Polycystic kidney disease

Answer 1

Definition

Polycystic kidney disease is a kidney disorder passed down through families in which multiple cysts form on the kidneys, causing them to become enlarged.

Alternative Names

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:

• Brain aneurysms
• Cysts in the liver, pancreas, and testes
• Diverticula of the colon

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.

Symptoms

• Abdominal painor tenderness
• Blood in the urine
• Excessive urination at night
• Flank pain on one or both sides

Additional symptoms that may be associated with this disease include the following:

• Drowsiness
• High blood pressure
• Joint pain
• Nail abnormalities
• Painful menstruation

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.

• A urinalysismay show urine protein or blood in the urine.
• A CBC may show decreased or increased RBCs and hematocrit.
• Cerebral angiography may show associated aneurysms.

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:

• Abdominal ultrasound
• Abdominal CT scan
• Abdominal MRIscan
• IVP

In a family with several members with PKD, genetic tests can be done to determine whether a person at risk carries the PKD gene.

Treatment

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
• Diuretics
• 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.

Support Groups

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

Expectations (prognosis)

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.

Complications

• High blood pressure
• Anemia
• Recurrent urinary tract infection
• Recurrent kidney infection
• Kidney stones
• 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.

Prevention

Currently, no treatment can prevent the cysts from forming or enlarging.

References

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.

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Answer 2

Definition

Polycystic kidney disease is a kidney disorder passed down through families in which many cysts form in the kidneys, causing them to become enlarged.

Alternative Names

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. Symptoms often do not appear until middle age. It affects nearly 1 in 1,000 Americans. The actual number may be more, because some people do not have symptoms.

An autosomal recessive form of PKD also exists. It appears in infancy or childhood. This form is much less common than autosomal dominant PKS, but it tends to be very serious and gets worse quickly. It can cause serious lung and liver disease, end-stage kidney disease, and it usually causes death in infancy or childhood.

Persons with PKD have many clusters of cysts in the kidneys. What exactly triggers the cysts to form is unknown.

PKD is associated with the following conditions:

• Aortic aneurysms
• Brain aneurysms
• Cysts in the liver, pancreas, and testes
• Diverticula of the colon

As many as half of people with PKD have cysts on the liver. A family history of PKD increases your risk for the condition.

Symptoms

• Abdominal painor tenderness
• Blood in the urine
• Excessive urination at night
• Flank pain on one or both sides

Other symptoms that may occur with this disease include:

• Drowsiness
• Joint pain
• Nail abnormalities

Signs and tests

An examination may show:

• Abdominal tenderness over the liver
• Enlarged liver
• Heart murmursor other signs of aortic insufficiency or mitral insufficiency
• High blood pressure
• Growths in the kidneys or abdomen

Tests that may be done include:

• Cerebral angiography
• Complete blood count (CBC)
• Urinalysis

People with a personal or family history of PKD should be tested to determine if cerebral aneurysms are causing headaches.

Polycystic kidney disease and cysts on the liver or other organs may be found with the following tests:

• Abdominal CT scan
• Abdominal MRIscan
• Abdominal ultrasound
• Intravenous pyelogram (IVP)

If several members of your family have PKD, genetic tests can be done to determine whether you carry the PKD gene.

Treatment

The goal of treatment is to control symptoms and prevent complications. High blood pressure may be hard to control, but controlling it is the most important part of treatment.

Treatment may include:

• Blood pressure medicines
• Diuretics
• Low-salt diet

Any urinary tract infection should be treated quickly with antibiotics.

Cysts that are painful, infected, bleeding, or causing a blockage may need to be drained. There are usually too many cysts to make it practical to remove each cyst.

Surgery to remove one or both kidneys may be needed. Treatments for end-stage kidney disease may include dialysis or a kidney transplant.

Support Groups

You can often ease the stress of an illness by joining a support group where members share common experiences and problems.

See: Kidney disease - support group

Expectations (prognosis)

The disease gets worse slowly. Eventually it leads to end-stage kidney failure. It is also associated with liver disease, including infection of liver cysts.

Medical treatment may relieve symptoms for many years.

People with PKD who don't have other diseases may be good candidates for a kidney transplant.

Complications

• Anemia
• Bleeding or rupture of cysts
• Chronic kidney disease
• End-stage kidney disease
• High blood pressure
• Infection of liver cysts
• Kidney stones
• Liver failure (mild to severe)
• Repeated urinary tract infections

Calling your health care provider

Call your health care provider if:

• You have symptoms of PKD
• You have a family history of polycystic kidney disease or related disorders and you are planning to have children (you may want to have genetic counseling)

Prevention

Currently, no treatment can prevent the cysts from forming or enlarging.

References

Amaout MA. Cystic kidney diseases. In: Goldman L, Ausiello D, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 128.

Porter CC, Avner Ed. Anatomic abnormalities associated with hematuria. In: Kliegman RM, Stanton BF, St. Geme JW III, Schor NF, Behrman RE, eds. Nelson Textbook of Pediatrics. 19th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 515.

Torres VE, Grantham JJ. Cystic diseases of the kidney. In: Brenner BM, ed. Brenner and Rector's the Kidney. 8th ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 41.

Reviewed By

Review Date: 09/20/2011

David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Herbert Y. Lin, MD, PhD, Nephrologist, Massachusetts General Hospital; Associate Professor of Medicine, Harvard Medical School. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.