EdrenINFO > Polycystic kidneys (PKD) > More info on PKD
What happens in polycystic kidney disease?
Polycystic kidney disease (often shortened to PKD or PCKD) is the commonest inherited cause of kidney failure. It may be inherited from either your mother or your father. Sometimes they will not know that they carry the disease. Not everyone with PKD gets trouble from their kidneys.
Can anything else cause kidney cysts?
It is quite common for healthy people to have one or two cysts, and occasionally people may have several. But when the kidneys are enlarged and filled with many cysts, PKD is the most likely diagnosis. There are some other rare diseases that very occasionally cause many kidney cysts.
Infantile polycystic kidney disease is rare, causes liver damage as well as kidney trouble, and unfortunately often leads to affected children dying when they are young. It is not the same as the disease that occurs in adults.
Up to top
What kidney trouble does PKD cause?
Almost all patients with PKD have high blood pressure – this is a problem with many kidney diseases. They often have abnormal urine tests also.
About 50% of patients require dialysis or a kidney transplant at some time in their lives. In some families this is often in middle age, in others it usually happens in old age, if at all. If you have many cysts when you are very young, renal failure is more likely.
The cysts may cause pain if there is bleeding into them, and sometimes they may become infected, requiring antibiotic treatment. Very large kidneys may cause discomfort just because of their size. Occasionally bleeding may occur into the urine which may look dramatic, but usually settles spontaneously.
|
||||||||
NormalWhat else can PKD do?
Cerebral aneurysms Some people with PKD develop weaknesses of blood vessels beneath the brain, which develop into aneurysms (swellings) that can rupture to cause a subarachnoid haemorrhage. It is not clear at the moment whether there is anything that can be done to prevent this. New techniques for examining the blood vessels are under investigation – but even if found, it may not be clear how best to treat them (other than by controlling blood pressure). Treatment for any aneurysms that are found carries significant risks. Screening is therefore only suggested if a close family member has had a subarachnoid haemorrage.
Kidney stones People with PKD get more kidney stones than others. It is not known why. The diagnosis may be hard to make, because PKD patients may often have blood in their urine on testing, and they have other reasons for pain in the region of the kidneys.
Other People with PKD are more likely to develop hernias. This can be a problem on peritoneal dialysis. Diverticular disease of the colon is more common. And there seems to be an increased rate of 'floppiness' of one of the heart valves, although this is rarely important.
Up to top
How can family members tell whether they have the disease?
First signs of the disease usually occur in early adult life. There may be abnormalities in the urine on testing, and high blood pressure. But the simplest test is an ultrasound examination, which does not involve exposure to X-rays or any discomfort. This can show cysts developing. If it shows a lot of cysts, you definitely have the disease. Unfortunately, because the cysts develop very slowly in some people, a negative result does not prove that you do not have the disease until you are over at least 20 years, or even later. However the later you develop cysts, the less likely they are to cause you any serious health problems. Other types of scan, such as a CT or MRI scan, may help if there is uncertainty.
Can I have genetic testing?
Genetic testing uses a person's own DNA to identify whether they have inherited a particular condition or gene. The genes involved in PKD are large and complicated, and it is difficult to find out the problem. However tests may be available for some people - this is a common disease, so scientists are working to improve the testing for it, and it is likely that tests will improve quite quickly.
When tests can be done, often they are not foolproof. They work best if you have a family with several affected members.
If you have several affected people in the family, it may be possible to use simpler genetic tests to show whether people have probably (not definitely) inherited the disease. But looking for cysts may be a quicker way to show that you have it (not seeing cysts isn't a definite negative until you are about 30).
Will it ever be cured?
That looks a tall order. However several trials of new treatments to slow down the growth of cysts are getting under way now. All of these are likely to have some risks and possible side effects. In the UK most trials will be organised through renal units. Some of the links at the foot of this page may give further information.
Up to top
How is it treated?
Blood pressure is high for life unless it is treated in most people with PKD. High blood pressure can have serious effects on the heart and blood vessels. It should be treated for this reason.
If there is chronic renal failure (CKD), this should be looked after in the usual way.
Infected cysts occur uncommonly but need antibiotic treatment when they do. Sometimes the big kidneys are uncomfortable, and occasionally bleeding into a cyst can cause pain, but severe continuing pain is uncommon. If it occurs often it needs to be managed cautiously, or high intake of painkillers may cause new problems.
If kidney failure occurs, dialysis and transplantation are very successful in people with PKD. Kidney transplantation is the best way of regaining full health. Occasionally the kidneys by then are so big that one must be removed to make space for dialysis or for a kidney transplant. Removing a kidney this size is a big operation and is only done if it is essential.
Where can I get further information?
PCKD is quite a common disorder and a lot of other information is available. Several patient associations and charities run websites and provide written information. The following are particularly good:
- A booklet on PCKD from the St George's Hospital (London) Patients Group is very good indeed. It is available on-line from the Cambridge Polycystic Research group as a pdf file. The rest of the group's site is purely research-related and very complex
- The Polycystic Kidney Research Foundation provides a very good website. They also have written information, available from their headquarters at: 4901 Main Street, Suite 200, Kansas City, Missouri 64112-2634
Telephone: (+001)(816) 931-2600; Fax: (+001)(816) 931-8655; or by email, pkdcure@pkrfoundation.org - The UK-based PKD Charity provides support and useful information.
- The NKF (UK) have some quite good information on PCKD under Medical Info.
- PKD Access centre has some further information and links.
SMALL PRINT Our page on disorders that may be confused with PCKD is for doctors and others with renal expertise.
The following EdRenINFO sites contain relevant information:
Do you know other sources that should be included? Let us know
Up to top
| (no previous) | (no next) |
