Bladder stones in dogs are also known as urinary calculi, and may be due to deposits of minerals from the urine. Stones can be present in the dog's urinary tract, but they're usually located in the urinary bladder.
Types of Bladder Stones
The bladder stones may form over time, due to the composition of urine that leads deposits of minerals or other compounds. The main types of bladder stones are divided in groups depending on their chemical composition:
- Struvites are bladder stones made up mostly of magnesium crystals
- Calcium oxalate stones
- Calcium phosphate stones
- Ammonium urrate
Some bladder stones in dogs will contain a combination of several of the above mentioned crystals. The composition of these bladder stones can be established only if the dog has eliminated a stone and this is analyzed. A urine test may sometimes determine the possible composition of the stones. For instance, a dog with alkaline urine is likely to have struvite stones, while an acidic urine can indicate the dog has calcium oxalate stones in the bladder.
Symptoms of Bladder Stones
When a dog has urinary calculi, he will display a few of the following symptoms:
- Straining to urinate and urination in smaller amounts
- Blood in the urine
- More frequent urination
- Excessive licking of genital area
The stones may be felt when palpating certain areas of the abdomen, especially if the stones are larger. Bladder stones in canines can get up to 3 to 4 inches in diameter.
Causes of Bladder Stones
Bladder stones can develop due to:
- Genetic predisposition
- A diet that is rich in minerals
- A supplementation of minerals the dog cannot assimilate and eliminate through urine
- Frequent urinary infections, which make the urine alkaline
Treatment for Bladder Stones
The treatment for bladder stones in dogs will depend on the type of stones found in the urinary tract, as well as the location and size of the stones. A change in the dog's diet can be a solution to dissolve the existing bladder stones. Medication treatment is available for bladder stones, but may only be applied if the stones are struvite or ammonium urrate formations. Surgery is a more extreme treatment option, but it may be necessary, especially if the bladder stones cause urinary blockage or other problems in the urinary tract. This type of surgery is known as cystotomy.
Urohydropropulsion is another solution to eliminate bladder stones. It involves filling the bladder with a saline solution and using a catheter to push the solution back and forth until the stones are expulsed. This type of treatment is recommended for calcium oxalate stones that cannot be eliminated through diet or medication.
The bladder stones may also be eliminated without any treatment by increasing the liquid intake of the dog, but the vet will monitor the pet and if the stones are not eliminated in a few weeks, surgery will be recommended.