Dog and Cat Urinary tract infections: leukocytes and nitrites
A positive reading for Leukocytes or Nitrites on the urine test is cause for consulting your veterinarian for further testing to confirm a urinary tract infection.
Positive reading for Leukocytes means that there are white blood cells (WBC) in the urinary tract. White blood cells enter the urinary tract when there is an infection in order to “stand guard” and ward off further infection.
Because bacteria produces Nitrite, there is usually a positive reading on the Nitrite value as well. If there is no Nitrite present, it is generally because there is not enough bacteria in the urine to cause Nitrites to be produced.