Why are our cats PKD negative tested by DNA-Test?




Polycystic kidney disease?? Autosomal Polycystic Kidney

Disease (PKD) is a progressive, inherited condition which

causes multiple fluid filled cysts on the kidneys of

Persians/Exotic cats and also of breeds with Persians/

Exotics in their lines.


In fact the Cysts are present from birth, but are

tiny at the beginning and will slowly increase the size.

They can range from very small up to several centimetres

in diameter. When the Cysts start increasing their size

they damage the normal kidney tissue, which causes

eventually kidney failure.


The number of cysts, the speed & the size in which

they grow varies from cat to cat. The average age of

kidney failure due to PKD is around 7 years. Some cats

will day very young while others will get very old and

die because of something different than PKD.



How is PKD inherited?


Genetic studies approved that PKD is autosomal

dominant. So if only one parent has this gene he/she

will pass it on to the offspring with a chance of 50% of

inheriting PKD. Cats that are genetically free of PKD

have no possibility to pass it to the kittens.



What are the signs of PKD?


Weight loss






Polyuria (excessive urination)


Polydipsia (excessive thirst)




Enlarged kidneys



How is PKD diagnosed?


Ultrasound: When the cat has reached approx.

10 month of age the Ultrasound diagnosis is 98% accurate.

The Ultrasound should be performed by a vet. that is

skilled to use the ultrasound.


Genetic Test: A buccal swab (from inside the cheeks)

will be send to a specialised laboratory for testing.

The result of this test is 100% accurate.





Unfortunately there is nothing that you can do

to slow down the growth of the cysts and they can't be

removed. When kidneys begin not to work properly, they

lose their ability to filter out toxins. To understand

the treatment please find below a brief summary of how

the kidney's work:


Kidneys are releasing an enzyme called

Renin to help control the blood pressure. When blood

pressure drops and kidneys don't receive enough blood,

Renin is released and will be causing blood vessels to

contract. When blood vessels contract, the blood pressure

goes up again. The main function of Kidneys is to filter

waste products and excess water from the blood. Wast

products leave the body in urine and the cleanded blood

remains in the body. The Stimulation of red blood cell



They help maintain the proper balance of acid and minerals,

including sodium, calcium, potassium and magnesium, in the



So it is very important helping to reduce the level

of toxins in the cat. This Treatment is based on aa cat

with chronic renal failure & may include:


Administration of fluids subcutaneously to treat dehydration.


Prescription diet: This food contains a lower

percentage of protein and less phosphorus than normal cat

food. For the growth, building muscles and repairing tissue

cats need protein every day. After the body uses the

protein in the food, a waste product called urea is made.

If a cat has a kidney failure it is not able to get rid

of this urea on a normal way. Damaged kidneys may not be

able to remove phosphorus from the blood so the level of

phosphorus in the blood will become too high. With a high

blood phosphorus level the cat might lose calcium from

their bones.


Phosphorus binders can be given (available in tablet or

capsule form).


High blood pressure (hypertension): If the blood

pressure is too high Medication may be prescribed.


Antacids & anti nausea medication.


Erythropoeitine: The kidneys produce a hormone,

erythropoietin, which instructs the bone marrow to produce

red blood cells. The red blood cell count is often low

by cats with kidney failure. Since only the human form

is available there is a possibility that some cats may

eventually recognise this substance as foreign and build

antibodies against it.



What is the outcome for a cat with PKD?


It is so different from cat to cat. It's depending

on how many cysts are present, how large they grow and

how quickly they grow. A cat with only a few small & slow

growing cysts may live very long and will die eventually

from something unrelated to PKD. Other cats may die very

young if they have numerous cysts that are growing and

become large very fast.



Is there a cure?


Unfortunately there isn't a cure for PKD. Breeders

should test their cats and if one of the cats should be

PKD positive tested, it should be desexed.


Note: Some breeders are using PKD positve cats in

their breeding programs because some lines are too

precious to lose. Especially if somebody is breeding rar

colors like chocolate and lilac, he has to go sometimes

the more difficult and longer way to be successfull.

Of course they will go on breeding with the kittens that

are PKD negative out of this combination and the rest will

be neutered/spayed.


If you are interested in a kitten from a breeder that

is breeding with NOT PKD negative cats please ask the

breeder directly why he/she is working with PKD positive

cats. Remember that PKD positive doesn't mean that the

cat will die of PKD.







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