Just as they do for humans, your dog’s kidneys serve many important functions, including the removal of toxic and waste products from her blood. If your dog is drinking lots of water and urinating much more than usual, her kidneys may not be doing their job properly.
Kidney failure, also known as renal failure, is accompanied by an illness called uremia. It can be either acute (sudden) or occur over time (chronic), which is most often the case. It is common in senior dogs, and some breeds are prone to be born with conditions leading up to it.
What are the Symptoms of Kidney Failure?
Unfortunately, according to pets.webmd.com, “Dogs with kidney failure do not show signs of uremia until 75 percent of functioning kidney tissue is destroyed. Thus, a considerable amount of damage occurs before the signs are noticed.”
One of the first signs you may notice is your dog’s frequent drinking of water. According to petmd.com, “Increased toxins and other metabolic waste products triggers sensors in the brain that the blood is too concentrated, and through a series of chemical reactions the animal may have a sense of dehydration. Your dog, in turn, drinks more water to alleviate this sensation.”
Because your dog is drinking so much water – and because her kidneys are not concentrating her urine as they normally would – she will probably be urinating a lot more than usual.
“This results in a large urine output over which the dog has no control, with subsequent dehydration and thirst,” notes MedicineNet.com. The urine will be thinner due to the inability of your dog’s kidneys to remove toxin and waste products from her body.
As the condition worsens, your dog may show these additional symptoms, according to MedicineNet.com and petmd.com:
- Apathy and depression
- Loss of appetite and weight
- Dry coat
- Brownish discoloration on the surface of her tongue
- Ammonia-like breath odor
- Less frequent urination
- Mouth ulcers
- Edema (swelling caused by accumulated fluids in her tissues)
- Gastrointestinal bleeding
In the final stage, your dog will become comatose.
What Causes Kidney Failure?
When the kidneys’ tiny filtration units, called nephrons, fail to regenerate, kidney failure will occur.
“Nephrons can be destroyed quickly or slowly,” writes marvistavet.com. “Usually, by the time less than 1/6 of our original nephrons are left, whatever the inciting disease process was is long gone and there is no way to tell what happened. All we can do is make the kidney workload easier by making up for the kidney’s inadequate performance with medication or supplements. Hopefully, we can also slow the progression of the failure.”
Dogs may be born with problems such as kidneys that are missing, malformed or that do not fully develop. Among the breeds more prone to hereditary kidney problems are Basenjis, Bernese Mountain Dogs, Bull Terriers and German Shepherds.
Although kidney cancer is very rare in dogs, other types of cancer can spread to the kidneys and damage them. “There is also a form of leukemia in dogs that targets the kidneys and crowds out normal kidney cells,” notes petmd.com.
Another cause is the ingestion of poisons. “One of the most devastating external toxins that causes kidney failure in dogs is antifreeze that contains ethylene glycol,” writes petmd.com. Some other items you might have around your house that can damage your dog’s kidneys should she eat them include grapes and raisins; Easter lilies; vitamin D; thallium; turpentine; and lead, mercury and other heavy metals.
How is Kidney Failure Diagnosed?
The two main ways of diagnosing kidney failure are by testing your dog’s urine and blood.
Your vet will take a urine sample and check its urine specific gravity measurement (SpG) to see how diluted the urine is. Normal dogs have an SpG of 1.020 to 1.040, while the range for dogs with kidney failure is 1.008 to 1.012. There may also be sugar, protein, bacteria or blood in the urine, which rarely appears in that of normal dogs.
A sample of your dog’s blood will also be drawn to check the levels of blood urea nitrogen (BUN) and creatinine. Petmd.com notes that while BUN levels in normal dogs are rarely higher than 25 to 30 mg/dl (milligrams of material per 100 milliliters of blood), many dogs with kidney failure may have a level of 90 or even higher.
How is Kidney Failure Treated?
“Dogs with kidney failure require periodic monitoring of blood chemistries to detect changes in kidney function that may require medical intervention,” writes MedicineNet.com.
If your dog is suffering from kidney failure, it is very important to reduce her salt intake and provide plenty of fresh water. Less salt in her diet “helps prevent edema, ascites [accumulated fluids in the abnominal area] and hypertension,” according to MedicineNet.com.
Water is important to compensate for your dog’s frequent urine output. “Some dogs will need occasional boosts to their fluid intake,” MedicineNet.com notes. “This can be done by giving subcutaneous (known as sub-Q or SQ) fluids. With most dogs, their owners can learn how to do this at home. In the later stages of kidney failure, dogs may need sub-Q fluids daily.”
Dialysis, a process that duplicates the filtering function performed by the kidneys, is rarely used on dogs because it is expensive and time consuming. The procedure is also stressful for dogs.
In very extreme cases, a kidney transplant may be performed.
“The goal of treatment is to allow the patient to live as close to a normal life as possible under the circumstances,” writes petmd.com. Supplements containing reishi mushroom help detoxify the kidneys and protect kidney tubule cells from oxidant damage that leads to kidney failure, thus helping to improve the quality of life for dogs dealing with kidney disease.
Find A Vet HOW TO articles are intended for informational purposes only. You should always consult with your veterinarian about any health issues affecting your dog.
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