Chronic Kidney Disease /Cats

Chronic kidney disease (CKD) – is the most prevalent disease you and your cat may face as they age. It typically affects up to 40% of cats over the age of 10 and 80% of cats over the age of 15. To begin with healthy kidneys are the filtering organs and perform many functions, including filtering the blood, making urine, and regulating blood pressure (BP). CKD refers to the persistent loss of kidney function over time and can have many health problems associated with it. It is important to monitor your cat as they age to watch for the development of CKD.

Clinical Signs (CS) – In the early stages of CKD, it is common that many cats will show no signs of disease as they are able to compensate for the decrease in kidney function. As the kidney function decreases (loses the ability to concentrate urine effectively) cats may begin to urinate greater volumes and drink more water to compensate. Loss of important proteins and vitamins in the urine may contribute to abnormal metabolism and loss of appetite (inappetence). Eventually, cats with CKD may develop a buildup of waste products in their bloodstream (BUN, Creatinine) that are normally removed by the kidneys; this buildup may make them feel lethargic, lose weight and appear unkempt.

Patients with CKD are also at risk of hypertension (elevated blood pressure) and anemia (low red blood cells) due to the role of the kidneys. Hypertension can lead to sudden changes in vision (including blindness), neurologic abnormalities such as weakness and disorientation, and/or heart issues. The kidneys also normally produce a hormone called erythropoietin; this is a vital aspect of red blood cell production. Patients with CKD produce less of this hormone which can lead to anemia, a lack of red blood cells (RBCs) can lead to lethargy, poor appetite, and pale/white gums.

Evaluation/Diagnosis

To evaluate kidney function, your veterinarian will most often run blood test (chemistry/complete blood count) and urinalysis to determine the health of your cat’s kidneys. Your veterinarian should also evaluate your cat’s blood pressure to determine if there is any hypertension at time of diagnosis to ensure proper CKD staging.

IRIS Guidelines: https://www.iris-kidney.com/

Treatment/Management

Unfortunately, CKD is a progressive disease, so the treatment goal is to slow progression and maintain a good quality of life (QOL). Therapy goals are to minimize toxic waste buildup in the bloodstream, maintain adequate hydration, support nutrition, control blood pressure, and address electrolyte disturbances.

Dietary modification – an important and proven aspect of treatment and typically the first recommended change. Studies suggest that therapeutic diets that are restricted in protein, phosphorus and sodium content and high in water-soluble vitamins, fiber, and antioxidant concentrations may prolong life and improve quality of life in cats with CKD. Some patients are very picky however about therapeutic diets, so owner compliance and gradual transition/finding the right diet for your cat is an important factor in diet management.

Maintaining good hydration status is essential as dehydration can speed up damage to the kidneys. At home this can be encouraged by feeding wet formulations of food and ensuring access to multiple clean water sources. Water fountains often encourage cats to drink due to cats’ curious nature and the flowing nature of the water. In some cases, administration of fluids under the skin (SQ fluids) may be necessary to help your cat stay hydrated; your veterinarian can help determine if this is necessary.

Cats with chronic kidney disease (CKD) may require various treatments to manage symptoms and slow disease progression. These include phosphate binders to reduce blood phosphorus levels, antibiotics for bladder infections, potassium supplementation to address muscle weakness, B vitamins for depleted water-soluble vitamins, anti-emetics to reduce vomiting, blood-pressure lowering drugs to manage high blood pressure, medication to reduce proteinuria, and treatment for anemia to stimulate red blood cell production.