If your kitty has mouth ulcers, is vomiting a lot, seems to be losing weight, or appears especially weak, she may be dealing with feline kidney failure. This very serious condition can be chronic or acute, and it always requires a trip to the vet. Find out how to spot the symptoms and get your cat some help.
Feline Kidney Failure - Chronic or Acute
Feline kidney failure may either be chronic or acute. Chronic Renal Failure (CRF), also known as Chronic Renal Insufficiency (CRI) is progressive and irreversible. Although there is no cure, the condition is managed with a special diet, drugs, and fluid therapy. Acute Renal Failure (ARF) is sudden onset kidney failure, often the result of CRF in its crisis stage having not being addressed appropriately at early onset, or may also be caused by urinary obstructions, infectious diseases, trauma, or toxins ingested by the cat such as antifreeze (which contains ethylene glycol). Characterized by an abrupt shutdown of the kidney function, ARF is extremely serious and is often fatal. However, depending upon the severity of the damage, with prompt and aggressive medical attention, it may be possible to restore normal kidney function.
How the Kidneys Work
Kidneys are a complex pair of organs made up of approximately 200,000 tiny structures called nephrons. When the nephrons die off, waste products and electrolytes are no longer processed effectively resulting in CRF.
Kidneys have five primary functions:
- Filter and eliminate waste products from the body
- Regulate electrolytes such as potassium, calcium, phosphorus, and sodium
- Production of erythropoietin which helps to stimulate bone marrow and produce red blood cells
- Production of rennin, the enzyme that controls blood pressure
- Production and concentration of urine
Symptoms and Behaviors of CRF
The two most telling preliminary symptoms of feline kidney failure are increased thirst (polydipsia) and excessive urination (polyuria). If you observe either of these symptoms, you should have your cat clinically tested as soon as possible for an accurate diagnosis. It is imperative to begin treatment before the condition progresses. Only 30 percent of kidney capacity is required for normal functioning, therefore by the time your cat is exhibiting the first signs of kidney failure, already 70 percent of the renal function has been lost.
Unfortunately, even with dietary control, medications, and fluid therapy, cats will exhibit some or all of the following symptoms and behaviors at some point in the progression of the condition:
- Weight loss
- Poor hair coat
- Nausea
- Gagging
- Licking of lips
- Grinding or cracking sound in the jaw
- Vomiting (clear or foamy liquid and food)
- Hunching over their water bowl
- Dehydration
- Emaciation
- Drooling
- Stomach irritation
- Halitosis (odor of ammonia)
- Sound sensitivity
- Lethargy
- Weakness
- Muscle atrophy
- Ulcers in the mouth
- Eating litter
- Depression
- Detached retinae
- Uremic gastritis (stomach irritation)
- Constipation
In the final stages of renal failure, convulsions and coma are common.
Causes of CRF
Although there may be several causes for CRF, the common contributing factors are age, genetics, environment, and disease. Studies have also proven a strong link between CRF and low potassium levels, high acid content in the diet, and dental disease.
Renal disease is usually generally diagnosed as CRF in the vet's office, with the cause most often not known. However, CRF is divided into two groups and may be congenital or acquired.
Age Related CRF
CRF is one of the leading causes of illness and death in older cats. Have your vet check your seven years or older cat annually for signs of CRF. Blood tests, urinalysis, and blood pressure measurement provide early detection. If CRF is diagnosed before significant deterioration, proper diet and hydration therapy will allow your cat to remain happy and active for some time before its health inevitably declines. Your ability to observe the symptoms and behaviors associated with renal failure and to act quickly, is key to your cat's health and quality of life.
Congenital Kidney Disease
Congenital kidney disease (PKD) is inherited. The breeds which tend to have a higher rate of CRF than others are Maine Coon, Siamese, Burmese, Balinese, Abyssinian, and Russian Blue. Congenital renal disease may begin in kittens and younger cats of certain breeds and include the following:
- Polycystic Kidney Disease (PKD) is most common in Persians and Persian crosses between Domestic Short Hairs and Persians and is manifested by cysts developing in the renal medulla and cortex resulting in kidney failure.
- Renal Aplasia is a birth defect which occurs when one or both kidneys are not present
- Renal Dysplasia occurs when one or both kidneys develop abnormally
- Renal Hypoplasia occurs when one or both kidneys have a reduced number of nephrons which work properly
Acquired Kidney Disease
Acquired kidney diseases are caused by obstructions, inflammatory diseases, infections, and unknown causes, and include the following:
- Chronic Interstitial Nephritis is the most common cause of CRF in cats and is often the end result of other kidney diseases. The kidneys become shrunken and the normal kidney tissue becomes dead scar tissue.
- Familial Amyloidosis is common in Abyssinian cats with unknown cause. Amyloidosis occurs when a protein substance called amyloid, is deposited in the kidneys.
- Glomerulonephritis is an inflammatory disease
- Hydroephrosis is caused by an obstruction which prevents normal urination
- Pyelonephritis is a bacterial infection of the kidneys
- Renomegaly is the enlargement of one or both kidneys
Prevention of Kidney Disease
We all want our feline companions to live a long happy life. Regular annual visits to your veterinarian are an essential component in the prevention of many diseases and conditions, including CRF. In addition to blood tests, potassium level monitoring, and urinalysis, your cat's check-up should include a thorough examination of the mouth, teeth, and gums. There is a proven connection between dental problems and CRF and keeping the teeth clean and tartar-free goes a long way to keeping a cat healthy. In fact, CRF is often diagnosed after routine teeth cleaning or dental surgery.While it is the most common disease in cats, not all cats will get CRF. For those cats diagnosed with this terminal disease, it is still possible for them to enjoy a relatively good quality of life for several months or even years with early detection and proper treatment therapies.
