While kidney disease will not affect every senior dog, it’s a good idea to learn about any issue that can affect our pet’s health.
In this overview, we’ll learn what the terms associated with this disease mean, what the kidneys do and the two types of kidney failure.
Definitions
Chronic kidney disease (CKD), Chronic renal disease (CRD), Chronic renal failure, and Chronic renal insufficiency are all the same condition
*The kidneys are damaged but working, just not as well as they should be
*The disease has been present for months, maybe even years
*The onset may be very slow with no obvious signs, but your dog just isn’t feeling well
Kidney failure/Renal failure
*The most severe stage of CKD
Acute kidney injury (AKI), Acute kidney disease (AKD), Acute Kidney/Renal Failure (ARF)
*Kidney problems came on very quickly
The cause typically determines whether the disease is acute or chronic. More about that later.
What the Kidneys Do
• The kidneys filter waste from the blood, the waste is removed with water, and becomes urine.
• Waste is made up of broken food, old cells, toxins, poisons and drugs used for treatment of diseases.
• Some waste products like creatinine and urea nitrogen can be measured in the blood, but many can’t. My dog Red had kidney disease, and I know my vet was always monitoring those numbers, among other things.
• The kidneys regulate the amount of water in the blood by excreting the extra, or retaining some to prevent dehydration.
• They help control blood pressure by saving or eliminating sodium.
• They help regulate calcium and vitamin D.
• The kidneys manufacture a hormone that stimulates the bone marrow to produce new red blood cells.
• Sustain phosphorous levels.
Because the kidneys have so many functions, when the kidneys are not working normally, there are many signs you will see in your dog.
My dog Jack (in the picture above), sadly died from kidney disease last year March 2023.
Structure of the Kidneys
Each kidney contains thousands of nephrons. In a young dog, not all nephrons are working all the time – some are held in reserve.
As your dog ages or if the kidneys are damaged, some nephrons die and those in reserve take their place.
Eventually the reserve will be gone, so as the disease progresses that’s when your dog will start showing signs.
Because of the reserved nephrons, the kidneys are able to “hide” the fact they were damaged for quite some time – basically until the damage is severe.
By the time you’re noticing signs and tests are showing elevated creatinine in the blood, 75% of the nephrons in both kidneys have been lost.
There are Two Types of Kidney Disease – Chronic and Acute
Chronic kidney disease (CKD)
• Chronic kidney failure (or renal failure), does not mean the kidneys have stopped working and are no longer producing urine. As a matter of fact, most dogs in kidney failure produce huge amounts of urine.
• CKD means the kidneys are not able to efficiently filter the blood and rid the body of waste.
• It is caused by the gradual failure of the kidneys, or long term consequences of severe acute renal failure.
• This gradual process has been going on for months, or even years by the time your dog starts showing signs.
• CKD is progressive and irreversible, but can be managed with diet and medication. Dogs can be comfortable with a pretty good quality of life for months, even years.
Causes
• It is usually caused by aging
• A main cause is dental disease. Bacteria enter the blood stream, causing irreversible damage to the heart, liver and kidneys
• Birth defect
• Toxins
• Heredity
• Kidney stones
• Chronic bacterial infection of the kidneys
• Lymphoma
• High blood pressure
• Diseases associated with the immune system
• Polycystic kidney disease
• High blood calcium
• Urinary blockage
• Antifreeze poisoning causes acute kidney disease, which can lead to CKD
Most cases are idiopathic, meaning there’s no specific cause.
Signs
Because the kidneys perform so many functions, signs can vary, but some of the common ones include:
- Drinking and peeing a lot, and a need to pee during the night
- Vomiting
- Diarrhea
- Weight loss
- Not eating as well, more selective in what he/she eats
- General depression
- Pale Gums
- Mouth ulcers
- Poor looking coat
- Lethargy
- Dehydration
Prognosis
The prognosis depends on severity, but as we’ve already mentioned, this disease is irreversible and progressive.
It’s almost impossible to answer the question of “how long?” Your vet will monitor your dog’s progress on a regular basis, and it’s a case of playing it by ear.
My dog Red had this disease and was regularly monitored by her vet. She did ultimately die of kidney failure. This is her in the picture below.
Acute kidney disease (AKD)
Acute kidney failure is a sudden decline over a period of days.
When kidney function is reduced over a long period of time, it can become chronic.
Causes
• Trauma
• Medications
• Aspirin or ibuprofen
• Eating toxins like grapes, raisins or anti-freeze
• Bacterial infection in the kidneys due to blockage of the urinary tract due to stones/crystals
• Tainted foods
• Dehydration
• Heatstroke
• Bee stings
• Snake bites
• Leptospirosis (“bacterial disease of dogs and other mammals that primarily affects the liver or kidneys. The bacteria (Leptospira) that cause leptospirosis, commonly called leptospires, thrive in water”)
• Acute Pancreatitis
• Lyme Nephritis (a condition caused by Lyme Disease)
A definitive underlying cause, is often not found.
Before we talk about the signs, I wanted to discuss an incident that happened 3 days ago with my new 11 year old foster Milo. I had only had him a couple of days, when he ate 1 small chocolate covered raisin I dropped. I know chocolate and raisins are toxic to dogs, but I wondered if such a tiny piece could cause any problems. Like people everywhere looking for advice I turned to Google. I learned that some dogs are unaffected while others could suffer kidney damage from just 1 raisin. I also learned the treatment was to induce vomiting. I immediately called the shelter who recommended I call my vet and follow their advice. Within an hour I was at the vet, and poor Milo was throwing up. Interestingly enough it was the raisin that was the huge worry, not the chocolate. Thankfully he threw up the entire raisin intact right away. They then gave him charcoal to protect his stomach and prevent any further absorption. They recommend blood tests the next day to check if any damage had been done, although since it was only one raisin and it was not digested there really was no worry.
This is Milo in the picture below. He was obviously never taught any commands other than sit, so we’re working on “off.”
Signs
Dogs are usually diagnosed with acute kidney injury only once they are suffering acute renal failure, because it is then that signs are most obvious.
They include:
Peeing a lot, very little or having difficulty
Lethargy
Vomiting
Diarrhea
Abdominal pain
Drinking a lot, or drinking very little
Stomach or intestinal ulcers which cause black stool or vomiting of digested blood
Loss of appetite
Prevention
To prevent kidney problems due to poisoning, keep all dangerous and potentially dangerous products out of your dog’s reach. If you’re not sure, lock it up.
Never give your dog any medication unless it has been approved by your vet.
Keep an eye on her when she’s playing outside – dogs can pick up all kinds of things in a split second.
Prognosis
Sadly the prognosis isn’t great, with more than half of dogs put to sleep because they didn’t respond to treatment.
Even those that do recover may be left with chronic kidney disease.
Kidney Disease in Dogs – Conclusion
I hope this hasn’t overwhelmed you, or scared you. Even if you find out your dog does have kidney disease, each case is different so don’t panic.
Your vet will explain everything to you, prepare a treatment plan and closely monitor your dog, making adjustments as needed.
Remember, many dogs can continue to live good lives for months, or even years.
You know your dog best, so I always encourage anyone who notices changes in their dog’s behavior to speak to their vet. It may be nothing, or you may have just caught something in its’ early stages.
Does your dog have kidney disease? What were the signs you felt needed a vet check? What treatment did your vet recommend? Sharing helps others so please leave your comments below.
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I offer 1:1 support on everything from health & wellness advice and training tips, to preparing to say goodbye and grief counselling. You can find details on all the packages I offer by visiting the Senior Dog Care Support Service page. If you have any questions or would like to book your FREE 15 minute chat, please email hpearson141@gmail.com
I’ve been rescuing and caring for senior dogs since 2009. From vision and hearing loss to obesity, dementia, kidney disease, liver issues, cardiac problems, Cushing’s, mobility challenges and more, you could say I’ve dealt with and learned a lot! In addition to my hands on experience, I’ve taken many courses and earned several qualifications to keep learning how to help senior dogs and they include: Senior Dog Enrichment, Understanding Canine Anxiety, Care of the Senior Pet and I’m a Certified Pet Loss Specialist.