feline chronic kidney disease
Chronic kidney disease (CKD) is diagnosed frequently in our feline patients, especially those in their senior years. In fact, studies have estimated more than 30-40% of cats over the age of 10 are affected by the condition.
What causes CKD?
There are many theories about the underlying cause of CKD in cats, however in most cases the cause remains unknown. Long term studies into CKD show chronic inflammatory changes throughout the kidneys, but unfortunately it is difficult to know what started the inflammatory process. There are some cases of CKD which have a known cause, and these specific cases can normally be diagnosed with imaging and sometimes biopsies. Unfortunately, in the majority of CKD cases we are unable to identify the original cause, however this does not change our management of the condition.
What are the signs of CKD?
Clinical signs associated with feline CKD include:
excessive thirst and/or urination
poor coat quality
urinary tract infections
high blood pressure
Unfortunately, many of these clinical signs only become evident as the condition becomes more advanced. This is because the kidneys have a huge ‘reserve’ capacity, and are still able perform effectively up until only a third of functional tissue remains. By this point we are unable to regain the loss of any damaged kidney, and so treatment and management focuses on supporting the remaining functional tissue.
How do we diagnose CKD?
There are many steps to both diagnose and stage CKD in cats. Initial tests include blood and urine sampling. Elevated levels of particular waste products in the blood, combined with a failure to concentrate urine are indicative of CKD. We can then further stage the disease process by testing blood pressure, looking for protein in the urine and by imaging the kidneys themselves using x-ray and ultrasound.
Management of CKD
CKD is a progressive condition of which unfortunately there is no cure. Despite this, cats can be managed very successfully with the condition, leading to an extended period of good quality life. They key to a better prognosis is early diagnosis, prompt intervention and frequent monitoring. The following are all elements of CKD management:
Diet: This is the first and most effective change we can make for any CKD patient. Prescription diets are designed specifically for the needs of our patients, and there is good evidence supporting renal diets in the management of CKD. Notably the diets are restricted in protein and phosphorous, however they are balanced with many other important vitamins, minerals, electrolytes and calories. There are various brands available on the market now, in a variety of flavours in consistencies.
Hydration: Our CKD patients are predisposed to dehydration, and dehydration itself can advance the progression of the disease. There are lots of tips to encourage water intake at home, including fountains, flavoured water, wet food and the use of different water bowls. For some patients in the more advanced stages of CKD, there is the option of giving fluids underneath the skin at home, or directly into a feeding tube.
Medication: There is medication available to treat conditions that develop secondary to CKD such as nausea, inappetence, high blood pressure, low potassium and excessive phosphate in the blood. It is important we manage these conditions, as left untreated they can accelerate the advancement of CKD.
Review: It is important that cats with CKD have frequent check ups, often every 3-6 months however you will be guided by your vet.
CKD is common in cats, especially over the age of 10. Early recognition and management can significantly improve and extend quality of life, and many cats cope extremely well with CKD. The current advice and recommendation is for any cat over the age of 7 years old to have health checks every 6 months to evaluate weight, body condition score and blood pressure. If there is any cause for concern, further sampling will be recommended.