Editor’s note: This is part two of a story that originally appeared in the May/June 2016 issue of Catster print magazine. Click here to subscribe to Catster magazine.
If you have an aging cat, odds are about one in three that your cat might one day suffer from chronic kidney disease. According to the Banfield Pet Hospital’s annual State of Pet Health Report, the incidence of the disease in cats has increased 15 percent from 2007 to 2011. And in 2014, one in every 10 geriatric cats (10 years or older) had kidney disease.
“I have no doubt that many cats go undiagnosed and suffer without their owners having any idea,” said Dr. Kate Pietsch, a veterinarian in Dartmouth, Massachusetts.
Supporting her notion, the banfield survey demonstrated that at least three in five cat owners are unaware that diarrhea, vomiting, lethargy, and weight loss can be associated with the illness.
What’s more, cats — who are skilled at masking illness — don’t exhibit symptoms until there is significant kidney damage. In fact, because of limitations of blood tests (and the urinalysis) used to diagnose chronic kidney disease – detection doesn’t occur until about 75 percent of kidney function is destroyed.
People have long desired a way to detect chronic kidney disease earlier, and now it has happened.
A new sensitive test, called symmetric dimethylarginine or SDMA — is offered with the IdEXX regular blood chemistry panel. SDMA determines kidney disease much sooner in its progression, when there is only about a 40 percent loss of function.
“A cat can live a completely normal life with about 50 percent of kidney function,” Pietsch said. “We believe these cats still feel great, while that’s not the case for cats diagnosed with a 75 percent loss of function.”
Pietsch is among the legion of veterinarians who call the test a “game changer.” but now what? After all, there’s no medication that stops kidney disease in its tracks. The Winn Feline Foundation is funding studies to better understand whether stem cell therapy can help, and some researchers are attempting to determine exactly why so many older cats get the disease in the first place. but those answers will take some time to find.

So, in the meantime, how do veterinarians treat this early diagnosis? They are attempting to figure this out.
Finding kidney disease early in cats is like diagnosing high blood pressure or high cholesterol in people. Doctors know of the irregularity and hope to see patients more frequently so they can track any changes as well as suggest lifestyle changes. The same holds true for when chronic kidney disease is found in cats.
For example, when the SDMA test indicates kidney changes, Pietch said, “Encourage cats to stay hydrated; encouraging more water can do no harm. Some cats like running water provided by a drinking fountain for cats. Depending on the cat, I may advise a moist food diet (which contains more water than kibble).”
She said such changes might slow the disease.
“We’re discovering loss of kidney function (determined by SDMA) in lots of middle aged cats before the cat becomes sick. This is extremely important to potentially slow the disease progression and help us to monitor kidney loss.”
Cats with changes in kidney function or chronic kidney disease should visit the veterinarian at least twice a year. Without the SDMA test showing kidney changes, most of these cats might not have visited again until the cat became ill, for whatever reason. Preventive care matters, and the additional visits not only allow vets to track kidney changes but also find other disorders such as dental disease or heart murmur, which the owner could never detect. Veterinarians can’t examine pets they don’t see.
Could SDMA saves lives?
“I’m sure the test already has,” Pietsch said.