Toto ki te mimi Blood in the urine (haematuria)

Blood in wee (urine) is called haematuria. When there is lots of blood in your wee, you can see it with the naked eye as it looks red or pink. You cannot see very small amounts of blood in your wee. But it can be picked up when a urine sample is looked at under a microscope or by using a urine dipstick.

Causes of blood in urine

Often the cause is not found, but testing is needed to rule out important causes.

The most common causes are a urine infection (UTI) or a kidney infection (pyelonephritis).

Other causes include:

  • cancer of the bladder, kidney or prostate
  • kidney stones
  • urethritis inflammation of the urethra (the tube you pass wee through)
  • prostate enlargement
  • medications such as blood thinning medicines
  • glomerulonephritis (inflammation of the blood vessels in the kidney).

Not all red or dark looking wee means blood is present. Sometimes it can be due to eating certain foods such as beetroot, rhubarb or blackberries or taking some drugs such as rifampicin. Extreme exercise can also cause muscle breakdown, which can cause kidney damage and change the colour of wee.

If you think you have blood in your wee you should see your healthcare provider.

Diagnosing blood in urine

Your healthcare provider will examine you and ask questions about your general health and about the blood in your wee.

The first test you will need is a urine test to check for the presence of blood or an infection. Some people may need to have this test more than once.

If you do not have a urine infection and continue to have blood in your wee, you'll need further tests. These depend on your age and if the blood is visible to the naked eye or only visible under a microscope.

These tests include:

  • a urine test to check for infection and to look for protein
  • a blood test to check your how well your kidneys are working
  • tests to look for the possibility of bladder cancer — such as a urine test and either a CT scan or an ultrasound.

Treating blood in urine

If you have a urine infection, the first step is for your doctor to treat it with antibiotics before retesting your wee to see if the blood has gone.

Your healthcare provider will consider all your information and test results. Sometimes it is not possible to work out the exact cause of blood in your urine. If your tests are all normal, they will reassure you and arrange any further follow up if needed. If any of the tests are positive or suggest further assessment is needed, they will refer you to a urologist for specialist assessment.

At the urology department, you may need to have a cystoscopy to identify and sample any problems in your bladder. In this test, a special type of thin telescope is inserted through your urethra (the tube you pass urine through) and into your bladder.

If no cause is found, the specialist may recommend that you and your healthcare provider keep monitoring your wee and blood pressure. Sometimes monitoring is all that is needed. Sometimes tests need to be repeated, or your healthcare provider might refer you back to the urology department.

Clinical review

This content was written by HealthInfo clinical advisers. It has been adapted for Health Information and Services.

Clinical advisers — HealthInfo (external link)

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