Blood in the urine (haematuria) - What does it mean?
Seeing blood in your urine can be alarming. In many cases, there is a straightforward explanation, but blood in the urine should always be assessed, particularly in adults.
The medical term for blood in the urine is haematuria. It can be either visible or non-visible (microscopic).
Visible haematuria
Visible haematuria means you can see blood in your urine. The urine may look pink, red or brown, and sometimes there may be blood clots.
Visible blood in the urine can have many causes, including:
urinary tract infections
kidney or bladder stones
an enlarged prostate
prostate or kidney problems
medications such as blood thinners
kidney disease
bladder, kidney or prostate cancer.
Importantly, visible haematuria does not necessarily mean you have cancer. However, because urinary tract cancers can sometimes cause blood in the urine without any other symptoms, visible haematuria should be investigated even if it occurs only once and then disappears.
Non-visible haematuria
Non-visible haematuria, sometimes called microscopic haematuria, means that blood is detected on a urine test but cannot be seen with the naked eye.
It is relatively common and may be discovered incidentally during a routine health check or investigation for another problem.
Non-visible haematuria can have many of the same causes as visible haematuria. Sometimes no underlying cause is found, particularly when the amount of blood is very small.
Whether further investigation is required depends on factors such as your age, smoking history, previous urinary problems, the amount of blood detected and whether you have any other symptoms.
What tests might I need?
The aim of investigation is to identify where the blood is coming from and, importantly, to exclude significant causes.
Your assessment may include:
Urine tests – to look for infection, blood and other abnormalities.
Blood tests – to assess kidney function and other relevant health factors.
Imaging – an ultrasound or CT scan may be recommended to examine the kidneys and urinary tract.
Cystoscopy – a small camera is passed through the urinary passage to examine the urethra, prostate and bladder. This is an important part of investigating many cases of haematuria.
Not everyone needs every test. Your urologist will determine the appropriate investigation based on your symptoms and individual risk factors.
When should I see a doctor?
You should arrange medical assessment if you notice blood in your urine, even if it is painless or only happens once.
You should seek more urgent medical attention if blood in the urine is associated with:
difficulty passing urine
blood clots preventing urination
severe pain
fever or chills
feeling very unwell.
Does blood in the urine mean cancer?
Often not. There are many possible causes of haematuria, and most people investigated for blood in the urine will not be diagnosed with cancer.
However, haematuria can sometimes be the earliest warning sign of cancers of the bladder, kidney or urinary tract. This is why it is important not to assume that blood in the urine is simply due to an infection, an enlarged prostate or blood-thinning medication without appropriate assessment.
What happens after the investigation?
In some people, a clear cause such as a urinary infection or stone is identified and treated.
In others, all investigations may be normal. This can be reassuring, although some patients may require follow-up depending on their individual risk factors.
The important thing is to find the cause where possible and make sure significant conditions (e.g cancer) have not been missed.
The bottom line
Blood in the urine should not be ignored.
Whether the blood is visible or only detected on a urine test, there are many possible causes ranging from simple and not needing any treatment, to more serious problems that require further investigation and treatment.
If you have noticed blood in your urine, a urological assessment can help determine the cause and provide reassurance or appropriate treatment.
This information is intended as a general guide and does not replace individual medical assessment.
