23 Oct Chronic Kidney Disease in Cats – Causes and Diagnosis
Chronic kidney disease is a condition commonly seen in older cats and is a long-term degradation of the kidneys’ ability to function properly to filter and regulate electrolytes, toxins, and metabolites from the body. There are many causes of chronic kidney disease which are known, but also a lot which is unknown. Exposure to certain toxins, polycystic kidney disease, some kidney cancers, kidney infections (pyelonephritis), congenital kidney deformities and long-standing electrolyte disturbances are all examples of states which can increase the chance of renal failure in cats. Cats are much more prone to developing chronic kidney disease than dogs, so it’s something that as veterinarians we always have in the back of our minds when examining an unwell feline patient.
The initial diagnosis of chronic kidney disease is made by combining the physical examination findings and history of illness with both blood and urine tests. The blood and urine tests are useful in working out how well the kidneys are managing to filter out metabolites and regulate electrolytes within the body, and if the kidneys can adequately concentrate urine so that not too much water is being lost from the body. Once the initial diagnosis has been made, optimally the disease will be further staged so that we can have an idea of underlying causes and prognosis, and if any further medications are required. Staging is done in a few main steps;
- Abdominal ultrasound. The main use of this is to ensure that there isn’t something else going on that could be treated otherwise. Diseases such as kidney cancers, kidney infections, and congenital kidney problems can often start to be diagnosed with ultrasound, and this could drastically change the treatment required for your feline friend.
- Urine protein content. Part of the staging for kidney disease is working out if an excessive amount of protein is being lost through the urine (proteinuria). This allows the first part of substaging kidney disease to best direct treatment.
- Blood pressure monitoring. Chronic kidney disease can cause high blood pressure, which can cause what is known as “target organ damage” by restricting blood being able to flow to an organ appropriately. Measuring blood pressure can sometimes be tricky, but is important to direct appropriate treatment in unison with treating any proteinuria to ensure that other organ systems aren’t also suffering damage concurrently.
If you are concerned that your cat may have any form of kidney disease, then it is likely worth having them checked out by your local veterinarian. Oftentimes excessive drinking and urination are the first signs, but weight loss and general lethargy and malaise are also signs which could be indicators of kidney disease. If you notice any of these signs, it might be worth contacting your local vet clinic and having a discussion with your vet about your cat’s kidney disease treatment.