Penn Vet’s feline kidney transplant program has given cat lovers hope since 1998.
In 1998, a couple from Springfield, Pennsylvania, brought their sick cat to the University of Pennsylvania School of Veterinary Medicine. The 11-year-old cat named Leo was so weak from kidney disease he could barely walk. He became the first patient of Penn Vet’s brand-new feline renal transplant program and was soon well enough to go home [“Gazetteer,” Nov|Dec 1998].
Twenty-five years later, cat owners now come to Penn Vet from across the country and around the world seeking kidney transplants for their ailing pets. More than 180 cats have received the lifesaving surgery and go home with a new friend—the cat who donated the kidney.
“Chronic kidney diseases, unfortunately, are very common in cats and we see many different causes of kidney failure in cats,” says Lillian R. Aronson V’92, founder and coordinator of the Renal Transplant Program and professor of surgery at Penn Vet. “Why cats are more prone [to kidney diseases] is hard to say.”
Medical management is the only treatment for kidney failure other than a transplant. “Our goal was to find a treatment option that may improve the quality of life and longevity of these patients,” she says.
The survival rate for cats that undergo a kidney transplant at Penn Vet is quite good. Aronson says 92 percent of patients recover sufficiently to return home. Between 60 and 70 percent of those cats live at least a year following the transplant and some even get another decade of life.
According to the American Society of Veterinary Nephrology and Urology, Penn Vet is one of only three veterinary hospitals in the US that perform feline kidney transplant surgeries, along with the University of Wisconsin and the University of Georgia. Cat owners from around the country come to Penn for its kidney transplant expertise. People have also come from as far away as Kuwait and Brazil.
Aronson has run the feline kidney transplant program since its inception. After graduating from Penn Vet and completing her internship there, she did a four-year surgical residency at the University of California at Davis, where she learned how to perform a feline kidney transplant. “I was really fascinated with the microvascular surgery and the intricacies of working under a microscope,” she says.
After coordinating UC Davis’s transplant program for two years, Aronson returned to Penn Vet in 1997 and successfully pitched the idea of starting the school’s own feline kidney transplant program.
Performing a kidney transplant on a cat is technically challenging and requires a team of surgeons, anesthesiologists, and nurses. The procedure takes six to eight hours and most of it is under an operating microscope, so there’s very limited room for error, explains Aronson. “I think what makes it so challenging is just the sheer size of the vessels that we’re working with,” she says. “So, for example, the internal diameter of a cat renal artery—the artery that supplies the kidney—is maybe two millimeters. The vein is maybe four millimeters and the ureter, 0.3 millimeters. It doesn’t take much to have a problem.” Adding to the challenges, two surgeries are going on nearly at the same time, one to remove a kidney from the donor cat and one to transplant it into the recipient.
One of the most frequently asked questions about the program is where the donor cats come from and what happens to them post-surgery. Penn Vet works with a local animal rescue that provides healthy, adoptable cats to donate one of their kidneys. Donors must be the same blood type as the recipient but don’t need to be related to the recipient. (Dogs, on the other hand, need a compatible canine relative to donate a kidney, which makes the transplant process far less common.)
Donor cats generally do just fine post-surgery. Aronson says Penn Vet has followed 100 donor cats and found their quality of life going forward to be very good. “We are just as concerned about the donor’s well-being as the recipient’s well-being,” she says. “We don’t see an increased incidence of kidney disease in this population. They live a normal life with one kidney and really thrive.” Just as importantly, donor cats get a forever home with the family of the kidney recipient.
Back in 1998, a feline kidney transplant cost approximately $5,000, including pre-operative care, the surgery, and recovery. Aronson estimates the procedure these days costs up to $20,000, assuming no complications occur. For pet owners, it’s a matter of priorities. “A lot of clients are people whose pets are their children, and they save their money for their pets,” says Aronson. “I’ve had clients tell me: ‘I don’t buy materialistic things. This is where I want to invest my money.’”
Clients are informed about the potential complications, long-term management of kitty patients, and Penn Vet’s experience with kidney transplant patients, notes Aronson. However, she adds, Penn Vet won’t move forward with a potential kidney transplant patient if the cat is not a good candidate for the surgery. “I’ve turned people down because our goal is to improve the quality of life of the patient, and if we don’t feel that [the surgery] is in the animal’s best interest, I will tell someone that,” Aronson says.
A cat could be turned down for a kidney transplant for a number of reasons. For example, a cat that fights taking pills would not be a good candidate because kidney transplant recipients must take antirejection medication every day for the rest of their lives. A cat with a significant comorbidity—another disease or medical condition—might also be turned down.
On the other hand, Penn Vet has also learned over the years that an underlying comorbidity may improve if the cat gets a new kidney. Aronson recalls reluctantly approving kidney transplant surgery for a cat with both a failing kidney and heart disease. It turned out that receiving a fully functioning kidney resulted in less stress on the cat’s heart.
“I think I’ve learned a lesson with every case,” says Aronson. “Every time I think I’ve seen just about everything, something unique pops up. I feel like these cases, just like any cases here at the hospital, are learning opportunities.”
—Samantha Drake GGS’06