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Pyelonephritis in Dogs

Pyelonephritis in dogs can be serious.

Pyelonephritis in dogs is a bacterial infection of the kidneys and ureters, which are the tubes that carry urine from the kidneys to the bladder. This is an upper urinary tract infection.

Pyelonephritis is not the same as a bladder infection, which usually refers to a lower urinary tract infection, or UTI. UTI is a bacterial infection of the bladder and urethra, which is the tube from the bladder to the outside world.

What Causes Canine Pyelonephritis?

Usually, pyelonephritis is the result of a bacterial infection in the lower urinary tract moving up into the kidneys and ureters. These infections may start when bacteria from stool or other outside contamination like the dog's mouth, secondary to licking at the vulva or penis, ascend the urethra and colonize the bladder.

Sometimes an abnormality in the way a dog's urinary tract is formed can lead to increased instances of pyelonephritis. Also, certain medical conditions like Diabetes in Dogs increase the risk of lower urinary tract infections and, by extension, pyelonephritis.

Leptospirosis is a bacterial infection that dogs get from infected wild animals, and it commonly causes pyelonephritis. You can learn more about this condition, which is transmissible to humans, here: "Leptospirosis in Dogs."

What Are the Signs of Pyelonephritis in Dogs?

Dogs with pyelonephritis may not show any signs of illness. Some dogs, however, may have signs consistent with a lower urinary tract infection, including:

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Dogs with infections that have moved into the kidneys may show these additional signs:

  • Lethargy
  • Decreased appetite
  • Fever
  • Vomiting
  • Pain when the abdomen near the kidneys is palpated

How Is Canine Pyelonephritis Diagnosed?

Infection of the urinary tract can be diagnosed with a urinalysis and/or urine culture, which is a lab test that grows any bacteria present in a urine sample on a petri dish so it can be identified. However, this does not tell the veterinarian that the infection is specifically in the kidneys.

An ultrasound might show abnormal kidney size and character which, along with urine culture results, can indicate kidney involvement. Sometimes, a fluid sample from inside the kidney, taken with a needle during an ultrasound or during an exploratory surgery, is necessary to diagnose kidney infection. Veterinarians often presumptively diagnose the condition based on urine culture results and physical exam findings.

Treatment of Pyelonephritis in Dogs

Treatment of kidney infection in dogs requires aggressive antibiotic therapy. The antibiotic used is chosen based on the results of a urine culture and sensitivity test, but sometimes a veterinarian will need to start a broad spectrum antibiotic while waiting for those test results.

Some dogs need hospitalization and intravenous fluids and medications if they are not eating, are vomiting, and have become dehydrated. Depending on the cause of the urinary tract infection and pyelonephritis, further treatment might be necessary to reduce the risk of recurrence.

You May Also Like These Articles:

Urinary Tract Infection: UTI in Dogs

Causes of Frequent Urination and Urinary Accidents in Dogs

One Simple Test Your Dog Needs Every Year

Urine Marking in Dogs

Leptospirosis in Dogs

Kidney Disease in Dogs

Cleaning Dog Urine

How to Get Dog Urine out of Carpet


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