Bladder Stones

Bladder stones are formed when excessive minerals start to crystallize, becoming larger and larger as more crystallization occurs. The exact cause of bladder stones is not fully understood, however, it does appear to be an individual dog or cat problem. Some breeds, such as Dalmations, have specific problems with stones that are somewhat unique to their breed, although not all individuals will develop those problems. Bladder stones can be divided into two groups, those that form in acidic urine and those that form in alkaline urine. The most common stones seen in acid urine are Phosphate stones, made up primarily of Phosphorous, Calcium, and Magnesium. Alkaline stones include Calcium Oxalate Stones and Urate Stones (Dalmations).
Clinical signs of a dog or cat with stones include frequent urination, blood in the urine, lower abdominal pain or discomfort, and occasionally vomiting. Male dogs are especially in a dangerous situation because of the possibility of a stone blocking their urethra, which can lead to a ruptured bladder if not relieved in a short amount of time. Stones can occur as a single large stone, or multiple small stones (I have seen dogs with over 100 small stones in their bladder). A urinalysis will detect blood, pH, protein and any crystals or bacteria that are present, but the final diagnosis is made from an x-ray of the abdomen.
Once diagnosed, the primary treatment for stones is surgical removal of the stones. Some patients with phosphate stones that have very minimal clinical signs can be treated with a special food that dissolves the stones over a 6-8 week period. Surgical removal gives instant relief and a shorter recovery time. Because a dog or cat has shown the tendency to develop stones, a special diet should be used to prevent new stones and should have urinalysis done every 6 months.