Finding blood in your urine can be very frightening and must be investigated by a urologist.
If you notice bright red blood in your urine or if your urine has turned red or brown because it has blood in it, see your GP urgently.
Sometimes urine may contain only a small amount of blood invisible to the naked eye. This only becomes apparent when a urine test is carried out for something else. This still needs to be investigated by your doctor as healthy urine should not contain any detectable amounts of blood. This, however, is less of a concern than seeing it.
The medical name for blood in the urine is haematuria. If blood in the urine is obvious with the naked eye, it is called "macroscopic" or "visible haematuria". If the blood can only be detected with laboratory testing, it is called "microscopic", or "non-visible".
The blood will have come from somewhere within the urinary tract – the kidneys, ureters or bladder.
This page outlines the most common reasons for blood in the urine, to give you an idea of what may be causing the problem. However, this guide should not be used to self-diagnose your condition and it's important to see your GP for a proper diagnosis.
Is there definitely blood in your urine?
Before you read on, it's worth considering whether you have recently eaten beetroot as this can colour the urine pink and cause unnecessary alarm. Some medicines, such as the antibiotic Rifampicin, can also turn your urine red or brown.
Check that the blood is actually coming from your urine and not your vagina (if you're a woman) or back passage.
Common causes of blood in urine
- Bladder infection -UTI (urinary tract infection) – which typically also causes a burning pain when you urinate.
- Kidney infection (pyelonephritis) – which may also cause a high temperature and pain in the side of your tummy.
- Kidney stones – which may be painless but can sometimes block one of the tubes coming from your kidneys causing severe and often agonising pain.
- Urethritis – inflammation of the tube that carries urine out of the body (urethra) - it's often caused by a sexually transmitted infection (STI) such as chlamydia.
- Enlarged prostate gland – this is a common condition in older men and nothing to do with prostate cancer - an enlarged prostate gland will press on the bladder and may also cause problems such as difficulty urinating and a frequent need to urinate.
- Bladder cancer – this usually affects adults aged over 50 and is often related to smoking. It can also cause irritation to the bladder making you urinate more often and more urgently.
- Kidney cancer – this also usually affects adults aged over 50, it can cause persistent pain below your ribs and a lump in your tummy though most commonly it is discovered after an episode of haematuria or incidentally on a scan.
- Prostate cancer – this is usually only seen in men aged over 50 and usually progresses very slowly. Other symptoms can include needing to urinate more frequently and urgently and difficulty emptying your bladder.
- Bladder stones - these tend to be associated with difficulties passing urine.
- Medical causes - kidney diseases can also present with blood in the urine. Blood thinners such as Warfarin, especially if the levels are too high can also cause bleeding.
Referral to a specialist
Tests to investigate the cause of blood in your urine can include:
- Urine tests - to rule out infection and look for any abnormal cells.
- Blood tests - to look at kidney function and after a discussion maybe a PSA (Prostate specific antigen test) in men.
- Imaging - this is usually in the form of ultrasound or CT to look at the kidneys and ureter tubes.
- Cystoscopy - this can be performed under a local anaesthetic or a general anaesthetic and looks at the lining of the bladder to make sure that no abnormalities are seen.
In some cases no cause for the blood is deteceted, especially if the blood was only microscopic. If any abnormality is found I will discuss this with you and suggest a plan for further investigation or treatment.