Polycystic Kidney Disease (PKD) is a hereditary kidney disease, which is mainly found in Persians and Exotic Shorthaired Pers, but also occurs in other breeds where Persians have been crossbred in the past.
PKD is most easily diagnosed by ultrasound examination of the kidneys, with which the disease can be detected from the age of ten months if cysts are found in the kidneys. For an examination, it is only necessary to shave the hairs over the middle of the belly and a short period (a few minutes) of scanning to determine the presence of cysts. Rarely is an anesthetic necessary. It is crucial that the scan is performed with the proper equipment and that radiologically trained veterinarians interpret the results. If all this is the case, the diagnosis is 98% certain.
PKD is a slowly progressing disease with an ultimately always-fatal outcome. The cat only becomes ill quite late in life, although cysts have been present for a longer time. Problems start with about seven years or so with enlargement of the kidneys and disturbed kidney function.
It has been proven that the disease is hereditary. Cysts are present from birth. The size varies from less than a millimeter to several centimeters. Older animals have larger and more cysts. The problems that cause the cat to get sick start when the cysts start to grow, and because of this, the functional kidney tissue is suppressed. As a result, the kidneys can no longer function properly. The cat eventually dies from the consequences of chronic kidney failure.
Clinical characteristics include:
- lethargy
- emaciate
- lack of appetite
- lots of extra drinking
- extra urination
The difference in the clinical picture between individual animals is significant. It differs from animal to animal in how quickly they become ill and how long it takes for them to die from the disease. It is also possible that an animal dies of another illness at an earlier age before the disease process of PKD dramatically reduces kidney function. What is certain is that a cat that has cysts will always get sick and get problems that eventually lead to death.
Since PKD is the result of 1 autosomal dominant gene, it is quite easy to trace that gene and remove it from a breeding stock in 1 generation. All breeding animals must be scanned to determine the presence of cysts. The quickest way to eliminate the problem is to castrate/sterilize all affected animals and only by breeding with PKD negative animals. A PKD-free cat is always genetically PKD-free and can, therefore, no longer pass on the disease to offspring.