Don't Ignore Feline Kidney Disease Warnings: Frequent Urination and Increased Thirst!

Has your cat recently experienced symptoms such as frequent urination and thirst? They could be signs of kidney disease in cats. Statistics show that kidney failure is one of the leading causes of death in domestic cats. The symptoms may not be obvious at first, making it difficult for owners to detect until the disease has progressed to a later stage. This article will provide a detailed overview of the causes and symptoms of kidney disease in cats, helping owners to detect and effectively manage it early. Don't miss out on this article if you're a cat lover!

Causes of Kidney Disease in Cats

There are many high-risk factors that can cause kidney disease in cats, including hypertension, infections (such as Periodontitis), use of nephrotoxic drugs, inadequate water intake over a long period of time, genetics, and breed (such as Maine Coon, Abyssinian, Siamese, Russian Blue, etc.), and vaccination. The causes of kidney disease can be divided into three main categories: prerenal, intrinsic renal, and postrenal.
Prerenal causes: Reduced blood flow to the kidneys due to low blood pressure, heart disease, or other factors can impair kidney function and hinder waste metabolism.
Intrinsic renal causes: Acute kidney failure caused by damage to the kidney tissue itself, usually due to tumors, blood clots, or surgery.
Postrenal causes: Acute kidney failure caused by urinary tract obstruction, urethral blockage, or kidney obstruction

Clinical Symptoms of Kidney Disease in Cats

The clinical symptoms of feline kidney disease include increased water intake and urination, decreased activity level, frequent vomiting, weight loss, decreased appetite, and dehydration. If owners notice these symptoms in their cats, they should seek veterinary care promptly for diagnosis and treatment.
IRIS Staging of Feline Chronic Kidney Disease
Familiarity with the stages of chronic kidney disease in cats defined by the International Renal Interest Society (IRIS) can aid pet owners in accurately assessing the severity of their cat's kidney disease.

• Stage 1: Renal Insufficiency (Early Stage)

Cats typically need only 25% of their kidney function to efficiently eliminate toxins from their body. In the early stage, cats still have 33% to 99% of their kidney function, so symptoms may not be apparent and can easily go unnoticed by owners. Cats may display symptoms such as electrolyte imbalances, diluted urine (with a lighter color and odor), slightly increased urine volume, and proteinuria. Early detection of kidney problems in cats is crucial for protecting their kidney health.  To monitor the kidney health of cats in Stage 1 of kidney disease and detect any potential issues as early as possible, it is recommended that they undergo regular analysis of kidney-related indices (such as Creatinine and SDMA) during each follow-up visit with a veterinarian.

• Blood test values: Creatinine less than 1.6 mg/dL, SDMA less than18 μg/dL
• Common treatment approaches: Encourage increased water intake and feed them food with higher moisture content.

• Stage 2: Renal Insufficiency (Advanced Stage)

As a cat's kidney function drops between 25% to 33%, it has to put more effort to filter toxins from its body. This decrease in function also affects their ability to concentrate urine, causing symptoms such as increased frequency of urination and urine volume, leading to dehydration and increased thirst. Neglecting treatment of this condition may result in a quick worsening of the cat's condition, and can lead to complications such as proteinuria and hypertension. To ensure the well-being of the cat, owners should collaborate with their veterinarian, schedule frequent follow-up visits, and promote water consumption.

• Blood test values: Creatinine between 1.6-2.8 mg/dL, SDMA: 18-25 μg/dL
• Common treatment approaches: Renal therapeutic diet, medications to control symptoms

• Stage 3: Kidney Failure (Early Stage)

In stage 3 kidney failure, a cat's kidneys can no longer efficiently filter toxins from its body. This leads to dehydration and proteinuria, characterized by an excess of protein in the urine. Consequently, the cat may experience rapid weight loss (a decrease of 5% or more in body weight within a month, e.g., from 4 kg to 3.8 kg), poor appetite, and lethargy, which can be attributed to the loss of body fluids and proteins. Furthermore, hypertension may develop, further impairing the kidneys and exacerbating the condition. To manage this, cat owners should regularly schedule veterinary visits for treatment, monitor their cat's water intake, eating habits, and changes in body weight, and encourage them to drink more water.

• Blood test values: Creatinine: 2.8-5.0 mg/dL, SDMA: 26-38 μg/dL
• Common treatment approaches: Renal therapeutic diet, subcutaneous fluids, and medications to control symptoms such as high blood pressure and proteinuria.

• Stage 4: Kidney Failure (Advanced Stage)

When a cat reaches stage 4 of kidney disease, their kidney function drops to below 10%. This is a severe condition that can lead to a buildup of toxins in the cat's body, resulting in frequent vomiting and persistent dehydration. These symptoms can make the cat lethargic and cause them to lose their appetite. If left untreated, high blood pressure can lead to complications such as blindness, heart disease, and seizures.
The focus of treatment at this stage is on maintaining the cat's quality of life and managing its symptoms with appropriate medication. Unlike earlier stages, the emphasis is no longer on slowing down the progression of the disease. Owners should carefully consider whether to use appetite stimulants or feeding tubes to provide their cats with the necessary nutrition and medication to help them through this challenging period.

• Blood test values: Creatinine: >5.0 mg/dL, SDMA: >38 μg/dL
• Common treatment approaches: Encouraging increased water intake, renal therapeutic diet, subcutaneous fluids, symptom-specific medications, appetite stimulants, or feeding tubes as needed.

We hope that this article helps readers gain a better understanding of the causes and clinical symptoms of feline kidney disease, as well as the corresponding treatment for cats at different stages. In our next article, we will explore the topic of diet and care for renal cats, and work together to promote their health and well-being!