You should seek the advice of your veterinarian if your pet is ill as only he or she can correctly advise on the diagnosis and recommend the treatment that is most appropriate for your pet.

Multiple cyst formation in the kidneys of Persian cats is a well established disorder

Cyst formation within kidneys is not an uncommon finding in cats and dogs. Multiple renal cysts (polycystic kidney disease) in Persian and Persian-related cats is an inherited disease transmitted through an autosomal dominant gene, so only one parent needs to be carrying the trait for the offspring to be affected. In the USA approximately 37% of Persian cats have this disorder when screened (see below). Occasionally cysts are also found in other tissues such as the liver or uterus of affected cats, and a few cats that produce affected offspring only have single cysts, or only one kidney is affected. This disorder has also been reported to occur in domestic long haired cats.

The cysts are usually present in both kidneys from birth and they grow gradually, eventually becoming over 1 cm in size, causing the kidneys to enlarge and damaging kidney tissues, resulting in kidney failure. The clinical signs of kidney failure and kidney enlargement usually become evident during middle-age at about 6-7 years of age. 

Signs of polycystic kidney disease include :

• Inappetance
• Depression
• Increased urine production (polyuria)
• Increased thirst (polydipsia)
• Weight loss
• Abdominal distension (in older cats)

Diagnosis can be confirmed by various imaging techniques - especially ultrasound, and the disorder can be detected as early as 4 weeks of age using this technique. Screening Persian cats at 10 months of age results in 95% of cases being detected. If a cat is found to be positive other relations should be checked, and breeding should not be allowed from affected individuals.

There is no specific treatment for polycystic kidney disease other than treatment for renal failure. The prognosis is poor, but the disease affects individuals at different rates and not all cats will progress through to kidney failure and death.

Updated October 2013