Kidney Disease in Dogs and Cats > Causes of Kidney Failure
Kidney failure, also referred to as renal failure or sometimes renal insufficiency, can occur in both dogs and cats.
In a healthy dog, the kidneys filter waste products that are produced by the body. In kidney failure, these waste products are not filtered properly and start to build up in the blood stream. This is called uremia or azotemia.
Types of Kidney Failure in Dogs and Cats
Kidney failure can be acute or chronic. When kidney failure happens suddenly, it is referred to as acute kidney failure. If your dog or cat has had symptoms for several months or longer, it is called chronic kidney failure.
Canine and feline kidney failure can also be classified as pre-renal, renal or post-renal.
- Pre-renal kidney disease occurs when the blood supply to the kidneys is decreased. In this situation, the initiating disease is not located in the kidneys. However, the kidneys can become damaged if their blood supply remains insufficient. Potential causes of pre-renal disease include dehydration, shock, heart disease and low blood pressure.
- Renal disease can also when there is damage directly to the kidneys.
- Post-renal kidney disease occurs when the cause of the kidney damage is a result of disease located in the ureter (the tube that runs from the kidney to the bladder), the bladder or the urethra (the part of the urinary tract that runs from the bladder to the outside of the body.) The most common example of post-renal kidney failure is urethral obstruction. This occurs when a bladder stone or other object blocks the urethra and the pet becomes unable to pass urine. The urine accumulates in the bladder and eventually causes kidney failure. (This is a life-threatening issue that can cause death very quickly.)
Causes of Canine and Feline Kidney Failure
There are many causes of kidney failure. Some of the more common ones are:
- bacterial infections, such as leptospirosis and Lyme disease in dogs
- viral diseases, such as feline infectious peritonitis (FIP) in cats
- immune-mediated disorders, such as systemic lupus
- inadequate blood flow to kidneys, which may result from shock or trauma
- toxins, including grapes and raisins, antifreeze, lilies (cats) and certain drugs
- congenital diseases, such as polycyctic kidney disease
- metabolic diseases, like hyperparathyroidism (disease of the parathyroid gland) or vitamin D toxicity
- cancer, which can be primary (starting in the kidneys) or metastatic (spreading from other parts of the body)
- degenerative changes, including aging changes
In many cases, the initiating cause of kidney failure in the dog or cat is never actually identified.
More: Kidney Disease in Dogs and Cats - Signs, Treatment, Diagnosis
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