By petMD Sep 25th 2013

By Lorie Huston, DVM

Feline lower urinary tract disease (FLUTD) is commonly diagnosed in the cat and can have a number of different causes. Previously referred to as feline urologic syndrome (FUS), feline lower urinary tract disease involves, as the name implies, the structures that make up the lower portion of the urinary tract. These structures include the urinary bladder and the urethra (the tube that carries urine from the bladder to the outside of the body).

Is FLUTD the Cause for Urinating Outside the Litter Box?

Unfortunately, urinary tract disease often leads to inappropriate urination, or urinating outside of the litter box. Urinating outside of the litter box is not always a medical issue but, either way, not using the litter box is one of the most common reasons cats are relinquished to animal shelters. Many of these cats are euthanized in shelters as a result of being unable to place them in an appropriate home.

Potential causes of lower urinary tract disease in cats include: 

–Bladder stones
–Bladder infection
–Interstitial cystitis (inflammation of the bladder)
–Urethral obstruction (may be caused by stones in the urethra or by plugs within the urethra made up of organic debris such as cells, proteins, and minerals. Less commonly caused by tumors or other physical abnormalities in the urethra.)

Interstitial cystitis is a disease of exclusion. It is diagnosed by ruling out other potential causes of urinary tract disease. This form of urinary tract disease is believed to be related to stress. It causes inflammatory changes within the bladder and results in the same types of symptoms seen with other forms of lower urinary tract disease. Many veterinarians believe that interstitial cystitis is actually only the most easily recognized abnormality caused by stress in cats and that the disease is actually asystemic disease affecting more than simply the urinary tract.

Urethral obstruction is the most serious form of urinary tract disease. Urethral obstructions almost always occur in male cats because the urethra in the male cat is much narrower than that of the female cat. Female cats rarely develop urethral obstructions and, when they do, the cause is usually a tumor or other space-occupying mass that obstructs the urethra. In the male, small bladder stones often cause an obstruction as they pass out of the bladder and through the urethra. Plugs can also occur in the male cat causing an obstruction.

Cats that are obstructed are unable to urinate. Normal healthy cats rid themselves of their body’s waste products through their urine. Obstructed cats are unable to get rid of these waste products. They become toxic very quickly as the waste products begin to accumulate in the bloodstream. These cats essentially end up poisoning themselves with their own body waste as a result of their inability to urinate.

The symptoms of urinary tract disease include: 

–Straining to urinate (dysuria)
–Frequent attempts to urinate
–Painful urination
–Bloody urine (hematuria)
–Lack of appetite
–Irritability
–Urinating outside the litter box

Cats that suffer from a urethral obstruction will actually be unable to urinate. Symptoms may appear similar, with frequent attempts to urinate, straining, and pain. As the disease progresses, the cat will begin to vomit and will become very depressed and lethargic. If not treated, urethral obstructions are usually fatal.

If your cat is exhibiting symptoms of urinary tract disease or you suspect something is wrong, you should schedule an appointment with your veterinarian. If your male cat is not urinating, the situation is an emergency and your cat needs veterinary care immediately.

Treatment of urinary tract disease depends to some extent on the cause of the disease: 

–Cats suffering from a urethral obstruction will need to have the obstruction resolved via the passing of a catheter through the urethra and into the bladder, relieving the obstruction. Supportive care such as intravenous fluids and monitoring of kidney function and blood electrolyte levels will likely be necessary also.
–Antibiotics are used to treat bladder infections, if present. Bladder stones sometimes require surgical removal. In other cases, therapeutic diets may be an acceptable alternative to surgery. Often, a therapeutic diet will be recommended even after surgical removal of bladder stones to keep additional stones from forming. Your veterinarian will help you decide what is best for your cat.
–Water consumption should be encouraged. All cats should have fresh water available at all times. Water fountains and dripping faucets can entice some cats to drink more water. Feeding canned food is an alternative also because of the increased moisture content in wet food. Some cat owners also add additional water to their cat’s food.

–Environmental enrichment should be used to reduce stress for indoor cats. Enrichment includes toys, perches, hiding places, scratching surfaces, and other items to entertain your cat and make him/her feel safe.
–Litter boxes should always be kept clean and care should be taken that your cat is not disturbed or harassed while using the box. In multi-cat households, an adequate number of litter boxes must be provided.

Preventing urinary tract disease is not always possible. However, encouraging water consumption, environmental enrichment, and proper litter box care can help. If your veterinarian recommends a therapeutic diet for your cat, you should continue with the diet unless your veterinarian indicates otherwise. Do not change your cat’s diet or stop the therapeutic diet without consulting with your veterinarian first.