Urinary Incontinence

Dogs and cats that are unable to willfully control their urination habits are said to be suffering from incontinence. Pets with urinary incontinence might simply urinate spontaneously without warning, or might drip urine continuously throughout the day. Inappropriate urination while sleeping is another common complaint. Dermatitis in the genital and hind-leg regions can also be seen as a result of incontinence and urine scalding in these areas.

The potential causes of urinary incontinence are numerous; as a result, a proper veterinary workup is essential to obtain a correct diagnosis. Spinal trauma, anatomical changes or irritation caused by inherited defects, infections, tumors, urinary calculi, and metabolic diseases such as diabetes mellitus or diabetes insipidus can all be underlying causes of incontinence. In these instances, treatment is geared toward correcting the underlying cause if possible. It has been noted that a small number of female dogs that are spayed at an early age can suffer from incontinence when they enter their geriatric years. Although the exact cause of this incontinence is unknown, it can usually be controlled with medications designed to increase sphincter tone within the lower urinary tract.

Puppies and even some adult dogs might urinate spontaneously when they become excited or frightened. Most puppies will “grow out” of this problem as they mature. For these and others, treatment for behavioral incontinence is directed toward minimizing the stimuli that cause the incontinence in the first place. For instance, when dealing with dogs that urinate because of excitement, avoiding eye contact or exaggerated greetings when approaching the pet often help curb excitement and prevent urination. For those dogs that urinate when frightened, easing their fear through behavioral modification is the key to a cure.

Feline Lower Urinary Tract Disease (FLUTD)

Feline lower urinary tract disease [known in the past as feline urologic syndrome (FUS)] is a disease syndrome of cats characterized by the formation of crystals (the most common are struvite and calcium oxalate crystals) within the urinary bladder. These crystals, in turn, cause inflammation, urinary bleeding and straining, and sometimes life-threatening obstruction to the normal flow of urine out of the bladder.

No one knows for sure why some cats get FLUTD and others don’t. Many potential causes have been hypothesized, including viruses, abnormal urinary retention, obesity, bladder defects, and—the most popular theory to date—improper diet. In reality, one or all of these factors might play a role in the occurrence of FLUTD.

If a cat is prone to this disorder, it will usually show some signs of the disease by the time that it is 3 years of age. Both male and female cats are at risk of developing FLUTD; however, males have a greater likelihood of developing a life-threatening obstruction simply because the male urethra is smaller than that of the female and can become plugged with crystals more easily. If such an obstruction occurs, urine can flow back into the kidneys, causing damage to these organs and also causing toxins to begin building up in the bloodstream.

Early clinical signs of FLUTD result from the irritation that these crystals cause within the bladder itself. These can include inappropriate urination in places other than the litterbox or normal elimination areas, increased licking at the genital region, straining, frequent attempts at urination with crying or vocalization, and blood in the urine. Cats often lose their appetites and become more irritable as well. More seriously, male cats suffering from partial or complete obstruction of the urethra can exhibit vomiting, intense lethargy, and a distended, painful abdomen.

Diagnosis of FLUTD is based on clinical signs, physical examination, and a urinalysis. An enlarged, painful bladder can also be palpated in those cats suffering from some degree of obstruction. If a bladder infection is suspected, then urine cultures might also be performed.

The obstructed cat will usually have high levels of kidney enzymes (BUN, creatinine) present in its bloodstream, signifying the toxin buildup and kidney destruction that is occurring. Most veterinary hospitals are equipped to monitor these enzymes.

If an actual obstruction is suspected, then rapid treatment is essential to save the life of the cat. Obstructed cats are immediately placed on intravenous fluids to help dilute the toxin levels within the bloodstream. A catheter is then inserted into the urethra to “unplug” it in order to reestablish urine flow. Once this flow is reestablished, the bladder is flushed repeatedly with sterile saline to remove any crystals that might be remaining within.

The veterinarian must decide whether to keep the urinary catheter in place for a few days. While catheterized, these cats are placed on antibiotics to prevent the occurrence of any secondary bladder infections as a result of the catheter. Intravenous fluids are continued in the hospital setting for 2 to 3 days after the obstruction is relieved.

For the cats that are not obstructed but still are showing signs of FLUTD, smooth-muscle relaxants and anti-inflammatory medications can be used to help reduce the discomfort and urge associated with this disease. The use of antibiotics in such patients is still controversial; studies have shown that bacterial infections are present in less than 20 percent of the cases. However, if urine culture confirms the presence of such, antibiotics are, of course, indicated.

If struvite crystals have been diagnosed, altering the pH of the urine in order to dissolve any crystals present within the bladder is another important step in treating this disease in both obstructed and unobstructed felines. Rendering the urine more acidic will help dissolve existing struvite crystals and help prevent the formation of new ones.

Most veterinary researchers agree that diet plays the foremost role in the creation and in the treatment and prevention of this disease syndrome. Dry diets with high contents of magnesium and ash (mineral) levels are the biggest culprits in promoting FLUTD in cats.

Unfortunately, many of the commercial supermarket brands of cat food contain these excesses. Diets specially formulated for the prevention of FLUTD can be obtained in both moist and dry forms from most veterinary offices and some pet supply stores. Because of its high calcium and mineral content, cow’s milk should never be offered to those individuals prone to FLUTD.

Besides feeding a diet that promotes a healthy urine pH and is low in magnesium and ash, providing cats free access to a fresh water supply is a must. Increased water consumption will help increase the number of urinations each day, effectively keeping the bladder flushed out. In fact, most commercial diets formulated for the prevention of FLUTD have an increased salt content to promote increased water consumption. With these increased urinations comes the responsibility of keeping the litterbox cleaned on a regular basis. Many cats refuse to urinate in a dirty litterbox, a practice that encourages urine retention and FLUTD.

Although it might not seem important, regulating the frequency of meals fed can play a direct role in the prevention of FLUTD. After a cat consumes a meal, its urine undergoes a temporary rise in pH. For those cats allowed to eat and nibble all day long (such as those fed dry foods), this might promote relatively constant alkaline urine, and thereby predispose to struvite crystal formation. As a result, in terms of preventing FLUTD, offering one or two meals a day rather than free-choice meals is preferred.

Obese cats are more prone to FLUTD than their slimmer counterparts, so weight control is an important preventive measure to follow as well. Overweight felines, especially those who have exhibited signs of FLUTD in the past, should be placed on a reducing diet prescribed by their veterinarians and have their activity levels increased until the desired weight is reached. Once weight loss is accomplished, they can be switched back over to preventive-type rations. Without proper dietary management, FLUTD can be expected to recur over 50 percent of the time. In some cats, however, FLUTD recurs over and over again, even with dietary management. In these instances, treating the symptoms when they first appear and continuing with preventive measures will usually prevent such episodes from turning serious.

For those male cats that have had recurring obstruction, a special operation known as a perineal urethrostomy might be indicated to reduce the danger of death due to urinary blockage. This surgery involves the removal of the end of the penis and widening the urethral opening, effectively allowing for free passage out of any and all crystals. Keep in mind that such a procedure is not intended to cure the FLUTD; it merely lessens the risk of severe, life-threatening complications associated with it.

Canine Urolithiasis (Urinary Stones)

Urinary tract infections that go unnoticed for a period of time can predispose a dog to urolithiasis. A urolith or stone results from the coalescing of crystals that form within the bladder environment. In dogs, these stones form more readily within the bladder than they do in other portions of the urinary system. Urolithiasis presents itself in dogs in two forms: cystic (bladder) calculi and urethral calculi.

Cystic calculi are found mainly in females and appear when infectious bacteria within the bladder cause a shift in the urine pH, which in turn causes the crystals to form. The two most common types of crystals generated are struvite and calcium oxalate crystals. Stones formed by these crystals are often discoid in shape.

Urethral calculi occur in male dogs and are typically composed of cystine or urate crystals instead of struvite. This type of urolithiasis is seldom caused by infections; rather, an inherent metabolic disorder is responsible for crystal formation. If these stones lodge in the male urethra, they can prevent normal urination, and can seriously threaten the life of the pet.

Straining to urinate, bloody urine, constant licking at the urethral opening, and/or frequent unsuccessful attempts to urinate are all signs of a urinary problem. Stones might or might not be present in a dog exhibiting these signs, but this warrants a professional evaluation. Some dogs, especially females, might carry stones in their bladders for long periods of time without exhibiting any signs at all. This is one good reason for having a veterinarian perform a routine urinalysis on an annual basis.

Diagnosis of urolithiasis is made on the basis of microscopic examination of the urine for crystal formation, abdominal palpation, and radiographs. Most stones will show up readily on regular radiographs; however, those composed of urate or cystine might require special contrast radiographs in order to identify them. In addition, for male dogs suspected of having urethral calculi, inability to pass a urinary catheter is a sure sign that stones are present. In these cases and others, the attending veterinarian will often elect to run blood tests as well to ensure that the kidneys and other organs are functioning properly in the presence of these uroliths.

Treatment of urolithiasis depends on the size and number of the stones present and their location within the urinary tract. Obviously a male dog whose urinary tract is completely plugged by one or more of these stones requires emergency care immediately. Catheterization is performed in an attempt to dislodge the stones, pushing them back into the bladder and freeing up the flow of urine. Most of the time, these stones must then be removed from the bladder surgically. In those cases uncomplicated by obstruction, the size of the stones involved determines the treatment regimen. Large stones located within the bladder will undoubtedly require surgery for their removal.

In contrast, smaller struvite stones or crystals can often be effectively managed only with special diets designed to dissolve the stones. Typically, this dietary approach to treatment might take anywhere from 1 to 4 months to accomplish the desired results. If a pet is placed on a urolith-dissolving diet, be sure to follow the veterinarian’s instructions closely. These diets should not be administered for any term longer than that prescribed by the veterinarian. Once the stones have dissolved, the pet needs to be switched to a different diet.

Of course, whether a surgical or medical approach is used, concurrent antibiotic therapy is also necessary if an infection is underlying the bladder stones. Because the rate of recurrence of urolithiasis is relatively high even after successful treatment, preventive measures should be instituted to help lower the odds. For urethral calculi, special diets that can help promote a urine pH that is nonconducive to crystal formation are available from veterinarians. These diets are also low in those dietary components that might be incorporated into crystals.

Cystic calculi can be prevented in a similar fashion, using special diets available from veterinarians designed for the prevention of struvite uroliths. In addition, prompt identification and treatment of urinary tract infections will help ensure that crystals and stones won’t develop as a consequence

Date: 2014-12-21; view: 1193