Depending upon their composition, stones in the urinary tract can be either dissolved with diet and medical management or removed surgically. The best treatment option is to detect and remove the stones before they cause a physical blockage. Once obstruction occurs, mechanical removal of stones is almost always necessary.
Sometimes, urinary stones can be removed with a nonsurgical procedure called urohydropropulsion. This is more commonly done in female dogs, based on their anatomical differences from males. During this procedure, the dog is sedated, a urinary catheter is inserted into the urethra, saline fluid is flushed through the catheter into the bladder, and then the bladder is squeezed to flush out the stones if possible. Alternatively, abdominal surgery is performed to remove the stones directly from the bladder. Abdominal radiographs will be taken before and after the procedure to determine whether all of the stones were successfully removed. Antibiotics may be appropriate if infection is suspected.
Some stones, particularly cystine stones, can actually be dissolved medically through a protein-restricted diet, administration of dietary supplements to reduce the acidity of the urine and maintenance of good hydration. Administration of a product known as 2-MPG can increase the solubility of cystine stones and prevent their recurrence. There can be side effects from this product; as always, discuss all treatment options thoroughly with your veterinarian.
When a dog has large stones or a large number of stones, it is unlikely that non-surgical options will be successful in removing those stones from the urinary tract. Similarly, in cases of complete blockage, there simply may not be time to try urohydropropulsion. In these cases, traditional surgery is required. The surgical procedure is called a “cystotomy,” and it is performed under general anesthesia. The veterinary surgeon will make an incision through the skin and abdominal wall, and then will make a much smaller incision directly into the bladder. She will physically remove the stones and then close the bladder, abdominal tissues and skin with appropriate suture material and techniques. This procedure is normally very successful and is about as invasive as a spay procedure in female dogs.
Once the stones are removed from the bladder or from wherever else they were lodged, they will be sent to a laboratory to determine their actual composition. This information will help the attending veterinarian identify why the stones formed and how they might be prevented in the future. The recurrence of certain types of stones can be reduced by placing the dog on a special diet and ensuring that electrolytes and fluids are well-balanced.
The prognosis for dogs with urinary stones is good as long as the condition is detected and treated appropriately. Dogs with complete blockages obviously have a more guarded prognosis than do those only with crystals in their urine or with stones that remain in the bladder itself. However, in both cases, medical management and surgery are available that can be quite successful in resolving any crisis and regulating the condition for the duration of the dog’s life. Recurrence of stones is common.