What is kidney/ renal failure in dogs?
The inability of the kidneys to remove waste products from the blood is kidney failure. 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. Kidney (renal) failure occurs when a dog’s kidneys are no longer able to remove waste and concentrate urine. The build-up of toxins produces the signs and symptoms of poisoning – called uremic poisoning.
Kidney failure can appear suddenly (acute kidney failure) or come on gradually over months (chronic kidney failure).
Healthy kidneys 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 and he begins to show signs of illness or poisoning.
NOTE: However these signs will now show until 75 percent of functioning kidney tissue is destroyed. Thus, a considerable amount of damage occurs before the signs are noticed. It is critical to check for renal failure at the first signs of change in urination behaviour of the dog.
Detection/ Signs of Kidney Failure
One of the first things you should notice is if the dog drinks and urinates more often. Its a cycle of more water intake to flush toxins and more urination causing subsequent dehydration and thirst.
As kidney function declines and urine can’t be concentrated the dog retains ammonia, nitrogen, acids, and other chemical wastes in her blood and tissues. The degree of uremia is determined by measuring serum blood urea nitrogen (BUN), creatinine, and electrolytes. This stage is called uremia.
Initial signs of uremia:
Apathy and depression
Loss of appetite and weight
Dogs at this stage now urinate less than normal
Ulcers may be present in the mouth.
An ammonia like odor to the breath – best way to detect is smell the mouth or press a finger to the gums and smell the finger
Signs of advance uremia
As renal failure progresses it may cause edema – typically retention of water in the limbs & abdomen
Vomiting, diarrhea, and gastrointestinal bleeding
At the end stages of kidney failure, the dog will have continuous seizures and falls into a coma
What should you do if you suspect kidney failure?
If you detect excessive drinking of water/ thirst in the dog and unusually high urination and/or loss of weight immediately get a blood test done. Kidney failure shows prominently in the blood chemistry as toxin levels (creatinine and nitrogen) rise.
Causes of kidney failure
Causes of acute kidney failure include:
Tick fever & other bacterial/ viral infections especially in blood
Rupture of the bladder or urethra
Shock, with inadequate blood flow to the kidneys
Congestive heart failure with low blood pressure and reduced blood flow to the kidneys
Acute failure and but mild enough may be completely reversible.
Causes of chronic kidney failure include:
Chronic renal failure is one of the most common diseases seen in older dogs, along-with with arthritis and cancer. 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. So be very sensitive to urination habits in older dogs. Chronic failure is caused by Nephritis or Nephrosis.
Nephritis is inflammation of the kidneys and is most often caused by auto-immune disorders that affect the major organs but may also be caused by infections & toxins.
Nephrosis is any degenerative disease of the renal tubules and will severely compromise renal function
For chronic renal failure, there is no cure – the focus is on disease management for the rest of life.
Treating Kidney Failure
Tests and monitoring
Dogs with kidney failure require periodic monitoring (once a month) of blood chemistry to detect changes in kidney function that may require medical intervention.
Restrict salt intake – this helps prevent/ delay edemand hypertension.
Protein is poorly metabolised by dogs with kidney failure and increases kidney load. Its best to put the dog on a renal diet. Dogs with weak kidneys can be thrown into uremia by feeding them more protein than they can handle.
It is extremely important to provide fresh water at all times. The dog must be able to take in enough water to compensate for her large urine output. Some dogs will need occasional boosts to their fluid intake.
2 things need to be remembered – fluid therapy and that its all about management.
On detection of renal failure the No 1 priority is to give enough fluid to flush out as much of toxic accumulation as possible – and it works very well in acute kidney failure. Depending on the size and blood chemistry 3-6 bottles (300ml) of R/L may be given for the initial 5-7 days and continued thereafter.
Restricting phosphorus intake is the other priority. Medications to lower phosphorus levels are required along with dietary adjustments.
If the disease is the result of irreversible kidney tissue damage, in many cases renal function will stabilize for weeks, months or years at a time. And while the disease will progress and kidney function will continue to deteriorate, the dogs symptoms can be minimized with supportive treatment. After the initial fluid support dogs go into a treatment that includes
Azodyl/Ipakitine/Rubinal (proprietary drugs) + Renal food formulations
You may want to explore human grade renal medication to keep up kidney function - these includes supplements, nutrition, hormones to compensate for lost kidney function (this can be recommended to you if you request us)
Blood transfusions to supply fresh blood that they dog may need. This has to be done carefully since new blood may itself increase kidney load but may be an best option in critical stages.
While some vets debate the efficacy of this treatment for at least 70% of the dogs in our care that were already critical we’ve been able to arrest symptoms for anything upto 6 months or more and give the dog a quality of life in this period.
Prevention of Kidney Failure
Many situations of acute renal failure can be prevented by ensuring dogs are kept safely away from toxic substances, heavy metals, rat poison and other pesticides, common household medicines
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.
Limiting drugs that 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.