Renal Disease

What is a renal failure?

Kitty and dog Renal failure, also known as kidney failure, is the inability for the kidneys to function properly. This happens when there is an accumulation of nitrogenous wastes and alteration in water, electrolyte, and acid-base status due to reduced functional renal mass.

Kidney failure can be described as chronic, meaning that the kidneys can no longer perform their crucial functions. The functions of the kidneys decrease slowly over time, which would present as gradual changes in your pet. However, there is also acute kidney failure, which presents as a sudden decline in kidney function. The physical signs of this in your pet can seem more dramatic since the decline is more rapid.

What are the physical signs of chronic renal failure?

  • Weight loss
  • Excessive drinking
  • Excessive urinating
  • Poor coat and decreased grooming
  • Lethargy
  • Vomiting
  • Bad breath
  • Lack of coordination
  • Depression
  • Wasting of muscle tissue
  • Not eating for a day or more
  • Weakness

If your pet is showing any of these symptoms, it is important to bring them to your veterinarian for an examination. During a physical exam, your veterinarian will look for specific markers including small kidney size, oral ulcers, dehydration, and poor body condition or poor coat.

How do you diagnose chronic renal disease (CRD)?

It is necessary to run full blood work to diagnose kidney disease. Typically, there is an elevation in the blood urea nitrogen (BUN) and creatinine. Other changes that may be seen on a blood panel could include electrolyte abnormalities and anemia. There are four stages of CRD, which are based on the elevated creatinine level in the blood as well as a decreased urine concentration.

Which other diagnostic tests are necessary?

It is not unusual to see cats diagnosed with CRD to have a high blood pressure as well. If your cat is diagnosed with CRD, a blood pressure should be taken and periodically checked every 3-6 months by your veterinarian.

A urinalysis is also key in the diagnosis of CRD and should be accompanied by the initial blood testing. The detection of protein in the urine is an indication that the kidneys are losing protein, which can further exacerbate the kidney disease. A urine protein/creatinine ratio may be needed to further quantify how much protein is being lost. Based on those results, medication may need to be prescribed to help prevent and delay further loss of protein. Urinary tract infections are also common in cats with CRD, which is also screened for when analyzing the urine.

How is renal disease treated?

Unfortunately, there is no cure for CRD. With the help and guidance of your veterinarian, it is a disease that can be managed. With certain treatments, the progression of the disease can be delayed.

Protein Restriction

If your cat is diagnosed with renal disease, your veterinarian will typically recommend a change in diet to a low protein diet. This special diet is necessary to decrease the amount of protein that the kidneys need to process.

Phosphorus Restriction

In a healthy pet, phosphorus is typically filtered out by the kidneys. In the case of CRD, however, the phosphorus level may increase in the blood, causing nausea, inappetence, and occasional vomiting. It is pertinent to keep the phosphorus level in the blood at a low level to help prevent these symptoms. The prescription renal diets that you can purchase from your veterinarian are reduced in phosphorus to help keep those symptoms at bay. In certain circumstances, a phosphate binder is also necessary to decrease the absorption of the phosphorus from the GI tract.

Potassium Supplementation

In advanced renal failure, sodium and potassium levels in the body are also affected. In these advanced cases, a potassium supplement is necessary.

Red Blood Cell Production

The kidneys are responsible for secreting erythropoietin, which stimulates red blood cell (RBC) production. In advanced renal disease, a decrease in kidney function also decreases the secretion of erythropoietin, which then leads to chronic anemia. Epogen is a substance that may be recommended by your veterinarian to help stimulate RBC production.

Hypertension Control

If your pet has high blood pressure it can further exacerbate their chronic renal disease and can potentially cause blindness from retinal detachment. Medication may be prescribed as needed to control hypertension.

Fluid Therapy

Cats with CRD can easily become dehydrated. It is sometimes necessary to administer subcutaneous fluids at home in order to maintain proper hydration. It is imperative that your cat drinks water regularly and is eating routinely.

If you are concerned that your pet is exhibiting any signs or symptoms of kidney disease, please schedule an appointment with your veterinarian immediately. The information provided here is for educational purposes only. Any treatment plan for your pet should be made on an individual basis between you and your veterinarian.