Polycystic kidney disease, autosomal dominant (ADPKD)

Introduction

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic condition that causes multiple cysts to develop on the kidneys. Cysts are small sacs that are filled with fluid.

The symptoms of ADPKD tend not to begin until adulthood, usually between the ages of 30 and 60.

Symptoms can include:

  • high blood pressure (hypertension)
  • abdominal pain
  • blood in the urine (haematuria)

The symptoms of ADPKD can range from mild to severe.

The kidneys

The kidneys are two bean-shaped organs that are located on either side of the body, just underneath the ribcage.

The main role of the kidneys is to filter out waste products from the blood before converting them into urine. The kidneys also play another important role in helping to maintain blood pressure at a healthy level.

How common is ADPKD?

In general terms, ADPKD is uncommon as only 1 in every 1,000 people are born with the condition.

However, ADPKD is the most common genetic condition to affect the kidneys. It is estimated that around 50,000 people in the UK currently have ADPKD symptoms or will develop it at some time.

The genetics of ADPKD

ADPKD is caused by a genetic mutation that disrupts the normal development of the kidneys. A genetic mutation occurs when the normal instructions that are carried in certain genes become ‘scrambled’.

Two genetic mutations are known to cause ADKPD:

  • PKD1, which accounts for 85% of cases
  • PKD2, which accounts for 15% of cases

Both of the sub-types of ADKPD have the same symptoms, although PKD1 tends to cause more severe symptoms.

Outlook

There is currently no cure for ADPKD. Treatment focuses on helping to relieve the various symptoms and complications that are associated with the condition, such as high blood pressure (hypertension).

The outlook for ADPKD is relatively poor in the long-term. Progressive damage to the kidneys can occur, and this can result in the kidneys losing all or nearly all their functions. This is known as kidney failure or end-stage renal disease.

Almost all people with the PKD1 will have kidney failure by the time they are 70 years old. The average age of kidney failure is 54.

The outlook for people with PKD2 is slightly better. Only half of people with this form of the condition have kidney failure. The average age of kidney failure is 74.

Dialysis or a kidney transplant is the only way of keeping someone with a kidney failure alive. Dialysis is a type of treatment that involves replicating many of the kidney’s functions, such as their blood filtering abilities.

Another serious problem facing people with ADPKD is that the high blood pressure associated with the condition increases their risk of developing cardiovascular disease (CVD). CVD is any sort of condition that affects the heart or circulation of the blood, such as:

  • blood clot  – blood clots are clumps of hardened blood that can develop inside a blood vessel or organ
  • stroke – where the supply of blood to the brain is blocked, potentially putting a person at risk of serious brain damage
  • heart attack  – where the supply of blood to heart is blocked, causing damage to the heart muscle  


Glossary

Abdomen
The abdomen is the part of the body between the chest and the hips.

Blood
Blood supplies oxygen to the body and removes carbon dioxide. It is pumped around the body by the heart.

Cysts
A cyst is a fluid-filled sac or cavity in the body.

Genetic
Genetic is a term that refers to genes- the characteristics inherited from a family member.

Kidney
Kidneys are a pair of bean-shaped organs located at the back of the abdomen, which remove waste and extra fluid from the blood and pass them out of the body as urine.

Spine
The spine supports the skeleton, and surrounds and protects the delicate spinal cord and nerves. It is made up of 33 bones called the vertebrae.

Last updated: 12 June 2012

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