Seeing pink or red urine is frightening, and that is understandable. Blood in the urine (medically, haematuria) does not always mean something serious, but it always deserves a visit to a urologist. Here is why it happens, which tests are done and when to go to A&E.
Two types of haematuria
- Visible (gross) haematuria: the urine looks pink, red or tea-coloured, sometimes with small clots.
- Microscopic haematuria: the urine looks normal, but a test finds red blood cells. It is often discovered by chance in a routine check-up.
Note: not every red colour is blood. Some foods (such as beetroot) and some medicines can colour the urine. A simple urine test clears it up.
Most common causes
- Urinary tract infection (cystitis): usually with burning and frequent urge to urinate.
- Kidney stones: often with severe pain in the lower back or side (renal colic).
- An enlarged prostate, in men over 50.
- Intense exercise or a recent injury.
- Blood thinners (anticoagulants or antiplatelets): they can make bleeding more likely but do not explain it on their own; the cause still needs to be investigated.
- Bladder or kidney tumours: less common, but haematuria — especially if visible and painless — is often their first and only symptom. That is why it should never be ignored.
Who is at higher risk?
It is especially important to investigate haematuria if you are over 40, smoke or used to smoke, or have worked with chemicals (dyes, paints, rubber or metal industries). Smoking is the main risk factor for bladder cancer.
Which tests are done?
- Urine test and culture, to confirm the blood and rule out infection.
- Blood test to check kidney function.
- Ultrasound or, when indicated, a CT urogram to examine the kidneys and urinary tract.
- Cystoscopy: a look inside the bladder with a thin camera. It is done in the clinic under local anaesthetic and takes a few minutes.
When to go to A&E
Go to the emergency department (Urgencias) or call 112 if you pass clots and cannot urinate, have a high fever or severe pain, or feel dizzy or weak.
In short
Blood in the urine can have simple causes, but do not wait for it to happen again: even if it goes away on its own, it should be investigated. Detecting a bladder or kidney problem early makes a big difference to treatment and outcome.
This article is for information only and does not replace a medical consultation.
Noticed blood in your urine? Book an appointment and we will look into it together. Consultations in English, Spanish and Russian at Fundació Puigvert, Barcelona.