We speak of renal failure in dogs when the kidney of dogs no longer functions normally and does not perform or not efficiently enough its mission of filtering blood and forming urine.

In the dog’s body there are two kidneys which act as a filter by eliminating certain toxins, such as urea which is a waste of the metabolism of proteins, ions and minerals, proteins and water. It also prevents the outflow of sugar and other elements from the blood by reabsorbing them. This game of elimination and reabsorption by the kidney serves as a filter but also as a regulator of several balances in the body: acid-base and mineral balances, osmotic pressure (which is the distribution of solid bodies in the organism) or quantity of water around the cells of the body. Finally, the kidney secretes hormones to modulate blood pressure.

When the kidneys do not work and filter poorly or no longer filter, it is said that there is kidney failure in the affected dog. There are two types of kidney failure. Chronic renal failure (CKD) is progressive, the kidneys work less and less well, and eventually no longer function sufficiently to ensure the survival of the dog. Acute kidney disease (AKI) comes on suddenly, and can be reversible, allowing the kidney to function normally again.

Kidney failure in dogs can occur, for example, as a result of:

• The presence of bacteria in the blood (following a skin infection for example) or in the urinary tract can induce an infection and inflammation of the kidneys called nephritis or glomerulonephritis.
• An infectious disease such as dog leptospirosis Lyme disease.
• An obstruction to the exit of urine by the natural routes by a calculus or an oversized prostate in the uncastrated male dog
• Poisoning the dog with a toxicant such as antifreeze ethylene glycol, mercury, anti-inflammatory drugs intended for humans, or grapes and other plants
• A birth defect (dog born with only one kidney or defective kidneys)
• An inherited disease such as Bernese Mountain Glomerulonephritis, Bull Terrier nephritis or Basenji glycosuria.
• A trauma during a violent impact directly on the kidney during a road accident with a car for example.
• A side effect of drugs such as some antibiotics, some anti-cancer chemotherapy drugs, some anti-inflammatory drugs
• An autoimmune disease like Lupus.

The symptoms of kidney failure are many and varied:

• Increased water intake. The presence of kidney failure in dogs dehydrates them and makes them feel permanently thirsty. Even if your dog drinks a lot, he can still be dehydrated if his kidney is malfunctioning.
• Increased urine elimination. As he drinks a lot, the dog also begins to urinate a lot, it is called polyuropolydipsia (PUPD). Sometimes we can confuse this important elimination of urine with incontinence because the dog has trouble holding back so much his bladder is full.
• Appearance of vomiting which is not necessarily related to the meal. Urea in dogs creates gastric acidity and causes gastritis.
• Occurrence of diarrhea with blood sometimes.
• Anorexia or decreased appetite. Stomach acidity, the presence of toxins in the blood, pain, fever or imbalances in the blood can suppress a dog’s appetite.
• Weight loss, muscle wasting. Anorexia and excessive protein excretion in the urine causes the dog to lose weight.
• Abdominal pain. Some causes of dog kidney failure can cause severe pain in the stomach.
• Presence of blood in the urine

Kidney failure in dogs is characterized by many symptoms of sudden onset (ARI) or progressive (CRS) that are not very specific. However, the appearance of polyuropolydipsia (increased thirst and the amount of urine) is often a warning symptom and should lead the dog to a veterinarian to find the cause of this symptom.

PUPD should alert you to your dog’s state of health. A healthy dog ​​drinks about 50 ml of water per pound per day. When this value exceeds 100 ml of water per kilo per day there is surely a problem. Associated with this PUPD can appear frequent digestive disorders or urinary symptoms.

Your veterinarian will do a blood test and in particular he will check the level of urea in the blood (uremia) and the level of creatinine in the blood (creatinine). These two markers are used to assess the severity of kidney failure. He may combine this blood test with a urine test with:

• a measurement of urine density, a dog with impaired kidney function will have very dilute urine and the urine density value will be low.
• a urine test strip that can detect proteins, blood, sugar and other abnormal elements in the urine.
• a urine pellet observed under a microscope to find the cause of the dog’s renal failure, bacteria, urinary crystals, immunity cells, urinary tract cells …
• an abdominal ultrasound or x-ray can also be done to see if kidney damage or urinary tract obstruction may be responsible for kidney failure in dogs.

Finally, a kidney biopsy can be done in order to observe the state of health of the kidney and to give a precise idea of ​​the cause in case of congenital malformation for example or the prognosis of cure.

If the cause of the dog’s kidney failure is found, your vet will prescribe medication to treat it (such as an anti-biotic) or surgery to remove the stones.

In the case of acute renal failure the emergency treatment will consist of infusing the dog, injecting diuretics and treatments for digestive disorders.

In the event of chronic renal failure your dog will receive drugs intended to slow the progression of the disease and delay the onset of its consequences, as well as an adapted diet. Your dog will need to be monitored very regularly by your veterinarian. Older dogs should be especially supervised.