What You Need to Know About Bladder Stones In Dogs

Bladder stones, or uroliths, are stone-like mineral deposits that form in the animal's urinary bladder. Bladder stones may occur as a single deposit or as many, smaller pieces. They can be large and take up most of the bladder, or they can be fine particles that are passed when the animal urinates.

Are Bladder Stones Like Kidney Stones?

No- Kidney stones are mineral deposits that occur in the kidney. They are not as common as bladder stones and may not require immediate attention as bladder stones do. Kidney stones are usually not related to bladder stones.

Can Bladder Stones Cause Problems For My Dog?

Yes- the two most common signs of bladder stones are blood in the urine and straining to urinate. The blood is the result of the stones rubbing against the bladder wall. The straining results from the irritation to the bladder and urethra or from small stones or sand passing out of the bladder when the animal urinates. If the stones move out of the bladder and get stuck in the urethra then an obstruction will occur. This is a painful, life-threatening condition. If the obstruction is not quickly relieved then the bladder can rupture and the dog will die. If you suspect a problem, you should contact your veterinarian immediately.

Are All Bladder Stones the Same?

No- There are several types of bladder stones and each has distinctive properties. One of the most common types is the struvite stone, which consists of magnesium, ammonia, and phosphorus. Another type is the urate stone; urate stones are commonly found in Dalmatians, which have a genetic enzyme deficiency that leads to their formation. A third common stone is the oxalate stone, which is composed largely of calcium. Though there are other types of stones, they are considerably less common.

What Causes Bladder Stones?

There are several factors that lead to the formation of a stone. If the mineral content of a dog's diet is not right for that particular individual, crystals can form in the urine. These crystals may irritate the bladder wall and cause bleeding. The crystals combine with blood and mucus from the nidus, the core around which the rest of the stone forms, to form full-fledged stones. Bacterial infection may also play a role in the formation of stones as well as the pH, or acidity, of the urine. Bacterial growth is favored if the urine is alkaline rather than neutral or acidic. These bacteria coupled with crystals that can form in an alkaline environments facilitate stone formation, particularly the formation of struvite stones. Heredity, diet, and general health may each contribute to the problem as well.

How Long Does it Take For a Stone to Form?

It will depend on how many crystals are present, how bad the bladder infection is, and the pH of the urine. Stones can form in as little as a few weeks. More typically, though, the problem develops over a few months.

How Do I Know If My Pet Has a Stone?

The same symptoms that occur with a bladder infection may occur with bladder stones, specifically, straining to urinate and blood in the urine. Sometimes, if the stones are large enough, your veterinarian can feel them through the abdominal wall; however, an inability to feel stones does not rule them out as a possible diagnosis. Most bladder stones can be seen on an x-ray or with ultrasound. Some stones may not show up on an x-ray. In those cases, they can be seen by placing a dye that shows up on x-rays into the bladder. Your veterinarian has the training and equipment to make a definitive diagnosis.

Can Bladder Stones Be Treated?

Yes, there are several methods used depending on the type of stone and the severity of the problem they are causing. The quickest way to resolve the problem is to remove the stones surgically. The veterinary surgeon opens the abdominal cavity, localizes the urinary bladder, opens the bladder and removes the stones. The bladder and urethra are then flushed to remove any sand present. Another option is to dissolve the stones with a special diet. The type of diet depends upon the type of stone. This method avoids surgery but cannot be used for all types of stones. A third method is to place a urinary catheter in the bladder and hydropulse, or flush the stones out. This method is only successful if the stones are very small. Once the stones have been removed, your veterinarian can have them analyzed and make recommendations to keep the stones from reoccurring.

How Can Bladder Stones Be Prevented?

Prevention is always preferable to curing diseases. Your pet should always have plenty of clean, fresh water available. Just as important is the opportunity for your pet to pass urine. Frequent walks allow the animal to urinate and flush bacteria and crystals from the bladder. Your veterinarian may recommend a urinalysis as part of the annual physical your pet receives. This is the best way to detect a problem before it gets out of hand.

We hope this article helps you to prevent bladder stones from afflicting your pet or to recognize them and reduce the risk they pose. For more information on which veterinary diets and medications can help with bladder stones in your dog, we encourage you to reach out to our staff at the e-mail below.