Blood in Urine (Men): What It Could Mean and What to Do

What does 'blood in urine' actually mean?

The medical term is hematuria. It comes in two forms:

• Gross hematuria: visible to the eye — urine that appears pink, red, brown, or tea-colored, or contains frank clots.
• Microscopic hematuria: found only on urinalysis; urine looks completely normal. The 2020 AUA/SUFU guideline defines clinically significant microscopic hematuria as three or more red blood cells per high-power field on a properly collected specimen 1Ref 1Barocas DA, Boorjian SA, Alvarez RD, et al. (2020).Microhematuria: AUA/SUFU Guideline.Definition of clinically significant microscopic hematuria; risk stratification for workup intensity; recommendation against dismissing hematuria without evaluation.

Both forms deserve evaluation. Gross hematuria tends to prompt faster workup because it is alarming, but microscopic hematuria carries a meaningful risk of underlying pathology and is not something to dismiss.

A practical note: beets, berries, certain medications, and some supplements can temporarily discolor urine red or pink without any blood cells present. A urinalysis with microscopy distinguishes between pigmented urine and true hematuria — do not assume it is dietary unless a urine test confirms no red blood cells.

What are the most common causes of blood in urine in men?

### Urinary tract infection (UTI) UTIs cause hematuria by inflaming the bladder wall. They are less common in men than women but do occur, particularly in men over 50, those with an enlarged prostate, or those with structural urinary tract abnormalities. Typical clues: burning on urination, frequency, urgency, and sometimes fever.

### Kidney stones Kidney stones affect roughly 10–11% of men in the United States and are a leading cause of hematuria 2Ref 2Scales CD Jr, Smith AC, Hanley JM, Saigal CS (Urologic Diseases in America Project) (2012).Prevalence of Kidney Stones in the United States.Kidney stone prevalence approximately 10-11% in US men; peak incidence age 40-49. The peak age of incidence in men is 40–49. Stones cause blood in the urine by traumatizing the lining of the ureter or bladder as they pass. The classic presentation is severe flank or groin pain that comes in waves — but smaller stones can occasionally bleed with little or no pain.

### Benign prostatic hyperplasia (BPH) and prostatitis The enlarged prostate seen with BPH develops increased vascularization that can bleed into the urinary stream 3Ref 3Vasdev N, Kumar A, Veeratterapillay R, Thorpe AC (2013).Hematuria secondary to benign prostatic hyperplasia: retrospective analysis of 166 men identified in a single one stop hematuria clinic.BPH as a recognized cause of hematuria in men; vascular mechanism underlying prostatic bleeding. BPH is very common in men over 50 and is an established cause of hematuria seen in hematuria clinics. Prostatitis — inflammation or infection of the prostate — can also produce hematuria, often alongside pelvic pain or perineal discomfort.

### Bladder cancer Bladder cancer is the fourth most common cancer in American men. Painless gross hematuria is the presenting symptom in most newly diagnosed cases 4Ref 4Rink M, Crivelli JJ, Shariat SF, Chun FK, Messing EM, Soloway MS (2015).Smoking and Bladder Cancer: A Systematic Review of Risk and Outcomes.Painless hematuria as the predominant presenting symptom of bladder cancer; smoking as major risk factor. Smoking is the single strongest modifiable risk factor: current smokers carry roughly three times the bladder cancer risk of non-smokers, and a significant smoking history warrants prompt urological evaluation when hematuria is present 5Ref 5Rink M, Crivelli JJ, Shariat SF, Chun FK, Messing EM, Soloway MS (2015).Smoking and Bladder Cancer: A Systematic Review of Risk and Outcomes.Current smokers carry approximately 3x the risk of bladder cancer compared to non-smokers; smoking is the strongest modifiable risk factor. Age over 50, male sex, and occupational exposure to certain chemicals (dyes, rubber, aromatic amines) also increase risk.

### Kidney (renal) cancer Renal cell carcinoma can present with painless hematuria, often without any other early symptoms. It is less common than bladder cancer but should be considered, particularly with persistent unexplained hematuria, a flank mass, or significant weight loss.

### Exercise-induced hematuria Vigorous exercise — particularly long-distance running — is a well-recognized benign cause 6Ref 6Lippi G, Sanchis-Gomar F (2019).Exertional hematuria: definition, epidemiology, diagnostic and clinical considerations.Exercise-induced hematuria: mechanism (bladder wall trauma, renal ischemia), typical resolution within 24-48 hours of rest. The mechanism involves bladder wall trauma from the posterior wall contacting the bladder neck during repeated impact, or transient renal ischemia. The key clinical feature is spontaneous resolution within 24–48 hours of rest. Blood that persists beyond 72 hours of rest, or recurs without exercise, requires full evaluation.

### Other causes Post-streptococcal glomerulonephritis, IgA nephropathy, and other kidney diseases can cause tea-colored or brown urine from inflammation within the glomeruli. Anticoagulant medications (warfarin, rivaroxaban, apixaban) lower the threshold for bleeding but do not themselves explain hematuria — an underlying structural source should still be sought.

Why does hematuria always get a formal workup?

Because bladder cancer and kidney cancer can present with painless hematuria — no pain, no other symptoms — standard guidelines recommend not dismissing hematuria as 'probably benign' without at least a basic investigation 1Ref 1Barocas DA, Boorjian SA, Alvarez RD, et al. (2020).Microhematuria: AUA/SUFU Guideline.Definition of clinically significant microscopic hematuria; risk stratification for workup intensity; recommendation against dismissing hematuria without evaluation.

The 2020 AUA/SUFU Microhematuria Guideline (updated in 2025) uses a risk stratification system based on age, smoking history, sex, prior gross hematuria, and degree of bleeding to guide the intensity of workup 1Ref 1Barocas DA, Boorjian SA, Alvarez RD, et al. (2020).Microhematuria: AUA/SUFU Guideline.Definition of clinically significant microscopic hematuria; risk stratification for workup intensity; recommendation against dismissing hematuria without evaluation7Ref 7Barocas DA, Lotan Y, Matulewicz RS, et al. (2025).Updates to Microhematuria: AUA/SUFU Guideline (2025).2025 update to AUA/SUFU microhematuria guideline: revised risk stratification, updated role of urine-based tumor markers and cytology, surveillance guidance. Higher-risk patients receive imaging plus cystoscopy; lower-risk patients may need only a repeat urinalysis after a defined interval.

This is not meant to alarm anyone. The large majority of hematuria evaluations identify a benign cause. But catching a bladder tumor or renal mass early significantly changes outcomes — this is exactly what structured evaluation is designed to accomplish.

What happens at the appointment?

A clinician evaluating hematuria will typically:

1. Take a detailed history — when it started, color, whether it's constant or intermittent, associated symptoms (pain, fever, urinary symptoms), exercise habits, smoking history, medications, prior episodes, and any recent trauma or illness. 2. Perform a urinalysis with microscopy — to confirm red blood cells are present (not just pigment), look for infection, protein, or casts that suggest kidney disease, and check for white cells indicating inflammation. 3. Order a urine culture if infection is suspected. 4. Consider imaging — the standard is a CT urogram (a CT scan of the kidneys, ureters, and bladder), which is highly sensitive for kidney stones, renal masses, and ureteral pathology. It is the preferred first-line imaging study in most guidelines. 5. Refer to urology for cystoscopy in intermediate- and high-risk patients — cystoscopy uses a small flexible camera passed through the urethra to look directly inside the bladder. It is the definitive way to identify or exclude bladder cancer. 6. Check PSA in older men to assess for prostate pathology contributing to the bleeding.

For a man in his 30s with a first episode clearly linked to strenuous exercise, the workup may be as simple as a urinalysis after a rest period. For a 60-year-old man with a 30-pack-year smoking history and painless gross hematuria, a full urological workup — imaging plus cystoscopy — is appropriate and timely.

Which factors change how urgently this is evaluated?

Several factors shift the clinical picture toward faster or more intensive evaluation:

| Factor | Why it matters | |---|---| | Age over 50 | Risk of bladder and kidney cancer rises significantly with age | | Smoking history | The strongest modifiable risk factor for bladder cancer 5Ref 5Rink M, Crivelli JJ, Shariat SF, Chun FK, Messing EM, Soloway MS (2015).Smoking and Bladder Cancer: A Systematic Review of Risk and Outcomes.Current smokers carry approximately 3x the risk of bladder cancer compared to non-smokers; smoking is the strongest modifiable risk factor | | Gross hematuria (visible blood) | Higher pre-test probability of malignancy than microscopic hematuria alone | | Painless hematuria | Absence of pain does not mean absence of serious cause — bladder cancer classically presents this way | | Recurrent episodes | A pattern of recurrence warrants prompt urological referral | | Blood thinners | Anticoagulants increase bleeding but do not explain hematuria — underlying source should still be investigated | | Family history of kidney disease | Polycystic kidney disease, hereditary nephritis (Alport syndrome), and other inherited conditions can cause chronic hematuria | | Recent streptococcal infection | Hematuria 1–3 weeks after strep throat or skin infection raises the possibility of post-streptococcal glomerulonephritis |

The BPH guideline notes that lower urinary tract symptoms alongside hematuria in older men warrant evaluation for both prostate and urothelial pathology 8Ref 8Lerner LB, McVary KT, Barry MJ, et al. (2021).Management of Lower Urinary Tract Symptoms Attributed to Benign Prostatic Hyperplasia: AUA Guideline Part I — Initial Work-up and Medical Management.BPH as cause of lower urinary tract symptoms and hematuria in men over 50; evaluation recommendations.

What should you bring to the appointment?

A clinician will ask about several things that are worth noting in advance:

• When the blood first appeared and whether it is constant or comes and goes
• What color the urine is (pink, red, brown, or containing clots)
• Whether it appeared after vigorous exercise, an illness, or an injury
• All current medications and supplements, especially blood thinners, NSAIDs, and aspirin
• Smoking history (past and present, approximate pack-years)
• Any prior episodes and what evaluation was done at that time
• Any associated symptoms: pain, fever, urinary symptoms, unintentional weight loss

If possible, note whether the blood appears at the start of urination, throughout, or only at the end — this can help localize the source (urethra/prostate vs. bladder vs. upper urinary tract).