Urinary stones (Bladder Stones) in Dogs

Urinary stones medically known as cystic calculi or uroliths are a collection of minerals, ranging in size and composition, that develop in a dog’s bladder and can cause frequent urinary tract infections, pain, and obstruction of the urinary tract. However, dogs with bladder stones may not show obvious clinical signs.

Bladder stones can cause a variety of problems for dogs, from discomfort and incontinence to dangerous blockages of the urinary tract. If you suspect that your dog has developed bladder stones, you’ll want to get the condition checked out and treated by a skilled veterinarian earlier rather than later to avoid complications.

Types

Most common types of stones include; 

• Struvite. The most common bladder stones found in female dogs. According to clinical studies, up to 26% of Urinary stones have been found to contain struvite.
• Calcium Oxalate. Most commonly found in males (73%). High-risk breeds include; Lhasa Apsos, Shih Tzus and Bichon Frises.
• Cystine and Ammonium Urate. Most commonly diagnosed in breeds such as; Dalmatians and English Bulldogs, urate bladder stones account for around 5% of diagnoses in dogs. 

Causes of Urinary Stones in Dogs

In general, conditions that contribute to stone formation include:

• a high concentration of salts in urine
• retention of these salts and crystals for a certain period of time in the urinary tract
• an optimal pH that favors salt crystallization
• a scaffold for crystal formation
• a decrease in the body’s natural inhibitors of crystal formation.

The sequence of events that triggers stone formation is not fully understood. High dietary intake of minerals and protein in association with highly concentrated urine may contribute to increased saturation of salts in the urine. Disease conditions such as bacterial infections in the urinary tract can also increase urine salt concentration.

Signs of Bladder Stones in Dogs

Dogs with bladder stones may display signs associated with a lower urinary tract disease, or they might not show any signs at all. Signs that your dog may have a bladder stone include:

• Straining to urinate
• Bloody or discolored urine
• Pungent urine
• Needing to urinate more often than usual
• Having accidents in the house
• Licking their genital area more than usual
• Having lower energy or a reduced appetite
• Vomiting

Daignosis

Your veterinarian can use diagnostic imaging methods to view the inside of your dog’s bladder in the search for stones. Since canine bladder stones don’t always show up clearly on X-rays, your dog may also undergo ultrasound imaging or the injection of a special dye that makes the bladder stones easier to see.

Treatment of Urinary Stones in Dogs

If struvite is the diagnosis, a veterinarian will treat the underlying cause (e.g., dog antibiotics for urinary tract infections) and may recommend a therapeutic diet that will dissolve the stones and crystals. Dogs prescribed antibiotics will typically use the drugs while consuming the therapeutic dog food, and possibly longer if needed. Surgery or other procedures like lithotripsy (breaking up the stones with ultrasonic shock waves) will be necessary to get the stones out of the bladder. The therapeutic diet for dissolving struvite stones, however, must be given under a veterinarian’s supervision.