Chronic Renal Failure (Feline)
Feline Lower Urinary Tract Disease (FLUTD)
Leptospirosis

What do my cat's kidneys do?

The kidneys have many functions. They principally act to remove waste products from the blood stream, retain essential nutrients such potassium at the correct level, maintain hydration and produce urine.

What is chronic renal failure?

The kidneys have a large amount of spare capacity to perform their various functions so at least 70% of the kidneys need to be dysfunctional before clinical signs are seen. In many cases this means that the damage to the kidneys has been occurring over a number of months or years (chronic) before failure is evident. Chronic renal failure (CRF) is most commonly seen in older cats (10% of cases occur in cats less than 3 years old). Early signs of disease such as weight loss and poor coat quality are often dismissed as normal aging changes. In the initial stages of kidney disease, the kidneys cope with their inability to concentrate waste products by excreting them at a lower concentration over a larger volume. This is known as compensated renal failure. After approximately 70% of the kidney tissues are destroyed, there is a rapid rise in waste products in the bloodstream and an apparent sudden onset of severe disease.

What are the causes of CRF?

A large number of different disease processes can eventually lead to CRF including:

1.       Congenital malformations of the kidneys - e.g. polycystic kidneys in long haired cats

2.       Bacterial kidney infections (pyelonephritis)

3.       Glomerulonephritis - damage to the filtration membrane

4.       Neoplasia - various tumors of the kidney, most commonly lymphosarcoma

5.       Amyloidosis - this is the build-up of an unusual protein in the kidney that prevents the kidney from functioning normally

6.       Viral infections such as feline leukemia virus or feline infectious peritonitis virus.

CRF is the end stage of a number of different disease processes rather than a specific condition in its own right.

How is the disease diagnosed?

Renal failure is usually diagnosed by looking at the level of two waste products in the bloodstream, blood urea nitrogen (BUN) and creatinine and the urine specific gravity (USpG). Tests to measure the blood levels of other substances e.g. potassium, phosphorus and calcium as well as the red and white blood cell counts can also be important in order to determine the best course of treatment.

Could the renal failure have been diagnosed earlier?

Unfortunately, this is very difficult as neither clinical signs of renal failure nor rises in BUN and creatinine are evident until significant loss of kidney function has occurred. In earlier stages of disease there are no clinical signs to indicate that sophisticated renal function tests, which can pick up early renal damage, are required. We recommend that all senior pets have at least annual urinalysis to diagnose kidney disease at it earliest detectable level. A low urine specific gravity may indicate that at least two-thirds of the kidney tissues are damaged.

How does CRF affect my cat?

Because the kidneys perform a variety of different functions, the clinical signs of renal failure can be somewhat variable. The most common changes seen are weight loss, poor hair quality, halitosis (bad breath), variable appetite which may be associated with mouth ulcers, lethargy and depression. Less commonly, cats are seen to drink and urinate more and some will have vomiting and diarrhea. Rarely, renal failure is seen as sudden onset blindness.

What treatments are available?

Depending on the results of blood tests your veterinarian may be faced with several problems that require different treatments. Don't worry if the list below seems so long that you will never be able to administer all of the medications. The majority of cats can be effectively managed with diet change including supplementation and one or two other treatments.

1.       Lowering the level of waste products in the bloodstream by feeding low protein and low phosphorus diets. These can be prepared at home or are available ready prepared from your veterinary practice. The palatability of reduced protein diets is usually not as high as normal cat food, so you may have to persevere for a while before your cat will eat it.

2.       Phosphate binders - despite low phosphate in the diet, blood phosphorus levels remain above normal in some cats. Reducing blood phosphorus can have a major effect on improving your cat's well being and slowing disease progression. Phosphate binders such as aluminum hydroxide are given by mouth to further lower the amount of phosphorus absorbed through the gut wall.

3.       Antibiotics - many cats seem to respond well to antibiotics though the reason for this is not always clear.

4.       Potassium supplementation - cats in renal failure tend to lose too much potassium in the urine. This leads to muscle weakness, stiffness and poor hair quality. Low potassium levels may also contribute to the worsening of the kidney failure.

5.       Vitamins B and C - these vitamins are lost by the failing kidneys and need daily supplementation.

6.       Anti-emetics - for those cats that are experiencing vomiting, the use of anti-emetics reduces nausea, thereby improving appetite.

7.       Hypotensive drugs - significant numbers of cats with kidney failure have high blood pressure. In some cases lowering their blood pressure may be necessary.

8.       Treatment of anemia - the kidneys also initiate the production of red blood cell in the bone marrow. Many cats with CRF are anemic due to a lack of stimulation of the bone marrow. Newer drugs have been developed to help stimulate bone marrow production and may be prescribed for your cat.

IT IS IMPORTANT THAT FRESH WATER IS AVAILABLE AT ALL TIMES BECAUSE CATS WITH RENAL FAILURE TEND TO DEHYDRATE RAPIDLY.

What is the cost of treatment?

Treatment costs will vary with each individual case. In the majority of cases, long term management is unlikely to be prohibitively expensive.

How long can I expect my cat to live?

Unfortunately, once the kidneys are damaged, they have very limited ability to recover. Most CRF advance very slowly. With treatment, your cat may have several years of good quality, active life ahead.

What is FLUTD?

FLUTD, a common health problem of domestic cats, is characterized by blood in the urine, pain while urinating, urinating more frequently, passing only a small amount of urine and actual urethral obstruction. Early on, some housebroken cats may begin urinating in unusual locations.

Which cats become affected?

Cats, both male and female, between the ages of 2 and 6 years are most often affected by FLUTD. Female cats rarely obstruct because of the larger diameter of the female urethra.

What are possible causes of FLUTD?

Although research efforts to determine the cause of FLUTD are ongoing, the exact cause or causes remain unknown. It is felt that a combination of factors may be responsible for FLUTD. The factors include: lack of water intake, high stress, diets high in mineral content, narrow male cat urethras, viruses or bacteria and urine retention changing the urine pH. During episodes of FLUTD, a combination of the above factors may lead to formation of crystals in the cat’s bladder. These crystals irritate the bladder wall, leading to a possible obstruction of the urethra. Another possible outcome is inflammation of the bladder without any identifiable cause, now termed "interstitial cystitis."

What are the signs of urethral obstruction?

Signs of an obstruction include vomiting, lack of appetite, listlessness, dehydration, a firm, distended bladder in the abdomen, abdominal pain, convulsions and finally coma.

What does a veterinarian do to treat a cat with FLUTD?

If a cat is in the early stages of FLUTD, the first diagnostic procedure is to obtain a sterile urine sample. A culture and sensitivity test is often run on the urine to determine if bacteria are present (a rare occurrence in a cat). Sometimes a veterinarian will recommend a dietary change. Antibiotics are prescribed if bacteria are identified. If a urethral obstruction is present, it is an emergency and immediate treatment is necessary. Catheterization of the bladder, fluid therapy and other supportive care is in order. Surgery may be required if catheterization fails or repeated episodes of urethral obstruction occur. In some cases urethroscopy and cystoscopy using a rigid endoscope may be recommended.

How can another episode of FLUTD be prevented?

Your veterinarian will recommend a diet appropriate for you cat’s specific problem.

Provide clean, fresh water daily (distilled if your water has high minerals).

Change the litter box frequently.

Prevent obesity. Encourage exercise.

Minimize stress such as a change in environment or temperature.

Follow directions on giving appropriate medications prescribed by your veterinarian.

        Be sure to bring your cat in for annual examinations.

Leptospirosis confirmed in a Care Animal Hospital patient

Pepper, a seven year old spayed female schnauzer, recently came to Care Animal Hospital after her owner noticed she hadn’t eaten for three days and was having diarrhea. She was jaundiced (had yellow discoloration to her gums and the whites of her eyes), had diarrhea and was quite subdued. Blood tests showed severe kidney and liver damage, as well as a very high white blood cell count. She was hospitalized for a week on IV fluids and antibiotics while we sought a diagnosis for her very serious illness. After extensive research and discussions with infectious disease specialists in several states, we confirmed that Pepper was infected with Leptospirosis. She is now convalescing at home and it is hoped that she will have a full recovery from this devastating disease.  As of Monday, 8/30/04, she is doing better and is expected to pull through.  Leptospirosis has never been diagnosed in a Care Animal Hospital patient before. Positive dogs have been identified this summer in Boulder and in Lakewood . We wanted our clients to be aware of the disease, its transmissibility to humans and the vaccine that protects against it.

Where does it come from? Leptospirosis is a bacterial disease of the genus Leptospira that affects humans and some other animals (but not cats). Transmission to humans from animals does occur, through the urine of the infected animal, and the disease is serious but treatable. Outbreaks of leptospirosis are usually caused by exposure to water contaminated with the urine of infected animals. Many different kinds of animals carry the bacterium. The cases in Colorado seemto be linked to exposure to urine or water contaminated with urine of infected raccoons  You can't look for "sick" raccoons - many animal carriers of leptospirosis show no symptoms. Outbreaks of human and canine leptospirosis have been associated with periods of heavy rainfall and flooding. Our increased rainfall this summer may be the reason this disease is presenting itself. Pepper did not drink from an outdoor watersource, but there are many raccoons in this client’s backyard and surrounding area.

What about a vaccine? A safe and effective vaccine for leptospirosis is available and is given regularly in states where the disease is more common. Vaccination is recommended for dogs that frequent areas that have a lot of raccoon “traffic”. If your dog drinks water from creeks or ponds that could have been visited by raccoons, you should highly consider vaccination.
The dog receives two injections in the first year, spaced two to four weeks apart, and a booster in each subsequent year. We ask that you wait 15 minutes after your dog is vaccinated to be sure there are no signs of a vaccine reaction.

Questions about all of this? Leptospirosis is a serious disease, but it has been controlled and treated for many years in other areas. Those of us who own dogs in the Arvada area should not be alarmed about Leptospirosis, but we should be informed. As with any concerns, you are always welcome to call or stop in to discuss your situation with our technicians or our veterinarians.  If you would like more information, please check out the following links.

The Center of Disease Control
Cornell Chronicle