Jack Russell dog

A dog with a kidney infection may need to urinate more.

© Shutterstock

Kidney infection in dogs

By Dr. Katy Ellison MA VetMB MRCVS Veterinarian

Updated on the

A dog with a kidney infection may have a fever and an increased need for drinking and urinating. Despite this, it may only take a few days to get them back to normal.

The kidneys are the organs responsible for filtering the blood and excreting waste products in the form of urine. If they stop functioning as they should, very quickly toxins will build up in the bloodstream and the dog will feel very unwell. One of the more common causes of kidney disease in dogs is infection. The kidneys have a hugely important function, so if an infection develops what are the consequences and how do we treat it?

What are the symptoms of kidney infection in dogs?

The clinical signs or symptoms of kidney infection (pyelonephritis) are varied but tend to include lethargy, fever, an increase in thirst and urination, and frequently blood in the urine (haematuria). Very often there will be pain in the region of the kidneys that will be apparent when the dog’s abdomen is palpated, together with pain on urination.

What are the causes of kidney infection in dogs?

Kidney infections usually result from a bacterial infection that starts in the lower urinary tract. In these circumstances the infection is described as an ascending infection because it spreads from the bladder up the ureters to the kidneys. In many cases there is no obvious reason why the infection started, but there are various factors than can predispose a dog to developing both lower urinary and upper urinary tract infections, and these predisposing factors should be investigated at an early stage. Routine blood tests are advisable to rule out conditions such as diabetes mellitus and Cushing’s disease, both of which increase the risk of urinary tract infections (UTIs). X-rays or scans are useful for ruling out bladder or kidney stones as an underlying cause, as well as checking for a number of congenital conditions.

What treatments are there for kidney infection in dogs?

The treatment of kidney infections will almost always require the use of antibiotics. This should always be based on the results of what is known as culture and sensitivity testing of urine, to make sure the right antibiotic is used for the particular bacteria involved. This is important to help reduce the rise of antibiotic resistance through the use of inappropriate antibiotics. Antibiotics will normally be continued for at least two weeks, but can be up to six weeks in some cases. Repeat culture and sensitivity testing after the antibiotic course has finished is advisable to make sure that the infection has cleared up completely. Intravenous fluids may be necessary to support kidney function, especially if your dog is feeling very unwell and off their food.

What can I give my dog for a kidney infection?

There is nothing that you can give your dog that will treat a kidney infection. In almost every case antibiotics will be required. In the worst case scenario, kidney infections can cause permanent damage to the kidneys, resulting in kidney failure, As such, do not delay making an appointment with a veterinary surgeon.

How can I treat my dog’s kidney infection naturally?

It is never advisable to try to treat your dog’s kidney infection naturally. Not only are any natural treatments unlikely to work, but you actually risk causing your dog harm through delaying starting effective treatment. If you suspect that your dog may have a kidney infection, always contact a veterinary surgery as soon as possible.

Can dogs recover from kidney infections?

Most dogs will recover uneventfully from a kidney infection. But it is important that any potential underlying cause for the infection is investigated to reduce the risk of the infection recurring.

How long does it take for a dog to get over a kidney infection?

Most dogs will start to feel much better within a few days of starting antibiotics, but full recovery can take a bit longer. Importantly, a dog may seem back to normal well before the bacteria have been fully cleared from their kidneys, so a course of antibiotics must be completed even if the dog seems fine long before the medication is due to finish. The infection cannot be confirmed as fully cleared until a negative urine bacterial culture has been obtained. In some cases this may require up to six weeks of antibiotics.

How does a vet diagnose a kidney infection in a dog?

The first step in diagnosing a kidney infection will be culture of a urine sample for bacteria. Ideally this should be collected by a procedure known as cystocentesis, which is when a fine needle is inserted into the bladder using an ultrasound scan to guide the procedure. This may sound uncomfortable, but it is the only way to obtain a sterile sample. If what are known as “free catch” samples (a sample collected into a pot when your dog urinates) are used, there is risk of contamination of the sample by bacteria that are present in the environment. Mild sedation is sometimes used for cystocentesis.

Blood biochemistry tests to check kidney function as well as haematology to look for evidence of infection (specifically a rise in numbers of white blood cells) may be advised alongside urine tests. It can still be tricky to determine that the infection is within the kidneys rather than the lower urinary tract, but by putting all test results together, along with the findings from a thorough examination, a diagnosis can usually be reached.

How do you know when a UTI becomes a kidney infection in a dog?

If a urinary tract infection (UTI) becomes a kidney infection, it will make your dog feel very unwell. They are likely to be very subdued, will exhibit signs of pain associated with their kidneys and may have a high temperature  They will probably have a reduced appetite and may vomit. In contrast a simple UTI involving the bladder will largely cause signs of urinary discomfort, such as straining to urinate (dysuria) and passing frequent tiny volumes of urine.

What is the difference between a bladder infection and a kidney infection in a dog?

Bladder and kidney infections are both urinary tract infections. The bladder and urethra make up the lower urinary tract, and the kidney and ureters make up the upper urinary tract. Most UTIs start in the bladder and the main signs will be discomfort when urinating and passing small amounts of urine very frequently. Occasionally the infection will ascend to the kidneys and, when this happens, the dog will tend to feel much sicker than if the bladder alone is involved. They may have a temperature and their kidneys will be painful. Kidney infections are potentially more serious than bladder infections because they can result in kidney failure.

What are the symptoms of bladder and kidney infection in a dog?

The typical signs shown by a dog with a bladder infection are straining to pass urine (dysuria), frequent passing of small amounts of urine and blood in the urine (haematuria). Bladder infections do not tend to make dogs feels particularly unwell. By contrast, dogs with a kidney infection will feel unwell with a high temperature, poor appetite and pain associated with their kidneys, in addition to dysuria, increased frequency and haematuria.

Are there home treatments for a dog kidney infection?

There are no home treatments that are effective at treating kidney infections in dogs. It is not worth risking your dog’s health by attempting a home remedy, as it will almost certainly be ineffective. Serious complications can arise from kidney infections that are not treated promptly, including irreversible kidney failure.

How do you know if your dog has a kidney infection?

Dogs with a kidney infection will seem unwell. They may have a temperature, be off their food and seem thirsty. You may notice traces of blood in their urine and an increase in the frequency with which they need to urinate, resulting in urinary accidents in the house. If your dog is bouncing around the house wagging its tail and pestering you for a walk, they are unlikely to have a kidney infection.

What can I give my dog for a urinary tract infection?

It is not advisable to treat a urinary tract infection (UTI) yourself. A bladder infection tends to cause significant discomfort when the dog urinates, so delaying proper veterinary treatment is not fair on your dog. Additionally, if a bladder infection is left untreated, it may spread to the kidneys. The consequences of delaying treatment, if the infection involves the kidneys, are more serious and can include permanent kidney damage that will have long-term consequences for your dog. It is never appropriate to try to medicate your dog for a UTI without seeking veterinary advice.

When should I see a vet?

If you suspect that your dog may have a kidney infection, you should contact a veterinary surgeon without delay. So if your dog is showing signs of discomfort when they pass urine, has blood in their urine, are drinking more than normal and are off their food, contact a veterinary surgeon at the earliest opportunity.

More advice on...

What did you think of this advice article?

Thanks for your feedback !

Thanks for your feedback !

1 person found this advice article helpful.

Leave a comment
Connect to comment
Want to share this article?