Written and clinically reviewed by Dr Brendan Dias
Consultant Urologist & Robotic Surgeon · MBBS, MS (General Surgery), DrNB (Urology), IntFRCS (England), FUSANZ, FRACS (Urology)
Last clinically reviewed: 2 July 2026
Seeing blood in your urine can be alarming — and it should prompt you to see a doctor without delay. While many causes of haematuria (blood in the urine) are benign, the possibility of a more serious underlying condition, including bladder or kidney cancer, means that every episode deserves proper medical assessment. This guide explains the common causes, the red flags that matter most, and what to expect from a urological work-up.
What Is Haematuria?
Haematuria simply means blood in the urine. It is generally divided into two types:
- Visible (macroscopic) haematuria — blood that can be seen with the naked eye, turning urine pink, red or brown.
- Microscopic (invisible) haematuria — blood detected only on a urine dipstick or under the microscope, with no visible colour change.
Both types can indicate significant underlying disease and should not be ignored, although visible haematuria carries a higher likelihood of finding a serious cause on investigation.
Common Causes of Blood in Urine
Benign Causes
- Urinary tract infection (UTI) — often accompanied by burning, frequency and urgency
- Kidney or bladder stones — can cause intermittent visible blood, often with pain
- Benign prostatic hyperplasia (BPH) — an enlarged prostate can cause surface blood vessels to bleed
- Vigorous exercise — particularly long-distance running, causing transient haematuria
- Recent urological procedures — catheterisation or biopsy can cause temporary bleeding
More Serious Causes
- Bladder cancer — the most common cause of painless visible haematuria in adults over 50, particularly smokers
- Kidney cancer — can present with painless visible blood, sometimes with flank pain or a palpable mass
- Upper tract urothelial cancer — cancer of the lining of the kidney drainage system or ureter
- Glomerulonephritis — a kidney condition causing microscopic blood, usually managed by a nephrologist
Red Flags That Mean You Should See a Urologist Promptly
- Any episode of visible (macroscopic) blood in the urine, even if it clears up on its own
- Painless haematuria — the absence of pain does not make it less serious; in fact, painless bleeding is more concerning for cancer
- Haematuria with unexplained weight loss, fatigue, or a flank mass
- Age over 50, current or past smoking history, or occupational exposure to dyes and chemicals — these increase the risk of bladder cancer
- Persistent microscopic blood on repeat urine tests
A frequently misunderstood point is that a single episode of visible blood which then disappears does not mean the problem has resolved. This pattern — intermittent, painless visible haematuria — is in fact one of the most classic presentations of bladder cancer, and delaying assessment because symptoms "went away" is one of the most common reasons for delayed cancer diagnosis.
How Haematuria Is Investigated
Urine Tests
A urine sample is checked for infection, and a urine cytology test may be sent to look for abnormal (cancerous) cells shed into the urine.
Blood Tests
Kidney function and, in men, PSA (if age-appropriate) are checked as part of a complete assessment.
Imaging
A CT urogram — a CT scan with contrast dye timed to outline the kidneys, ureters and bladder — is the gold standard imaging test for haematuria, as it can detect kidney tumours, stones and upper tract abnormalities. Ultrasound may be used as an alternative in patients who cannot have contrast dye.
Cystoscopy
Cystoscopy is a telescope examination of the bladder performed under local anaesthetic in the rooms, or general anaesthetic in hospital. It is the only way to directly visualise the bladder lining and is essential for excluding bladder cancer, since small bladder tumours can be missed on CT scan.
What Happens If Something Is Found
If a bladder tumour is identified on cystoscopy, the next step is usually a transurethral resection of bladder tumour (TURBT) to remove and biopsy the tumour and determine how deeply it has invaded the bladder wall. Depending on the result, further treatment may range from surveillance and bladder instillation therapy to robotic radical cystectomy for muscle-invasive disease.
If a kidney stone is the cause, treatment options range from observation for small stones to ureteroscopy, shockwave lithotripsy (ESWL) or percutaneous nephrolithotomy (PCNL) for larger stones. If a kidney mass is found, further work-up and, if needed, robotic partial nephrectomy or robotic radical nephrectomy may be recommended.
Frequently Asked Questions
Is blood in urine always serious?
Not always, but it should never be ignored. Blood in the urine (haematuria) can be caused by benign conditions such as a urinary tract infection or kidney stone, but it can also be the first sign of bladder or kidney cancer. Any episode of visible blood in the urine — even a single episode that clears up on its own — needs assessment by a urologist.
What if the blood in my urine went away by itself?
Even if visible blood clears after a day or two, the underlying cause has not necessarily resolved. A one-off episode of painless visible haematuria is one of the classic early warning signs of bladder cancer, and it is precisely because it settles down that many people delay seeing a doctor. Investigation is still required.
What tests will a urologist do for blood in urine?
The standard work-up includes a urine test (to look for infection and abnormal cells), blood tests including kidney function, imaging of the kidneys and urinary tract (usually CT urogram or ultrasound), and a cystoscopy — a telescope examination of the bladder — to directly visualise the bladder lining.
Can exercise cause blood in urine?
Yes, vigorous exercise (particularly long-distance running) can cause transient microscopic or occasionally visible haematuria, thought to be related to bladder trauma or dehydration. However, this diagnosis should only be made after other causes have been excluded, and exercise-induced haematuria should resolve within 24–48 hours of rest.
Does microscopic (invisible) blood in urine need investigation?
Microscopic haematuria detected incidentally on a urine dipstick can also indicate significant underlying disease, particularly in patients over 50, smokers, or those with risk factors for bladder cancer. Persistent microscopic haematuria on repeat testing generally warrants referral to a urologist for further assessment.
Does Dr Dias investigate blood in urine in Melbourne?
Yes. Dr Brendan Dias provides prompt assessment of haematuria in Melbourne, including cystoscopy, CT urogram coordination, and, when needed, treatment of the underlying cause including bladder cancer surgery (TURBT and robotic cystectomy) and kidney stone treatment.
The Bottom Line
Blood in the urine is a symptom, not a diagnosis, and it should always prompt a visit to your GP or urologist. While many causes are benign, timely investigation — including cystoscopy and imaging — is the only way to reliably exclude serious conditions such as bladder or kidney cancer. Early detection significantly improves treatment outcomes, so if you notice blood in your urine, don't wait for it to happen again before seeking advice.