Can Dogs Get Kidney Stones?

If you are like most pet owners, your dog is just as much a part of your family as your kids.  And just like your kids, your dog can suffer from several medical issues. 

In humans, kidney stones are typically composed of a substance called calcium oxalate, but they can also be comprised of other substances. Left untreated, they can grow to the size of a golf ball. In most cases, they are small enough to pass while urinating (which can be painful), but they may also be large enough to cause intense pain and require medical treatment.

In canines, kidney stones can develop when there is a buildup of salts, minerals, and calcium oxalates causing inflammation and sometimes even a blockage of urine flow.

Can Dogs Get Kidney Stones?

Yes, just like you, your dog can get kidney stones that can grow large enough to block the flow of urine and be very painful. An x-ray can reveal the presence of kidney stones. In fact, there may be no signs of the presence of small stones until they are picked up during x-rays that have been taken for another reason.

In other cases, symptoms will be very apparent, alerting you to the fact that your dog needs veterinary attention. For example, if your dog's belly seems to be painful or they appear to be having trouble urinating, take them to the clinic immediately.

Does My Dog Have Kidney Stones?

Symptoms 

The two most common signs your dog may have kidney stones are painful urination and blood in the urine. However, there are several other signs you should be aware of, including:

• Abdominal pain

• Changes in urine output – increase or decrease

• Fever

• Lethargy

• Lack of appetite

• Weight loss

• Vomiting

• Frequent urination attempts with dribbling

Causes

The most common form of kidney stones in dogs is metabolic kidney stones. These are typically formed as the result of an imbalance in their blood or urine. These imbalances can lead to the formation of crystalline structures that will eventually become stones. Among the causes for the formation of kidney stones are:

• Elevated reabsorption of water by the kidneys

• Dehydration

• Genetic predisposal to kidney stones

• Changes in your dog's urine pH levels

• An increase in salt concentration in your dog's urine

Diagnosis

Your vet may start out by taking several x-rays of your dog's abdomen as most kidney stones will show up in the radiographic images. However, smaller ones can be harder if not impossible to see in this manner. Along with the x-rays, your vet may also run several tests including:

• A complete blood count (CBC) to check for anemia, low red blood cell or high white blood cell count

• Blood chemistry including electrolytes to check for any evidence of kidney disease

• Urinalysis to check for kidney disease and the presence of red or white blood cells

• A urine culture to check for a bacterial infection and to assist with choosing the right antibiotic

For more information on dogs and kidney stones, please see Kidney Stones in Dogs.

How Do I Treat My Dog's Kidney Stones?

The type of treatment recommended by the vet for your dog's kidney stones will vary significantly based on several factors. These include the location, size, and specific type of kidney stone. However, there are several common forms of treatment for kidney stones.

• Adjustments to diet – a special diet that is low in magnesium, protein, and phosphorus may be recommended to reduce the risk of growth and urinary tract blockage

• Medications – your vet may prescribe specific medications to help dissolve the kidney stone, along with some pain relief

• Surgery – depending on the size and location of the stones, surgery may be the only way to remove them

• Extracorporeal shock wave lithotripsy (EWSL) may be used to dissolve smaller stones instead of surgery

After the treatment, your companion will need a little downtime. Recovery from kidney stones will, in some part, be dependent on the type of treatment used to get rid of them. If the vet is using medication to destroy them, follow up visits will be needed that include x-rays to ensure the stones are dissolving. 

If surgery was performed, your vet will give a list of instructions that must be followed along with a special diet. Provided the stones have not led to kidney disease or other complications, your dog should make a full recovery. However, once your dog has had kidney stones, they will be prone to recurrence and should be checked for them frequently by your vet. 

Your vet may suggest a permanent diet change and will recommend you encourage your dog to drink water often throughout the day. Additionally, your vet may want to regularly check your dog for stone formation.

How Are Kidney Stones in Dogs Similar to Humans?

• They are the result of an imbalance in the blood or urine

• They can be very painful

• They can block the urethra, making urination painful

• They can result in reduced urinary output

• They can result in blood in the urine

• They can cause a persistent feeling of needing to urinate

• Treatments for kidney stones in both humans and dogs are very similar

How Are Kidney Stones in Dogs Different Than in Humans?

For the most part, kidney stones in humans and dogs are very similar. The biggest difference is that dogs are more susceptible to them than humans. There are, however, a few other differences you may not be aware of, including:

• Checking for kidney stones is often part of an annual checkup for dogs

• X-rays have been in use to detect kidney stones in humans for decades, but have only recently started being used for dogs

• In humans, males have a higher incidence of kidney stones. In dogs, females are the ones who are more likely to have kidney stones.

Case Study

Sasha, a 7-year old Yorkshire Terrier was taken to the Ryan Veterinary Hospital in Florida suffering from a very large kidney stone. She was sent the University of Pennsylvania Hospital for treatment. The veterinary team used a combination of treatments including fluoroscopy, percutaneous nephrolithotomy and ureteral stenting to diagnose and then treat the stone by breaking it up using endoscopic surgery. The results were good and the prognosis excellent. What made this case unique was that this was the first time these procedures were used to treat a dog for kidney stones. Once the procedure was complete, a ureteral stent was installed to protect the dog's ureter and reduce the risk of any post-procedure complications.