A dog with kidney failure is a result of previous kidney disease. Kidney failure is the most severe case of kidney disease that can affect dogs.
What is dog kidney disease?
A dog with kidney failure is the consequence of kidney disease.
Knowing what kidney disease is and how it progresses to kidney failure is essential.
Several conditions external to the kidney can negatively affect kidney function.
The primary function of a dog kidney is filtering blood from toxic substances, mainly urea, resulting in urine production. Kidney disease is any condition affecting the kidney’s functional parts (parenchyma) or the primary culprit for kidney disease.
In technical jargon, kidney disease is any anatomic or functional lesions in one or both kidneys, irrespective of the extent or, in summary, kidney malfunction.
Is kidney disease common in dogs?
The percentage of dogs with kidney disease is not so large, but the affected dogs will have a hard time if we don’t give them the proper medical care and love.
Up to nearly 4 % of the dog population at risk suffers from kidney disease. The dogs more at risk are senior dogs. About 80% of dogs with kidney disease are senior dogs.
The mortality rate is about 60%, which means 40% of dogs may survive and have a typical lifespan for dogs with the proper management of the disease.
The main risk factor besides advanced age is the breed. This means that some dog breeds are, according to researchers, at higher risk for kidney disease:
- Cocker Spaniels
- Cavalier King Charles Spaniel
- Bernese mountain dog
- Miniature schnauzer
From these, the Bernese mountain dog does not seem to tolerate the disease well and, unfortunately, has a higher mortality rate than the other breeds at risk.
How does kidney disease develop in dogs?
The kidney has three main functions:
- Detoxifying the body: eliminating hazardous substances like urea through blood filtration to produce urine
- Regulating the level of acidity (pH) of the blood
- Producing some hormones that affect other parts of the dog’s body
The kidney is, therefore, a vital organ.
When dogs have kidney disease, all the three mentioned functions are affected.
Urea, the primary toxic substance the kidney filters, accumulates in the bloodstream and wreaks havoc on many organs (like the liver and the brain) when the kidneys are not working well. As a result, the blood becomes more acidic (a condition called metabolic acidosis).
Also, the kidney stops producing some hormones, the most remarkable being erythropoietin, which stimulates the bone marrow to produce red blood cells. Therefore, dogs with kidney disease may develop anemia (low red blood counts). Some blood-pressure-controlling hormones also stop being produced in the kidney.
Ultimately, urea builds up in the blood, creating a crisis that can be fatal for dogs if untreated.
Dog kidney disease develops in stages. Dog kidney disease stages are four, 1 to 4, from the least to the most severe (see the symptoms and signs section).
What are the kinds of kidney disease in dogs?
There are basically two kinds of kidney disease in dogs acute and chronic.
Anything damaging the functional tissues of the kidney may cause one of these two variants of the disease.
- Acute kidney injury (AKI) happens fast and is potentially reversible.
- Chronic kidney disease (CKD) develops gradually over time and is irreversible. Kidney disease is considered chronic when it’s been ongoing for at least three months.
According to the location within the organ, kidney disease in dogs can be of two types:
Glomerulonephritis is the inflammation of the filtering units (glomeruli) located near the surface of the kidney (cortex).
Pyelonephritis is the inflammation of the microscopic urine-carrying tubules in the kidneys’ central part (medulla).
You don’t need to know these technicalities, but your Veterinarian will need to know what’s happening with precision to think of the best option for your dog.
A specialist in dog kidney disease is called a veterinary nephrologist or urologist.
What are the causes of kidney disease in dogs?
Acute (fast onset) kidney injury originates mainly from toxicity to ingested chemicals, for example, some antibiotics, painkillers (NSAIDs), tainted food, and commonly, antifreeze and other products containing ethylene glycol.
Chronic (long-term) kidney disease in dogs comes mainly from unknown causes (idiopathic) but also from some infections caused by bacteria (like Leptospira or dental bacteria that travel to the kidneys and other organs like the heart), genetic (familial renal disease) in some dog breeds (examples: English Cocker Spaniels, West Highland White Terriers, Boxers, Bull Terriers, and Shar Pei) or progression from acute kidney injury.
Sometimes kidney disease is caused by cancer.
Your Veterinarian will work out the best possible strategy to treat these types of kidney diseases.
What are the main dog kidney disease symptoms and signs?
The following signs may indicate kidney disease in dogs.
What owners usually see is:
- Dogs show a lack of appetite
- Lethargy (sleepiness)
- Vomiting and/or diarrhea
The following symptoms are also present, but many owners fail to notice them:
- An increase in the volume of urination (lots of pee)
- An increase in the volume and frequency of water drinking (your dog drinks lots of water very often)
- Pain when touched in the back
- Pallor of the mucous membranes (for example, the mouth’s inner mucous parts and the eye conjunctiva may appear very pale)
Pain in the back occurs because that’s where the ill kidneys are located. Exactly where are the dogs’ kidneys located?
Technically, in the sublumbar region (the dogs’ back), see the Image below to know where the dog kidneys are placed.
The pallor of the mucous membranes occurs because, besides producing urine, the kidneys make a hormone that helps produce blood red cells by the bone marrow (erythropoietin). The resulting condition of low counts of red blood cells is called anemia.
Other clinical signs that may be present include:
- Halitosis (bad breath)
- Weight loss (because dogs eat less)
- Hair loss (caused mainly because of loss of appetite that will lead to some degree of malnutrition or nutrient deficiencies)
- Dog lick their paws or mouth often
- Tremors or shakes (spasmodic muscle twitching in some muscles)*
- Cramps (painful)*
- Seizures (generalized tremors)*
*Tremors, cramps, and even seizures are caused by low calcium levels in the blood (related to kidney malfunctioning). Don’t be tempted to give your dog calcium supplements without a veterinarian’s supervision. You may cause the opposite condition, hypercalcemia, which can also lead to serious health problems for your dog.
Dogs with kidney disease usually have cardiac conditions.
It is very important to notice the onset of the disease and provide this information to the veterinary surgeon. That is, if the signs start suddenly or gradually. This information is relevant because it will indicate the course of the treatment. Remember that acute kidney injury is curable, while chronic kidney disease is irreversible, and dogs will have to live with it for the rest of their lives.
Some worries, like a dog with kidney disease that won’t eat and other unsettling symptoms, will get better after the dog starts proper treatment.
What are the basic dog kidney blood test results?
In the next section, you will see the basic values for creatinine, a compound found in high amounts in blood when the kidneys are not working well.
The earlier a dog is diagnosed with kidney disease, the best and faster your Veterinarian will be able to react and design an appropriate plan of treatment.
The earliest this diagnosis can be made is at stage 1 using a Cys-C (Cystatin C) test. It is highly accurate and sensible enough to detect kidney disease when symptoms are absent or not observable.
Progression and aggravation of signs
Can kidney disease in dogs be infectious?
Rarely some microorganisms cause dog kidney disease and could be infectious. Among bacteria that cause kidney disease in dogs are those from the genera Leptospira which is transmitted by contact with the urine of the affected animal. In addition, Ehrlichia canis, responsible for the infection called ehrlichiosis in dogs, transmissible through tick bites, can sometimes produce kidney malfunction.
Also, bacteria entering the urinary system via the urethra can arrive in the bladder and continue to travel to a dog’s kidneys through the ureters. An example of this bacteria is Escherichia coli. Bacteria reach the female dog kidneys more easily than the males’.
What is the treatment for dog kidney disease?
Your vet will first treat any underlying cause of kidney disease, such as infectious, inflammatory, or neoplastic (cancer) conditions.
If anemia is severe, your vet may use drugs like the missing erythropoietin or other bone marrow stimulants. In extreme cases of anemia, vets will recommend blood transfusions.
As kidney-produced blood-pressure-related hormones are affected, dogs may be treated with hypertension drugs (dogs with kidney disease will have sodium retention, among other derangements that cause high blood pressure).
Your vet will probably prescribe renal diets, low in phosphorus, protein, and sodium and rich in omega-3 fatty acids (to reduce inflammation), to your dog (more about this below).
Your Veterinarian may also prescribe immunosuppressive drugs for immune-mediated kidney disease (a disease in which the body’s immune system attacks the own dog’s kidney).
In acute kidney injury, your Veterinarian will help you identify the offending poison or toxicant your dog may have swallowed and instruct you to avoid ingestion or access to it.
Some medications used in dog kidney disease
These are some of the medications your Veterinarian may prescribe for your dog when suffering from kidney disease. Here are some of the usual ones so that you have some idea:
- Appetite stimulants
- Antiemetics (when vomit is present)
- Antihypertensive (the kidneys’ natural antihypertensive hormones are not being made when malfunctioning)
- Antiproteinuric medications (proteinuria is when the kidneys leak proteins into the urine, which they should not be doing)
- Acid-reducing medications (examples: Famotidine; Omeprazole)
- Phosphate binders (given with food, will bind to excess phosphate in food and avoid their absorption in the bowel)
- Erythropoietic medication (the kidneys’ made natural erythropoietic or blood cell-making hormones are not being produced when they are malfunctioning)
- Antithrombotic medication (recommended to reduce hypercoagulability or blood clot formation associated with proteinuria)
Dog with kidney disease diet: some recommendations
So what can a dog with kidney disease eat?
Probably the best food for dog kidney disease is a veterinary therapeutic renal diet or renal support diet
Diet phosphorus is the most critical nutrient of concern for dogs with kidney disease. Phosphorus is an element with elevated blood values in dogs with kidney disease.
Decreasing dietary phosphorus intake is an essential strategy that slows the progression of the disease and increases the dog’s lifespan.
During dog kidney disease, calcium blood levels increase (causing tremors), a condition called hypercalcemia. To control this, your vet or animal nutritionist will attempt to manipulate the calcium-to-phosphorus ratio.
Protein in prescription diets for dog kidney disease is higher to avoid weight deterioration due mainly to rapid muscle loss. Your vet will probably recommend a diet with normal amounts of protein in case of proteinuria (protein leakage into the urine) due to glomerulonephritis (see above for explanation).
What supplementation or diet incorporating vitamins and minerals should be considered for a dog with kidney disease?
Since blood tends to become acid during kidney disease, alkalinizing agents are recommended, such as sodium bicarbonate
Since potassium levels drop in blood, dogs with kidney disease are sometimes given potassium gluconate, or potassium citrate (the latter also an alkalinizing agent to counteract blood acidosis)
Calcitriol (an active form of vitamin D). Under normal conditions, the dog kidney transforms vitamin D from dietary supplements or sun-activated to the active form of vitamin D. During chronic kidney disease, low vitamin D levels can be expected to decrease severely. For that reason, the active form of vitamin D is administered to dogs with kidney disease.
Vitamins C and E act as antioxidants that may reduce renal oxidative stress.
Fish oil provides omega-3 fatty acid supplementation with eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) for their anti-inflammatory properties.
Summary of renal (kidney) diets for dogs:
- Low in phosphorus
- Higher in protein to avoid weight loss
- Protein shouldn’t be raised in case of proteinuria (glomerulonephritis)
What about homemade food for dogs with kidney disease?
Many recipes in books and on the Internet do not provide a complete balanced nutrition appropriate for kidney disease. A veterinary board-certified veterinary nutritionist or a veterinary urologist should prescribe homemade diets for pets with kidney disease. Once you get the directions on how to make your own dogs’ kidney-balanced food at home, follow the instructions strictly to avoid any nutritional deficiencies or kidney toxicities.
For general information on consultations on veterinary nutrition, we encourage you to visit these pages:
Things a dog with kidney disease should and shouldn’t eat
Here are some answers to people’s questions about specific foodstuffs for dogs with kidney disease.
Should dogs with kidney disease eat potassium-rich foods like sweet potatoes or bananas?
Potassium depletion occurs during long-course (chronic) kidney disease mainly because animals do not feel like eating and don’t get that much potassium from the diet. Also, they are losing it through the urine. In that case, your vet will advise on whether your dog should be supplemented with potassium or given sources of natural potassium like bananas and potatoes. These natural foods will contain enough potassium but also calories. Energy in the form of calories will be considered by your Veterinarian when revising your dog’s diet. Another condition to consider by your vet is that some dogs may have elevated potassium concentrations. In that case, food with high potassium content should be avoided.
Can dogs with kidney disease eat salmon?
Dogs with kidney disease can eat salmon and other fish with skin.
This is because salmon will be accepted by many dogs with anorexia (unwilling to eat). Besides, salmon and other fish with skin contain omega-3 fatty acids, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA), which are good for the kidneys and overall health of your dog.
Foods to avoid when a dog has kidney disease
There are several foods to avoid when your dog has kidney disease.
Here are some examples:
- Dairy products (they are high in phosphorus, which will tend to be already high in dogs with kidney disease)
- Peanut butter. Avoid it, mainly because it is very fatty. Fats release free radicals that may produce further damage to an ill kidney. Besides, peanut butter tends to be too salty, i.e., too high in sodium, which is unsuitable for a dog with kidney disease
- Human food scraps (for several reasons, usually over-salty)
How much water should a dog with kidney disease drink?
As we mentioned above, an excess of thirst and high-volume urination are some of the dogs’ earliest signs of kidney disease.
Dogs may drink high amounts of water because the kidneys fail to concentrate the urine during kidney disease. Under such circumstances, the body compensates by stimulating the mechanism of thirst. For this reason, you must provide your dog with an unlimited supply of fresh water. Tap water is ok.
As the disease advances, dogs may become nauseous. This nausea may result in decreased appetite, less thirst, and possibly even vomiting. If at the nauseous stage, provided your dog tolerates it, offer cold water (adding some ice cubes to the bowl containing water). Cool water will soothe the stomach mucous membrane and reduce the possibility of vomiting.
How to prevent kidney disease in dogs?
Prevention should be specific to the specific cause of kidney disease:
- Carefully monitor your dog for any kidney disease signs when previously getting treatment with drugs known to harm the kidneys (like some antibiotics or NSAIDs). Your Veterinarian should inform you about this when prescribing such medications.
- Keep antifreeze, drugs, rodenticides, or any substances potentially hazardous for the kidney away from the reach of your pets
- Keep your dog vaccinations up to date (leptospirosis produces kidney infections)
- Brush your dog’s teeth regularly (recommended: three times per week) and visit your Veterinarian for teeth cleaning (prophylaxis) once a year.
- Provide and make available fresh, clean water to your dog
Be aware of breeds susceptible to kidney disease (examples: English Cocker Spaniels, West Highland White Terriers, Boxers, Bull Terriers, and Shar Pei). Since these dogs are more prone to have kidney disease, be alert to notice any kidney disease signs as early as possible.
What is kidney failure in dogs?
Kidney failure is a condition that occurs when the kidneys cannot keep their blood cleansing, body regulation, and endocrine functions. Renal failure occurs when 75% or more of the nephrons are not working (a nephron is the smallest individual kidney filtering unit, the kidney has thousands of these in the cortex, near the surface).
A dog with kidney failure has a limited lifespan (about eight months on average). Your Veterinarian will give you indications to give your dog the best possible quality of life during this period. With proper care, dog kidney disease life expectancy can be extended considerably.
Kidney failure is one of the most common natural death causes in senior dogs.
How does kidney disease turn into kidney failure?
Renal failure is a progression of kidney disease. In some cases, acute kidney injury can quickly become kidney failure (like in ethylene glycol poisoning or excess consumption of kidney-damaging drugs).
In dogs with chronic kidney disease, kidney failure is a matter of time, and we can only delay the onset with the appropriate treatment and good general life quality.
Chart: dog kidney failure stages
What are the signs of kidney failure in dogs?
Signs are the same as in previous kidney disease stages, but more severe:
- Considerable weight loss
- Vomiting, often with digested blood (brown particles)
- Severe lack of appetite
- Movements are awkward (as if drunk)
- Pale gums (may even bleed)
- Odd breath smell (chemical-like)
- Changes in water consumption
- Changes in urine volume; can go to zero
When kidney failure worsens, digested blood may be present in the stool, making it look very dark. This happens because toxins build and cause the gut to be sluggish, producing constipation and bleeding.
The dog may become depressed and, as the condition progress, enter into a coma before dying.
Is dog kidney failure painful?
When dog kidney disease is inflammatory, dogs will feel some pain when you touch or make some gentle pressure in the lumbar (back) area (where kidneys lie below)
May kidney failure in dogs be treated?
Kidney failure will require admission to a veterinary hospital Intensive care unit. The mortality rate of kidney failure is high if not caught on time.
Treatment consists of vital support, intravenous fluids to rehydrate the dog, specific kidney medications, and sometimes antibiotics.
Dog kidney transplant
The procedure of dog kidney transplant is complicated in dogs. The immune system of dogs usually rejects the new kidneys and tends to have surgical complications. The cost can be near 20,000 $
How do you prevent kidney failure in dogs?
By following a veterinarian-tailored treatment, the proper diet (see above), and an enriched dog environment, we aim to avoid advancing from kidney disease stages (1 through 3) to stage 4 (kidney failure). Kidneys are vital organs, and dogs depend on them for a healthy life.