Kidney Disease: The Silent Killer



The second leading cause of nonaccidental death in cats and dogs, kidney disease is truly a sneaky killer. It can be months or even years before symptoms surface, and the disease is diagnosed. By then, the damage may be severe and irreversible.

"There's no cure for kidney disease in cats and dogs--yet," says Arnold Plotnick, DVM, a veterinarian board certified in both internal medicine and feline medicine and surgery who operates Manhattan Cat Specialists, a full-service, feline-only facility in New York City. "But owners, working closely with their veterinarians, can detect this disease earlier and slow its progression."

Here's what to do.

Get your (kidney) facts straight. Your pet's two kidneys filter out toxic waste. They produce renin, a key hormone that helps control blood pressure. They regulate potassium, phosphorus, calcium, and other electrolytes, substances that play a variety of important roles in the body. And they help stimulate bone marrow to produce red blood cells. But when they're out of whack, they cannot effectively filter harmful toxins.

Treat urinary tract infections (UTIs) without delay. "An undetected or ignored UTI can lead to a kidney infection and, subsequently, kidney failure," Dr. Plobnick says. "If you notice blood in your dog's or cat's urine, or if your pet is straining to urinate or making repeated trips to the litter box or fire hydrant and only urinating a drop or two, see your vet," he advises. Antibiotics can clear up a UTI before the infection spreads to the kidneys.

Watch the food and water bowls. If the water bowl is emptying faster than usual, if your pet is leaving food in his bowl, or both, you should see your vet. Increased thirst and loss of appetite can be early signs that his kidneys are ailing. Meanwhile, take steps to keep him hydrated, since kidney failure can lead to dehydration. Refill water bowls more often. If your pet eats dry food, mix in some water or broth, or switch to canned food, which contains more moisture than the dry stuff.

Monitor your pet's activity level and weight. If your once-frisky feline or dash-about dog has taken to dozing the day away, or if he's started losing weight, ask your vet for a full exam. Lassitude and weight loss can also be warning signs of kidney trouble.

Schedule regular kidney screening tests. Chronic kidney disease affects more middle-aged and senior pets than young ones. Once your pet hits middle age (7 or 8), get blood and urine tests to screen for kidney disease. Depending on the results, it may be prudent to repeat these tests annually, so your vet can monitor levels of toxins such as blood urea nitrogen and creatinine. Elevated readings of these toxins can signify kidney damage.
Life Extension

Pets with chronic kidney disease fare much better today than they did just a few years ago, thanks to the development of special diets and greater success with kidney transplants.

Switching your pet to a prescription diet that's lower in protein and phosphorus appears to make pets more comfortable, and it slows the progression of the disease. Pets with renal failure that are fed these types of diets live longer than those fed a regular diet.

Excessive dietary protein forces the kidneys to filter a bit harder than normal, causing more wear and tear. A lower protein level in the diet helps relieve some of the strain on the kidneys. While healthy kidneys remove excess phosphorus from the blood, diseased kidneys aren't able to do this as well. "Excess phosphorus can team up with calcium to form calcium phosphate, a mineral that can form crystals in the kidneys and speed the rate of kidney failure," Dr. Plotnick explains. A few major commercial pet product companies make kidney-friendly prescription diets. Ask your vet for a prescription for file one he prefers.
Not for Everyone

Kidney transplants for dogs are relatively rare. They are somewhat more common in cats, with greater success reported. The ideal transplant candidate is an animal whose only health problem is kidney disease, says Lillian Aronson, VMD, director of the feline kidney transplant program at the University of Pennsylvania's College of Veterinary Medicine in Philadelphia. She adds that age is not much of a factor. About 70% of the cats that receive transplants through her program are still alive at least 1 year later. The survival rate for dogs averages about 40%.

A kidney transplant from a healthy donor animal takes about 4 to 6 hours and costs about $7,500. Like people, animals can live with just one kidney, so the donor keeps one, and file other goes to the ailing cat or dog. The owner of an animal receiving a kidney must agree to adopt the animal donating the organ, Dr. Aronson notes.

Methods of detecting kidney disease earlier would make a tremendous difference in prognoses. Greg Grauer, DVM, and Lisa Moore, DVM, professors in the department of clinical sciences at Kansas State University in Manhattan, have uncovered evidence that pets with early-stage kidney disease may have abnormal levels of a protein called albumin in their urine. If so, a urine test measuring albumin levels could be used to diagnose the disease early on, when it is most responsive to treatment.

As diagnostics exist today, about 75% of kidney function has been lost by the time a diagnosis is made, and therefore treatment options are relatively limited. "Early detection is the best way to manage this disease," says Dr. Grauer.
Warning Signs

Call your veterinarian if your cat or dog shows any of these warning signs of kidney disease:

* Excessive urination
* Increased thirst
* Nausea
* Vomiting
* Dehydration
* Lethargy
* Oral ulcers
* Muscle atrophy
* Poor hair coat
* Loss of appetite

QUICK TIP: Keep your pet out of the garage. If swallowed, antifreeze can damage kidneys.

PHOTO (COLOR): Just say no to high-pro.

PHOTO (COLOR): Too pooped to play?


By Arden Moore

Pet expert Arden Moore is the award-winning author of The Kitten Owner's Manual (Storey Books, 2001) and Dog Training: A Lifelong Guide (BowTie Press, 2002) and the editor of Catnip magazine. She is a graduate of The Humane Society of the United States's "Pets for Life" national companion-animal training program.

Share this with your friends