Blood in cat urine

Blood in Cat Urine (Hematuria)


Causes   Accompanying symptoms   Diagnosis   Treatment

Hematuria is the presence of red blood cells in the urine. It is a symptom of an underlying disorder and isn’t a disease in itself. As are many causes of hematuria in cats which can range from mild to severe and life-threatening, prompt veterinary attention is required.

It can be classified as microscopic or gross.

  • Microscopic hematuria is where the urine appears normal, but upon microscopic examination, red blood cells are found to be present.
  • Gross hematuria is where the cat’s urine is visibly discoloured due to the high numbers of red blood cells.



  • Trauma such as a car accident or a heavy fall
  • Blood clotting disorders such as hemophilia or thrombocytopenia
  • Polycythemia (increased red blood cells)
  • Certain medications
  • Idiopathic (no known cause)

Upper urinary tract – Kidneys and ureters

Lower urinary tract – Bladder and urethras

Accompanying symptoms

Hematuria may often be accompanied by other symptoms, some of which include:


The veterinarian will perform a physical examination and obtain a history.

Blood which is present only at the beginning of urination may suggest bleeding from the lower urinary tract, bleeding which is present at the end of urination may point to bleeding from the upper urinary tract and bleeding that is present throughout the urine is likely to originate from the kidneys, ureters or bladder. These can all help your veterinarian narrow down the cause of hematuria.

Diagnostic workup:

  • UrinalysisThe presence of white blood cells may indicate urinary tract infection. Protein in the urine may indicate kidney disease.
  • Complete blood count to check for anemia, white blood cells, red blood cell casts, and cancer cells.
  • Biochemical profile – A test of the clear portion of the blood to evaluate kidney function.
  • Abdominal ultrasound – To evaluate for stones, tumours, and kidney size.
  • Intravenous pyelogram (IVP) – This is a contrast x-ray examination of the kidneys, ureters, and bladder. The veterinarian injects contrast material into the patient and collects in the kidneys and urinary tract. This allows the veterinarian to assess the kidneys and urinary tract.
  • Blood clotting tests – Prothrombin time or activated partial thromboplastin time to evaluate the blood’s ability to clot.


Treatment depends on the cause of the hematuria and may include:

  • Antibiotics to treat urinary tract infections.
  • Prescription diet to alter the pH of urine and/or dissolve urinary stones.
  • Increase water consumption to dilute the urine, which may include changing to a canned diet and/or encouraging the cat to drink more water by flavouring water or water fountains.
  • Surgery to remove bladder or kidney stones.
  • Surgery to remove tumours which may be followed up with chemotherapy.
  • Vitamin K is used to treat blood clotting disorders/rat poisoning.
  • Blood transfusion may be required for cats with blood clotting disorders as well as specific treatment to address the underlying cause.
  • Corticosteroids to slow down platelet destruction in cats with primary thrombocytopenia.