Polycystic Kidney Disease (PKD)...
Persian cats are one of the breeds known to suffer from PKD (polycystic kidney disease). PKD is an inherited disease primarily found in Persian cats, related breeds, & cats with Persian ancestry. Other forms of PKD occur in other animals and in humans. PKD was occasionally reported in scientific literature as early as 1967, but actual study into this disease did not begin until 1990. In 2004, the mutation responsible for PKD in Persians and cats with Persian ancestry was identified.
When a cat has PKD, multiple cysts develop in both kidneys, sometimes leading to chronic kidney insufficiency or failure. Problems occur when these cysts start to grow and progressively enlarge the kidney, reducing the kidney's ability to function properly. Some of the signs of kidney insufficiency are increased thirst, increased urination, decreased appetite, weight loss, vomiting, and lethargy. Cats affected by kidney insufficiency due to PKD are usually identified when they are between three and ten years of age. PKD can be diagnosed by ultrasound of the kidneys, however, this test is only as good as the day it is done, cysts can develop later. Therefore, the ONLY reliable test for PKD is a DNA test Persian cats and cats with Persian ancestry.
In 2004, the University of California Davis developed a DNA test for feline PKD.
What is the likely outcome for a cat with PKD?
It really varies from cat to cat. How many cysts are present, how large they grow & how quickly they grow. A cat with only a few small & slow growing cysts may live to an old age & eventually die from something unrelated to PKD. Other cats may have numerous, large & quick growing cysts & die at an early age.
Is there a cure?
No, there isn't a cure for PKD. Breeders are advised to test their cats & if they are found to have PKD have them spay/neutered.
Some breeders continue to use PKD positive cats in their breeding programs. These breeders personally feel some lines are just too precious to lose. I personally feel that any cat that tests positive for PKD should be spay/neutered immediately and not be bred in order to prevent this horrible genetic disease from being passed on to offspring. So, if you see a cattery that is NOT PKD negative and you are interested in a kitten from that cattery, I would reconsider purchasing from this breeder. This is simply my personal opinion.