By Dr. Becker
Kidney (renal) failure occurs when a dog’s kidneys are no longer able to remove waste and concentrate urine. The bodies of animals produce toxins all day, everyday, and the toxins circulate to the kidneys to be dissolved in water, filtered out and excreted through urination.
A healthy kidney makes highly concentrated urine, meaning a large amount of toxins can be handled and excreted in a relatively small amount of water.
A failing kidney, by contrast, needs more and more water to excrete the same amount of toxins. A dog in kidney failure will drink increasing quantities of water, until eventually he simply can’t drink enough and toxin levels in his bloodstream begin to rise.
There are two types of kidney failure: acute and chronic.
Acute renal failure (ARF) comes on suddenly and can be caused by:
- Ingestion of a poison like antifreeze, a medication meant for humans, or the Easter Lily plant
- An overwhelming bacterial infection
- Dehydration, usually because the dog is left without easy access to fresh drinking water
- Decreased blood flow to the kidneys – a situation that can occur, for example, during a surgical procedure, or as a result of heat stroke, or where there is heart disease
- Urinary obstruction
Chronic Renal Failure (CRF) is a slower process and develops over months or even years. It is most common in older dogs.
Acute kidney failure can be turned around in some cases; in others, it can become chronic. Unfortunately, the majority of chronic kidney disease is irreversible.
Acute Renal Failure Signs and Symptoms
When kidney failure is acute, symptoms come on quickly and are often severe. The top three to watch for are:
- Complete loss of appetite
- Marked lethargy
Other symptoms you might notice:
- Straining to urinate and decreased urine production
- Physical weakness; loss of coordination
ARF is a very serious, life-threatening situation and fast action is required if there is to be any hope of saving your dog’s life.
There’s No Time to Waste If Your Pet is in Acute Renal Failure
If you notice any of the symptoms listed above, or if you know or even suspect your pup has ingested a poison or is suffering the effects of heat exposure or dehydration, call your vet or an animal emergency clinic immediately and prepare to transport her there.
If the diagnosis is ARF, your pet will be hospitalized for intensive treatment. If she survives the initial crisis, and unfortunately many pups don’t, her chances for full recovery of kidney function will depend on how badly the organs are damaged, the underlying cause of the condition, and the treatment she receives.
The goal of treatment for ARF is to provide supportive care while the kidneys recover. It can take anywhere from several days to a few weeks to determine whether an ARF dog will bounce back, and to what extent.
Urine output is a very important indicator for recovery. If a pup continues to have low or no urine output as treatment progresses, sadly, the prognosis is very poor.
If conservative treatment isn’t moving a dog’s health forward, there may be other options, for example dialysis or organ transplant. Decisions about whether to go ‘above and beyond’ will depend on the availability of such resources locally, and even more important, how the pet owner feels about more aggressive forms of treatment.
Chronic Kidney Failure (CRF)
Chronic renal failure is one of the most common diseases seen in older dogs, right up there with arthritis and cancer.
Unfortunately, by the time most dogs show signs of kidney disease, much of the irreplaceable tissue needed for good renal function is already destroyed.
Many pet owners mistakenly think that as long as their dog is peeing a lot – often more than he did in his younger years, in fact – his kidneys are still working well. In fact, the opposite is true.
A dog with developing kidney disease will feel the need to drink and urinate more in an effort to keep his body free of waste – a job his kidneys once did with a whole lot less effort. This cycle of over drinking and over urinating will work for a while, but eventually, no amount of water will be enough to get the job done.
By the time your pet starts showing other obvious signs of illness, for example lack of appetite, weight loss or low energy level, significant irreversible kidney damage has occurred.
Additional symptoms of CRF, which unfortunately are symptoms of many other conditions as well, include:
- Decreased or lack of urination
- Urinating during the night
- Bloody urine
- Vomiting and/or diarrhea
- Hunched posture; reluctance to move
- Poor coat condition
Chronic kidney disease can also cause:
- Mouth ulcers and bad breath from a buildup of toxins in the bloodstream
- High blood pressure, which can result in changes in the retina of the eyes
- Anemia as a result of decreased red blood cell production
- Smaller than normal, enlarged and/or or painful kidneys
- Fluid retention in the limbs and abdomen
If your pup’s CRF is caused by some factor other than damaged kidneys -- for example a disease that decreases blood flow to the kidneys or a urinary tract obstruction -- it’s possible the problem with the kidneys can be reversed with appropriate treatment of the underlying cause. That’s why it’s important for your vet to determine the source of the CRF.
If the disease is the result of irreversible kidney tissue damage, in many cases renal function will stabilize for weeks or even months at a time. And while the disease will progress and kidney function will continue to deteriorate, your pet’s symptoms can be minimized with supportive treatment.
Fluid therapy is a cornerstone of treatment for dogs with kidney failure, primarily to prevent dehydration due to the large amount of water that is passed out of the body.
Subcutaneous (under the skin) fluid delivery may be necessary, and many pet owners can do this at home after some instruction by their veterinarian. Potassium is often added to the fluids or the animal’s diet to safeguard against muscle weakness and heart rhythm disturbances that result from low electrolyte levels. In some cases, IV fluids may also be required.
Your dog should have round-the-clock access to fresh, clean water. Withholding water, for example overnight, will not solve your pet’s need to urinate in the middle of the night and could cause a real health crisis.
You’ll need to keep careful track of the amount of food and water your pet consumes each day. If consumption decreases, additional fluids must be administered to prevent dehydration. You should also weigh your pet at least weekly to insure she’s getting enough calories to maintain her weight and proper hydration.
The food you feed your dog with CRF is also critically important for disease management and overall well-being. A reduced amount of high-quality protein and high moisture content are essential, but phosphorus intake must be restricted. Since phosphorus is found primarily in high protein food sources, you can quickly see the need for expert guidance on how to best nourish your pet.
Your integrative/holistic vet is your best resource for advice on the right diet for your pet’s condition, and also what supplements, medications if necessary, and other therapies will help sustain your dog’s health and quality of life.
Kidney Failure Prevention
Not every cause of canine kidney failure is known or understood, nor can every case of ARF or CRF be prevented. However, there are a number of things within your control that can go a long way toward promoting the health and longevity of your precious pup’s vital kidney function.
• Many situations of acute renal failure can be prevented by ensuring dogs are kept safely away from toxic substances like antifreeze, heavy metals, rat poison and other pesticides, common household medicines, and certain foods and plants.
• Any dog with a bacterial infection, urinary obstruction or other illness that could lead to compromised kidney function should receive proper treatment, the sooner the better.
• Insuring your dog is never struck or kicked or gets out in a roadway will prevent possible trauma to her kidneys that could lead to renal failure.
• Limiting the drugs, vaccines and surgical procedures your pet is subjected to throughout her life will reduce the amount of toxins her liver and kidneys must process. Kidney failure in elderly dogs is usually the result of worn out organs. The less stress on your pet’s kidneys, the longer they’ll do their job effectively.
• Feeding a balanced, species-appropriate diet instead of commercial pet food will supply your dog’s body with the fundamental nutrition he requires for the health of every organ and system in his body, including his kidneys. Low quality, highly processed pet foods – in particular dry kibble, which lacks the moisture content and quality protein pets need -- are being linked to many of the degenerative diseases seen in pets today.
• Take note of even small changes in your pet’s behavior, appetite, thirst and energy level. Don’t assume increased thirst and urination is nothing to be concerned about. Trust your inner voice if it tells you to make an appointment with your holistic vet to discuss the state of your dog’s health.
With any degenerative condition there is opportunity while your pet is in the ‘gray zone’ between health and illness, to slow, halt or even reverse movement toward the black zone and full-blown disease.
• Perform regular at-home wellness exams and make sure your pup gets at least one and preferably two wellness visits with your holistic or integrative vet each year. This is the best way to stay on top of your pet’s health and address problems as they arise.