Polycystic Disease in Cats

Polycystic kidney disease, or PKD, is an inherited disease that results in the appearance of fluid filled cysts on one or both kidneys of a cat. These cysts are present at birth and grow as the cat ages. As these cysts grow, they can damage kidney tissue and prevent proper function. If left untreated, the cysts will eventually cause kidney failure in the cat as the organs will no longer be able to perform adequately to keep the body healthy.

  1. Risk Factors

    • PKD is an inherited, genetic disease that afflicts primarily Persian breed cats although British Shorthairs, Himalayans and other exotic breeds have been documented as having the condition. Cats can inherit the PKD gene from one or both parents. A heterozygous cat has one PKD gene, while a homozygous cat has two. Heterozygous cats can pass the gene on to 50 to 75 percent of their offspring, while 100 percent of the offspring from homozygous cats receive it.

    Symptoms

    • Symptoms of PKD may not be apparent for years, depending upon the number of cysts and their size. According to the Pet Education website, signs generally appear between 3 and 10 years of age, and most cats begin showing symptoms at 7 years old. Common symptoms of PKD include weight loss, vomiting and depression. Enlarged kidneys are also common. And the cat may also exhibit an increase in thirst and urination.

    Diagnosis

    • PKD can be confirmed by using a combination of methods, including ultrasound, physical examination and genetic testing. Pet Education's website reports that kittens as young as 10 months old can be diagnosed with PKD by performing an ultrasound to look for cysts on the kidneys. Your veterinarian may also be able to feel enlarged or misshapen kidneys through palpation. A swab taken from the inside of the cat's cheek can be tested for the PKD gene for unquestionable diagnosis.

    Treatment

    • PKD is progressive and irreversible. The cysts cannot be removed surgically due to their number and small size. Treatment ultimately entails dealing with the eventual failure of the kidneys because of the disease. Fluids may be given by IV or subcutaneously to prevent dehydration, and your cat's diet may be changed to provide foods higher in potassium and lower in phosphorous. Medications may be prescribed to control vomiting and high blood pressure and slow the progression of renal failure.

    Prevention/Solution

    • Because PKD is a genetic disease, the only way to prevent the development of it is to not breed the cats who carry the gene. Cat breeders of the susceptible breeds should take care to breed only those cats that are determined to be PKD negative through ultrasound study of the animal's kidneys. PKD positive cats should be spayed or neutered to stop the genetic trail of the disease.