Hematuria is simply the presence of red blood cells in urine. You might think blood in your pet’s urine would be obvious to you because you can’t imagine not being aware of it. But in our dogs and cats, sometimes we don’t have any clue at all that hematuria exists until a veterinarian requests a urine sample for some other reason. In fact, it is not unusual to stumble across evidence of urinary problems, including hematuria, when running routine, wellness lab tests in apparently healthy animals—another good reason to request regular wellness tests. READ MORE for details on the symptoms of hematuria.