Dog proteinuria: definition, origins and diagnosis

What is proteinuria?

Proteinuria refers to the presence of protein in the dog's urine.

Proteins are valuable constituents for the body, so the kidneys have an important role to play in preventing them from being eliminated in the urine. When everything is working well, the kidneys normally prevent the passage of proteins from the blood to the urine. In a he althy animal, only trace amounts of protein should be found in the urine.

But, it sometimes happens that the kidneys do not fulfill their role correctly and that we find proteins, and more precisely albumin as well as globulins, in the dog's urine.The veterinarian usually realizes this during a urine analysis using a urine dipstick.

What can cause proteinuria in dogs?

In dogs, proteinuria can be secondary to:

  • a stress,
  • hyperthermia,
  • intense effort,
  • hyperproteinemia,
  • hemoglobinemia,
  • myoglobinemia,
  • glomerulonephritis,
  • a parasitic or vector-borne disease such as heartworm, leishmaniasis, borreliosis or even ehrlichiosis,
  • an infectious disease (endocarditis, sepsis, urinary tract infection)
  • systemic lupus erythematosus,
  • a tumor disease,
  • amyloidosis,
  • high blood pressure,
  • diabetes mellitus,
  • a disorder of the renal tubules,
  • a Fanconi syndrome,
  • urinary stones (or urolithiasis)
  • etc.

You will therefore have understood that proteinuria has various and varied origins, benign as well as more worrying.

What happens in case of proteinemia?

If your veterinarian detects the presence of protein in your pet's urine, he will carry out further investigations to locate the origin of this proteinuria. It can be pre-renal, renal or post-renal, and can be considered physiological or pathological.

One of the tests to determine the origin and severity of the problem is the protein to creatinine ratio in the urine. A protein/creatinine ratio that remains permanently high (significantly greater than 2) is a reliable indicator of proteinuria of renal origin and directs the veterinarian towards glomerulonephritis or amyloidosis.

Additional tests are sometimes necessary and may include blood tests, imaging tests, further urine tests and possibly a kidney biopsy.

The treatment of proteinuria obviously depends on the underlying cause, which will be identified by the veterinarian.