Canine Chronic Renal Disease

It can’t be cured but it can be managed—partnering with your vet is the key.
By Sara Greenslit DVM, July 2015

Failure is a harsh word. It signifies loss of hope, or defeat. So when your vet diagnoses your dog with chronic kidney failure, how can your heart not sink? That’s why some DVMs call it chronic renal insufficiency (CRI) or chronic kidney disease (CRD) instead.

Maybe you made a vet appointment because your dog spends more time at the water bowl, seems overly thin and shies away from previously loved food. Some pets with kidney disease may also have urinary incontinence, vomiting, diarrhea, bad breath, blindness, depression or lethargy—all of which may be signs that the kidneys’ multitasking capacity is impaired.

These two bean-shaped organs are responsible for water conservation, blood pressure control, salt balance, phosphorus and calcium regulation, and the initial step in red blood cell production. When their performance of these jobs begins to falter, many of the body’s functions start to tumble too. Blood levels of BUN (blood urea nitrogen), creatinine, calcium and phosphate escalate; protein spills into the urine; potassium levels fall; red blood cell counts drop; and blood pressure rises. Your dog starts to feel very unwell, indeed.

Where to Start

CRD affects one in ten dogs (compared to one in three cats), and the initial medical goals are to investigate and address an inciting cause in an effort to halt the disease. The origins of CRD are many: chronic bacterial infections, kidney stones, immune-mediated diseases, high blood pressure, congenital kidney malformations, leptospirosis, Lyme disease, grape/raisin or antifreeze poisoning, cancer. Often, we don’t find the specific reason. We also want to attend to the dog’s clinical signs—dehydration, nausea, weight loss, fatigue—with treatments fine-tuned by test results. If the dog’s getting nephrotoxic drugs like NSAIDs and certain antibiotics, we’ll take him off them too.

CRD is managed, not cured, and your vet will refine her treatment plan by regular monitoring of your dog’s health. Tests recommended every three months might involve a renal panel (CBC and chemistries), urinalysis, urine culture, urine protein/creatinine ratio and blood pressure.

The first signs of CRD—elevations in BUN and creatinine levels—typically occur when the kidneys have lost 75 percent of their function, which has made its treatment challenging. However, Idexx Laboratories now offers a blood test, SDMA (symmetric dimethylarginine), which catches CRD at the 40 percent mark and allows earlier intervention.

Allopathic Treatment

Treatment goals for CRD are life-long and supportive, aimed at improving quality of life and slowing disease progression. Since the kidneys perform numerous functions, various medications are used to address specific disorders. ACE (angiotensin-converting-enzyme)–inhibitors are prescribed for hypertension and/or urine protein loss, antacids like famotidine or omeprazole for GI ulcers and overly acidic stomach, maropitant and metoclopramide for nausea. When indicated, phosphate binders reduce nausea, and potassium supplements boost low levels.

Your veterinary team can teach you how to give subcutaneous fluids at home, if needed, to hydrate your dog and flush out toxins. You can also encourage your canine friend to increase his water intake by providing a pet water fountain, adding wet food to his diet, and placing clean bowls with fresh water in multiple rooms. Your vet will also likely suggest a diet change. Prescription diets like Hill’s K/D, Royal Canin Renal MP and LP, Iams Renal Plus, and Purina N/F restrict phosphorus and sodium, reduce protein and add omega-3 fatty acids with B and C vitamins, a combination that has been tested to increase lifespan and overall quality of life. Restricting protein too early, however, can lead to muscle wasting. IRIS, the International Renal Interest Society, endorses a kidney-specific diet when a dog’s creatinine level rises to 2.1 to 5 mg/dl (Stage III). You can also find online support for home-cooked CRD diets via veterinary prescription (see info box). To make it more likely that your dog will accept a new diet, make the switch slowly.

Integrative Options

The body does not store water-soluble B-complex and C vitamins, so we need to replace them every day. When dogs have CRD, these essential nutrients wash out too easily with the dilute urine. Prescription foods compensate for these expected losses, and Renal Essentials by Vetriscience, a highly palatable and balanced supplement with vitamins, potassium, fish oil and herbs, can be given twice daily as well.

Studies document that high daily doses of oral omega-3 fatty acids enhance the function of joints, heart, skin, brain and kidneys. In one study, fish oils decreased mortality, improved renal function and diminished protein loss. The recommended dose of marine fish oil, omega-3 EPA and DHA, is 300 mg per 10 pounds of dog weight. Do not use cod liver oil, as it may have excessive A and D vitamins.

In the Manual of Natural Veterinary Medicine, Drs. Wynn and Marsden advocate traditional Chinese herbs for CRD, based on clinical experience. Studies in rats showed that Liu Wei Di Huang/Rehmannia 6 enhanced renal blood flow. Wynn and Marsden have also seen cats thrive for years when started in early-stage CRD on Shen Qi Wan/Rehmannia 8, another important formula. Rehmannia 8, with cinnamon and aconite, is warming, and this combination, when consistently used, can lower BUN and creatinine levels, reduce vomiting and thirst, boost appetite and weight, decrease urine volume, and increase urine concentration. Consultation with a TCVM vet is highly recommended for beginning and monitoring pets on Chinese herbs.

Rounding out a holistic kidney care plan, consider chiropractic to release spinal fixations and improve hind-end weakness that are common with CRD, and acupuncture to enhance the TCVM herbs’ effectiveness.

We who love dogs want our companions to live long and happy lives. If your canine has CRD, you can approach the disease from an integrative approach, maintaining quality of life and slowing kidney degeneration. Optimizing our dogs’ health may involve monitoring and close management, but they repay us with their company and more days of infinite joy.

Sara Greenslit, DVM, CVA, is a small-animal  veterinarian and writer who lives and practices  in Madison, Wisc.