disease
- Bleeding or rupture of cysts
- Infection of liver cysts
- Liver failure, mild to severe
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.
Currently, no treatment can prevent the cysts from forming or enlarging.
In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 128.
In: Kliegman RM, Behrman RE, Jenson HB, Stanton BF, eds. Nelson Textbook of Pediatrics. 18th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 521.