Chronic kidney disease in cats

Chronic kidney disease (CKD) in cats is a condition that involves long-term damage to the kidneys. Although this may not cause significant disease at first, it’s often progressive to the point where there’s a loss of normal kidney function leading to water loss through the kidneys into the urine causing dehydration. There’s also a build up of waste products that the kidneys can’t filter out anymore that cause nausea, inappetance and sometimes even vomiting.

Kidney damage is usually irreversible and frequently progressive, with clinical signs usually only being seen when over two-thirds to three-quarters of kidney function has been lost.

The underlying causes of CKD are often unknown. Cats are particularly susceptible – and in many cases it’s thought that multiple spells of a kidney not working may cause progressive kidney damage over time. However, by the time CKD is diagnosed the initial cause(s) of the damage may have long since disappeared, with the kidneys only showing thickening and scarring from previous problems. 

Your vet will usually rely on a combination of blood and urine tests to make a diagnosis of CKD. Blood tests can detect elevations of compounds normally excreted by the kidneys and analysing the urine at the same time may show an abnormally low concentration.

CKD may sometimes be diagnosed incidentally on a routine visit, but it’s most often diagnosed in later stages where signs of disease have already been noticed.

Once diagnosed, other tests will normally be recommended including measuring blood pressure, looking at protein concentrations in the urine, and perhaps diagnostic imaging (ultrasound or X-rays to look at the kidneys). Tests for infectious diseases and toxins may also be carried out to discover if there is a potential cause.

CKD is usually both irreversible and progressive. Unless a specific underlying treatable cause is identified (such as a bacterial infection of the kidneys), the main strategy is to support kidney function, reduce any further kidney damage , and manage any complications associated with the condition.

High blood pressure causes excessive protein loss from the kidneys which in turn has been associated with more rapid progression of kidney disease. Medication to alleviate the signs of high blood pressure reduces the amount of protein being lost by the kidneys which is associated with improved survival rates in cats.

Managing CKD usually requires regular assessments of blood pressure, repeat blood tests, and analysis of urine samples so that the consequences and complications of CKD can be detected early, and treated effectively.

Find out more on CKD by visiting our friends at Cat Professionals