Chronic Kidney Disease (CKD) is defined as the presence of structural or functional abnormalities in one or both kidneys that persist for an extended period, typically three months or longer. This definition highlights that CKD encompasses a wide spectrum of disease, ranging from minor structural lesions in a single kidney to extensive loss of nephrons affecting both kidneys.

The International Renal Interest Society (IRIS) recognizes that early stages of CKD may not always present as azotemia, emphasizing the importance of identifying other markers of kidney damage. Regardless of the underlying cause, CKD is generally considered a progressive disease , with tubulointerstitial inflammation and fibrosis being common pathological findings. These processes involve the buildup of scar tissue within your cat's kidney, impairing its ability to function effectively.

Recognizing the markers of kidney damage is an essential step in the early detection and management of CKD in your cat. These markers can be identified through blood and urine tests, as well as imaging studies.

Elevated levels of blood urea nitrogen and serum creatinine are common indicators of impaired kidney function in your cat. Other blood markers include hyperphosphatemia, hyperkalemia or hypokalemia, metabolic acidosis, and hypoalbuminemia.

Impaired urine concentrating ability is a significant sign, along with proteinuria (presence of protein in the urine), cylindruria (presence of urinary casts), renal hematuria (blood in the urine), inappropriate urine pH levels, and inappropriate glucosuria (glucose in the urine).

Abnormalities detected through imaging, such as changes in kidney size, density, shape, number, location, and mineralization, can provide valuable insights into the structural health of your cat's kidneys.

It is crucial to confirm that these markers are of renal origin to accurately diagnose CKD. For example, hypoalbuminemia (low albumin levels) due to urinary protein loss indicates kidney disease, whereas hypoalbuminemia due to hepatic failure does not.

Feline CKD is a multifactorial disease, influenced by a combination of genetic, individual, and environmental factors. Understanding these risk factors is essential for implementing preventive strategies and ensuring early detection in your cat.

Diet plays a crucial role in the development and progression of CKD in your cat.

• Renal Diets: these diets are specifically formulated to support your cat's kidney health, with modifications such as reduced protein, phosphorus, and sodium content. They also include increased B-vitamin and soluble fiber content, increased caloric density, a neutral effect on acid-base balance, supplementation of omega-3 polyunsaturated fatty acids, and the addition of antioxidants. Feline renal diets are often supplemented with potassium to address potential deficiencies in your cat.

• Water Source: the source of drinking water can also impact your cat's kidney health. Tap water was identified as a risk factor for CKD, while filtered water was associated with a decreased risk .

• Urine-Acidifying Food: studies have found that cats with CKD and upper urolithiasis were more likely to be fed urine-acidifying food only.

Lifestyle and environmental factors significantly influence the risk of CKD in your cat.

Cats with an outdoor lifestyle were found to have a higher risk of developing CKD . This increased risk may be attributed to exposure to toxins, infectious diseases, and traumatic injuries. Conversely, an indoor lifestyle was associated with a decreased risk, providing your cat with a more controlled and safer environment.

Several concurrent health conditions can elevate the risk of CKD in your cat.

• Poor body condition, periodontal disease, and cystitis have been identified as potential contributing factors to kidney disease in cats.

• Urolithiasis: Upper urolithiasis, the presence of stones in the upper urinary tract, is relatively common in cats with CKD. Purebred cats and cats fed dry food only are more likely to develop upper urolithiasis.

Regular veterinary check-ups are essential for the early detection and management of CKD in your cat. Because CKD tends to be progressive, your cat's needs may change with time.

Cats in CKD stages 3 and 4 should be evaluated every 3 to 4 months. Cats in CKD stages 1and 2 often require less frequent monitoring, approximately every 4 to 6 months, once stable renal function has been established. However, if your cat has progressive CKD, proteinuria, or arterial hypertension, they should be monitored more frequently.

A typical monitoring visit for your cat should include a thorough medical history, physical examination, body weight and nutritional assessment, hematocrit, chemistry profile, urinalysis, and blood pressure measurement. Depending on your cat and the results of the urinalysis, a urine protein/creatinine ratio and urine culture may also be included.

Dietary management is a cornerstone of CKD treatment for your cat. The goals of a renal diet are to reduce the workload on your cat's kidneys, manage electrolyte imbalances, and minimize the accumulation of toxins.

It is important to avoid substituting maintenance or senior diets for renal diets, as these alternatives may not provide the specific nutritional support required for your cat with CKD. Feline renal diets are often supplemented with potassium to address potential deficiencies in your cat's system.

Metabolic acidosis, a condition characterized by an excess of acid in your cat's body, can promote the progression of CKD and impair protein nutrition. Alkalinization therapy is indicated for your cat with CKD stages 1 to 4 when blood pH levels and bicarbonate concentrations drop below the normal range.

Changing to a renal diet may improve acidosis by providing a pH-neutral diet for your cat. When diet alone is insufficient, administration of an alkalinizing salt, usually sodium bicarbonate or potassium citrate, is indicated.

Understanding and mitigating the risk factors associated with Chronic Kidney Disease is of paramount significance in safeguarding the long-term health and well-being of your feline companion. By recognizing the influence of dietary choices, lifestyle factors, breed predispositions, and concurrent health conditions, you can take proactive measures to protect your cat's kidneys.

Regular veterinary check-ups are crucial for early detection and monitoring , enabling timely interventions to slow the progression of the disease and enhance your cat's quality of life.

It is essential to consult with your veterinarian for tailored advice and monitoring, ensuring that your cat receives individualized care based on their specific needs and risk factors. As a dedicated cat owner, embracing proactive care and informed decision-making empowers you to provide the best possible support for your beloved feline friend, ensuring they lead a healthier, happier life.