Renal Transplant in Dogs

The kidneys perform a number of vital roles such as reclaiming water, filtering toxins out of the bloodstream, and producing urine which is voided from the body. When kidneys fail, the dog becomes very sick because of a buildup of toxins and other effects such as anemia and mineral imbalances.

Renal transplantation is a complex surgical procedure which involves harvesting a healthy kidney from a donor dog and implanting it into the dog with renal failure. This is a deep specialist procedure which is undertaken at only a few select vet hospitals. Even then, the success rates are low with the University of California at Davis citing a 40% positive outcome. 

Renal transplant is only considered for patients with severe renal failure, and then only if the patient meets with rigorous screening tests in an attempt to maximize the chances of success. 

Both the recipient and the donor dog must be carefully screened prior to surgery. This includes checking they are free from infectious disease and parasites (including heartworm), checking their ability to clot blood, and that they are free from heart disease, cancer, or inflammatory bowel disease. 

The recipient also needs to be stabilized ahead of surgery, which can include a blood transfusion to reverse renal-related anemia. 

Under the strictest aseptic conditions, a team of surgeons harvest the donor organ from a living dog under anesthetic. The donor dog is then woken and sent to recovery. 

Again under strict aseptic conditions, the recipient is given an anesthetic and their abdomen clipped and surgically scrubbed. Via a long incision in the belly, the internal organs are held aside with retractors to access the kidneys. An unhealthy kidney is removed, and the replacement kidney attached to the renal artery and vein. 

Once the surgeon is satisfied the kidney is being adequately perfused, the abdomen is closed and the patient woken and sent to recovery. 

Unfortunately, even a successful renal transplant means the dog must take immunosuppressive medications for the rest of their life (although new techniques are being pioneered). When the body doesn't reject the grafted kidney, this can be life-saving for the patient and stop them from dying prematurely from kidney failure. 

However, the success rate of 40% must be balanced against a failure rate of 60%, where the organ is rejected and the patient reverts to kidney failure and requires euthanasia. 

Alternatives to transplantation include aggressive medical management of kidney failure. This include intravenous or subcutaneous fluids, blood transfusions, erythropoietin supplements to stimulate blood cell production, phosphate binding drugs, ACE inhibitor medications, anti-nausea drugs, and prescription diets. However, once diagnosed with renal failure, dogs tend to deteriorate more rapidly than cats, even with gold standard medical care. 

The recipient remains on intravenous fluids after surgery, in order to support perfusion of the new kidney. Pain relief is administered, along with medications to prevent organ rejection. Close monitoring is required, via blood and urine tests, to check the function of the new organ. The skin sutures are removed after 10 to 14 days. 

If all goes well, the dog can be discharged and monitored on an outpatient basis. This includes blood tests to look at toxin levels in the bloodstream, and urine tests to help check renal function. 

Renal transplant is extremely costly, with centers requiring a $13,000 deposit ahead of surgery, with the operation costing upwards of $20,000. However, the cost of the operation is just the beginning, because immunosuppressive drugs are expensive, with around $11,000 per year for a large dog being representative. In addition, there will be the cost of blood and urine tests on an ongoing basis. 

There are considerable ethical dilemmas centered on the efficacy of renal transplantation in dogs. For example, there is the conundrum of harvesting a donor organ from a dog who cannot give their consent. Unlike in the human world of transplantation where patients give consent in advance and organs harvested from the brain dead, in the canine world perfectly healthy animals must donate regardless of their wishes. 

This also raises the question of what happens to the donor dog afterwards. Morally, it should be incumbent on the owner of the recipient to then adopt the donor, but not all dogs get along...

That aside, such major surgery needs careful consideration, especially when the success rate is relatively low. 

Dogs identified with cystic kidneys should not be bred from, so as to eliminate the possibility of future generations being affected. Care should also be taken to vaccinate (on a risk assessment basis) the dog from conditions such as leptospirosis which can cause kidney failure. Vigilance and supervision is also recommended, to prevent the dog drinking antifreeze or medication which could be harmful.