What is Hematuria?

During routine visits to your health care provider, you are often asked to give a urine sample for testing. Many tests are done routinely, like checking for sugar (diabetes), bacteria (infection) and blood. Blood in the urine that you do not see is called "microscopic hematuria." This blood is only visible under a microscope. There are many causes and most are not serious, but may call for care by your health care provider.


  1. Urinary infection
  2. Enlarged Prostate in older men
  3. Kidney or bladder stones
  4. Period in women
  5. Prostate infection
  6. Kidney disease
  7. Kidney trauma
  8. Bladder cancer (mostly in smokers)
  9. Kidney cancer
  10. Blood thinning drugs (aspirin, coumadin/warfarin)
  11. Anti-swelling drugs (joint swelling and pain pills)
  12. Tough workout

When blood is found in the urine, health care providers want to make sure there is not a serious health issue involved such as a tumor in the kidney or bladder  . Urological cancers are rarely the cause of blood in the urine. Only about 2 or 3 of every 100 people with microscopic hematuria are found to have cancer.

When you actually see blood in the urine, it is called "gross hematuria." This is much more likely to be tied to a cancer or other health issue that needs medical care.


Repeat Urine Testing

The next step when microscopic blood is found is to repeat your urine test. This checks that the first finding was correct. You will need to get a mid-stream sample of urine. You will be told to collect your sample only after you have started to pass urine. Uncircumcised men will need to retract their foreskin to get a proper sample. Women will need to spread their labia and clean the opening of the urethra to get a clean sample.

Your health care provider will ask you questions about your health history. They will want to know about any infection, menstruation (period), kidney stones, drugs, or recent kidney injury. Simply repeating the urine test might be all that is needed if no further blood is found.

Cystoscopy Medical Illustration Copyright © 2015 Nucleus Medical Media, All rights reserved

If Testing Shows Blood and Protein

If protein is also found in the urine along with blood, then more urine tests and blood tests are needed. These tests are done to find out if kidney disease is the cause. Sometimes a kidney biopsy (putting a needle into the kidney) is done to find out if drugs are needed. Many of these health issues do not need treatment.

If Testing Shows Blood but No Protein

If a repeat urine test still shows blood and no protein is found, the next step would involve:

  • blood test for kidney function
  • cystoscopy (a procedure to look inside the bladder)
  • imaging test such as CT scan, MRI or ultrasound to look at the inner and outer parts of the kidney, ureters and bladder.

Most often no specific cause for blood in the urine is found. You will be asked to do another urine test 1 and 2 years later. If no further blood is found, then no further testing is needed. If you still have blood in your urine, these tests will likely be repeated.

What Increases the Risk of Finding Cancer?

Cancers are not often the cause of microscopic blood in the urine. But there are many health issues that increase the chance that a bladder or kidney tumor is the cause. Seeing blood yourself in the urine ("gross hematuria") is the most worrisome. A history of smoking or current smoking will increase your health care provider's concern about finding cancer.

Issues that Increase the Chance of Cancer

  1. Age over 35 years
  2. Prior visible "gross" blood in the urine
  3. Cigarette smoking (past or current)
  4. Chemicals in the workplace
  5. Prior pelvic radiation for cancer
  6. Prior urological disorder or disease
  7. Irritative voiding symptoms (pain, infection)
  8. Chronic urinary tract infection


If you are told that you have microscopic hematuria, do not panic because most causes are not life threatening. Make sure that you get your urine test repeated right away. Your health care provider will then tell you whether you need to have further blood tests, urine tests or imaging tests such as x-rays and cystoscopy. Make sure to follow what your health care provider tells you to do, so that if there is a serious condition, it can be treated right away.