kidney failure in dogs lab values
Kidney Disease in Dogs: Signs, Symptoms, and Treatment
Your dogs kidneys are essential organs that filter waste products from the bloodstream. When the kidneys are weakened, either by acute or chronic kidney disease, your dogs health could suffer. Because kidney disease progresses over time, its important to learn the common symptoms so tha you can recognize them. If you catch kidney disease in dogs early on, treatment can slow down the progression and allow your dog to live longer.
What Is Kidney Disease in Dogs?
Kidney disease in dogs is sometimes called renal or kidney insufficiency because it occurs when a dogs kidneys stop doing their job as efficiently as they should. The main job of the kidneys is to help clear and excrete waste products from the blood and convert them to urine, says Dr. Jerry Klein, Chief Veterinary Officer for the AKC. If the kidneys are not working properly, these waste products can build up in the blood, causing detrimental effects.
Dogs can get either acute kidney disease, which develops suddenly, or chronic kidney disease (CKD), which develops slowly and worsens over an extended period. Both involve loss of kidney function, but they result from different circumstances. Acute kidney disease is a sudden attack or injury to the kidney, whereas chronic kidney disease is a slow, degenerative loss of kidney function, Dr. Klein explains.
What Causes Kidney Disease in Dogs?
Dr. Klein warns that kidney disease could be caused by a lot of things, including infection (such as with the bacteria that causes leptospirosis), trauma, genetics, drugs, toxins, cancer, mechanical obstructions (like kidney stones), and degenerative diseases (where the job and form of the affected body part get worse over time). Anything that decreases blood flow to the kidneys, such as dehydration or heatstroke, can cause the kidneys to fail.
Acute kidney disease in dogs can be caused by exposure to hazardous materials, including toxic plants such as lilies, certain drugs, harmful foods such as grapes or raisins, or antifreeze. Puppy-proofing your home and yard can keep your dog away from potentially harmful items or foods that could be toxic.
Chronic kidney disease in dogs is also associated with growing older. Because kidney tissue cant regenerate once its damaged, the kidneys can wear out over time. As small-breed dogs often live longer than large-breed dogs, they tend to show early signs of kidney disease at an older age10 years old or more, compared to as young as 7 for the large breeds.
What Are the Symptoms of Kidney Disease in Dogs?
The earliest signs of kidney disease in dogs are increased urination and therefore increased thirst. Other symptoms dont usually become apparent until about two-thirds of the kidney tissue is destroyed. So, in the case of CKD, the damage may have begun months or even years before the owner notices. Because of this, its common for the signs of kidney disease in dogs to seem like they came out of the blue when in fact, the kidneys have been struggling for a long time.
Other signs of chronic kidney disease in dogs to watch for include:
Dr. Klein says there are some rarer symptoms of kidney disease in dogs to be aware of, as well. On occasion, there can be abdominal painurinary obstructions or stonesand in certain instances, one can see ulcers in the oral or gastric cavity. In extreme cases, little or no urine is produced at all.
What Are the Stages of Chronic Kidney Disease in Dogs?
Kidney disease in dogs is measured in stages. Many veterinarians use the IRIS scale, which has four stages. Blood work measurements like creatinine and SDMA (biomarkers for kidney function) allow your vet to assign your dog to a particular stage which will determine the exact treatment.
Dr. Klein explains, The stages determine how well the kidneys can filter waste and extra fluid from the blood. As the stages go up, the kidney function worsens. In the early stages of CKD, the kidneys are still able to filter out waste from the blood. In the latter stages, the kidneys must work harder to filter the blood and in late stages may stop working altogether.
How Is Kidney Disease in Dogs Treated?
Dialysis (a medical procedure that removes waste products and extra fluid from the blood) is far more common in humans than in dogs, although peritoneal (kidney) dialysis can be performed in some cases. On rare occasions, surgical kidney transplant is possible in dogs.
But Dr. Klein specifies that depending on the type and stage of kidney disease, the main treatments for CKD are diet changes and administration of fluids, either directly into the veins (intravenous) or under the skin (subcutaneous). The balancing and correction of electrolytes are extremely important in the management of kidney patients, he explains.
Proper nutrition is needed, and there are many available diets formulated for cats and dogs with kidney issues, some by prescription only. Your veterinarian can help guide you to the most appropriate diet for your pet.
Because kidney disease, particularly in the late stages, can cause a dog to lose their appetite, it can be difficult to encourage your dog to eat enough. Dr. Klein advises, There are medications used as appetite stimulators available, such as the prescription drug mirtazapine. Capromorelin has recently been FDA-approved for dogs to address appetite in chronic kidney disease.
When Do You Need to Call Your Vet?
The prognosis and expected life span for a dog with kidney disease depend on the type of disease, the speed of progression, and underlying conditions present in the dog. However, the more serious the disease, the poorer the outcome. Thats why its so crucial to catch the illness early on.
According to Dr. Klein, In chronic kidney disease, there are methods, such as diets and medications, that can be used to lessen the burden of work the kidneys need to do and may help slow down the progression from one stage to the next. In acute kidney disease, there is less time and fewer choices available to prevent further damage to the kidneys and to try to jump-start the kidneys to get them to function normally.
Regular veterinary exams, including bloodwork, are an excellent way to spot kidney problems before the outward symptoms become apparent. And if you notice any of the above signs, dont hesitate to get your dog to the vet for further testing. It can make a huge difference in preserving kidney function and your dogs well-being for as long as possible.
Kidney Failure in Dogs
What Is Kidney Failure in Dogs?
The primary job of the kidneys is to filter the blood by removing waste products and controlling the amount of fluid and nutrients kept in the body and how much is passed in urine.
With any type of kidney failure, this filtering isnt working well, so waste products are not properly removed from the bloodstream and too much fluid is passed in urine along with proteins and electrolytes. As waste products build up in the blood and tissues, dogs can get ulcerations (tears) in the lining of their digestive tract as well.
Kidney failure may also be referred to by terms listed below. The word renal refers to all things related to kidneys, and is often used interchangeably. Failure, insufficiency, and disease are commonly used to describe similar issues with the kidneys.
Kidney disease is often divided into categories based on how long it has been affecting the dog. Acute renal failure occurs in a very short time frame, and is often caused by eating or drinking a toxin or getting a severe infection that harms the kidneys. Chronic kidney disease refers to a process with a more gradual onset or one that has been happening for a longer period of time.
Changes that can occur with an aging pet are often caused by chronic kidney disease, but if a dogs kidneys were damaged by eating a toxic item several months ago and he now has renal failure because of this, it is also known as chronic kidney disease.
Symptoms of Kidney Failure in Dogs
Drinking more water (polydipsia)
More frequent urination (polyuria)
Urinary accidents in house-trained pets
Lack of energy
Refusing to eat
Vomiting
Drooling
Changes in defecation (either diarrhea or constipation)
Weight loss
Mouth sores
Bad breath
Weakness
Causes of Kidney Failure in Dogs
Kidney failure can occur because of an acute event, such as a toxin ingestion or infection that harms the kidneys; degenerative (worsening) changes over time; or an underlying medical condition that damages renal tissues, which can occur due to genetic predispositions in some dog breeds.
Specific causes include:
Ingested toxins
Metabolic diseases
Kidney infections
Autoimmune disease
Cancers
Breeds that are prone to inherited renal failure include:
How Veterinarians Diagnose Kidney Failure in Dogs
Your veterinarian will want to run several tests, in addition to a physical exam, to diagnose kidney failure, such as:
Complete blood count
Chemistry panel
Urinalysis with culture
Abdominal ultrasound
Treatment of Kidney Failure in Dogs
Treatment of kidney failure is based on the severity of the disease and whether it is acute or chronic.
Acute kidney disease is treated with hospitalization and IV fluid therapy to support the kidneys and help them remove wastes. Depending on the cause of the disease, decontamination medications, toxin-binding medications, antibiotics, or medications to support the gastrointestinal tract may be given. In extreme cases, renal dialysis can help the kidneys. This last procedure is rare, only available at some university or veterinary specialty hospitals.
Chronic kidney disease requires careful management of dogs at home. They need to have access to water at all times and be encouraged to drink water. Many dogs have improvements with a prescription kidney diet. Some dogs need to be on medications to control high blood pressure or to protect their stomach. Pets with chronic kidney disease need to see their veterinarian often so that their renal values can be checked. Some dogs with kidney disease need to receive injectable fluids at home or may even need to be hospitalized at times to help their fluid needs.
Recovery and Management of Kidney Failure in Dogs
With acute kidney failure, prognosis is variable depending upon the cause of the disease, how severe the disease is, how damaged the kidneys are, the speed and aggressiveness of treatment, and the dogs response.
For chronic renal failure, long-term prognosis is not good. Most dogs die or are euthanized within a year because of poor quality of life.
The families of dogs with kidney disease should expect to watch them closely and will need to see their veterinarian often, especially as their pets kidney function gets worse. These dogs will be easily dehydrated, as their kidneys are not able to keep water in their bodies. Any infection, vomiting, diarrhea, or changes in appetite or activity could severely dehydrate the pet and worsen the disease.
Kidney Failure in Dogs FAQs
How does kidney failure differ from kidney disease?
Kidney disease is a broader term that includes any problem with the kidneys. Kidney failure is a specific term that means the kidneys cant keep up with filtering waste products and managing fluid levels.
Is kidney failure fatal in dogs?
Depending on the severity and progression of the disease, kidney failure can be fatal.
WRITTEN BY
Laura Russell, DVM, MBA, DABVPVeterinarian
Dr. Russell is a 2003 graduate of the University of Missouri. She is board certified in Canine and Feline Practice, certified in canine...
What Do Kidney Numbers Mean in Dogs?
If you have been refilling your dogs water bowl more frequently and letting him outside more often to relieve himself, then a visit to the veterinarian is in order. These can be symptoms of kidney disease, Cushings disease or diabetes. The first thing your veterinarian will do is collect blood and urine samples for testing. If the diagnosis is kidney disease, several key values exist in the test results that your vet will watch for.
Urine Specific Gravity and Albumin
Kidneys that function normally remove waste from the bloodstream to be expelled in urine while retaining as much water in the body as possible to maintain hydration. The result is concentrated urine. Poor kidney function cannot concentrate the urine, which is why your dog must drink more water in an attempt to excrete the excess toxin load. This leads to dilute urine. Your veterinarian is interested in the urine specific gravity to determine how efficiently the kidneys are concentrating your dogs urine. The normal specific gravity range for a dog is 1.015 to 1.050. A lower specific gravity value indicates poor kidney function. The other urine value to observe is the albumin level. This represents the level of blood proteins that have leaked from the deteriorating kidneys into the urine. The normal range is 2.7 to 4.4, and a higher value indicates kidney disease.
Blood Urea Nitrogen and Creatinine
Two key kidney values in your dogs blood chemistry are the blood urea nitrogen and the creatinine levels. Blood urea nitrogen and creatinine are both metabolic protein wastes that the kidneys filter from the blood. When the kidneys can no longer keep up with their filtration duties, the levels of these wastes rise. A normal blood urea nitrogen range for dogs is 6 to 25, and the normal range for creatinine is 0.5 and 1.6. Higher values indicate failing kidney function. When the creatinine level nears 5.0, you dog will feel sick and may show such symptoms as vomiting, fatigue and decreased appetite. At this stage, 80 to 90 percent of his kidneys have been destroyed.
Blood Phosphorus and Potassium
Phosphorus, a mineral component found in the blood, works in tandem with your dogs calcium to maintain strong bones. Too much phosphorus creates an imbalance of the two minerals, so the kidneys must excrete just enough phosphorus to maintain a healthy phosphorus-to-calcium ratio. A normal phosphorus level is 2.8 to 6.2. When your dogs phosphorus value exceeds this range, his bones will start to weaken. Potassium is an important mineral and electrolyte responsible for maintaining your dogs heart function and overall well being. The ideal range is 3.6 to 5.5. In early stage kidney disease, potassium levels tend to be elevated, resulting in a condition called hyperkalemia. In the advanced stage, the potassium level falls dangerously low, resulting in hypokalemia.
Values Must Be Tracked
When your veterinarian has confirmed a diagnosis of kidney disease, he will discuss treatment options. To place less stress on the wearing kidneys, your veterinarian may prescribe a diet that is low in protein, sodium and phosphorus. He might prescribe medications to help maintain your dogs present values, and suggest fluid therapy to help keep your dog hydrated. Your vet will run periodic blood chemistry panels and urinalyses to track the kidney values so adjustments in treatment may be made to address any changes as they arise. He may also monitor your dogs blood pressure, which can elevate as a result of kidney disease. Kidney disease is a degenerative condition, meaning that there is no cure. The goal of treatment is to slow the progression of the disease and preserve your companions quality of life for as long as possible.
