What Does Blood in Urine Look Like? 5 possibilities.
Our content is not intended nor recommended as a substitute for medical advice by your doctor. Use for informational purposes only.
Blood in the urine may look red, pink, or brown. Also, blood in urine may contain clots or blood strings with reddish urine. Moreover, you may have microscopic blood in urine with normal urine appearance.
Common appearances of blood in the urine include:
- Reddish or pinkish urine.
- Brown urine.
- Blood clots or strings of blood in the urine.
- Bloody urethral discharge.
- Normal urine.
1. Red or pink urine.
The most common look of blood in urine is pink or reddish discoloration of the urine. It often appears throughout the urine stream.
Two factors influence the depth of the red color:
- The severity of bleeding.
- The amount (concentration of urine).
Blood in urine shifts towards the deep red color when the bleeding is massive or if the urine is scanty (oliguria).
On the other hand, slight or mild hematuria appears as pinkish discoloration of urine.
Hematuria (blood in urine) may come and go for a few days. Most causes are often benign, but you must consult your doctor if you have unexplained hematuria.
2. Brown urine.
Blood in the urine may appear brown, tea-colored, or cola-colored. This is common for hematuria of glomerular origin.
The glomerulus is the most important functional unit in the kidney. It is a microscopic apparatus that filters urine.
Some diseases may affect the glomerulus (glomerulonephritis), leading to glomerular hematuria, which is:
- Brown, reddish-brown, smoky brown, or cola-colored urine.
- Without blood clots.
- It may be associated with proteinuria (which appears in laboratory tests or manifests as foamy urine).
The most common disease of glomerular hematuria are:
- IgA nephropathy.
- Thin basement membrane disease.
- Alport syndrome.
However, brown urine doesn’t always mean glomerular bleeding, as it may also occur due to other causes of hematuria, such as infection or stones.
Moreover, brown urine doesn’t always mean hematuria, as it may be due to other pigments such as bilirubin (as with liver and biliary diseases).
3. Blood clots.
Blood clots look like small red masses of clotted blood (sometimes as strings or threads of blood) in urine. The urine containing the blood clots is usually reddish or pinkish.
Significance of blood clots in urine:
- Blood clots often mean significant (copious) bleeding, like kidney stones or bladder cancer.
- Also, the presence of blood clots in urine excludes glomerular causes (such as IgA nephropathy), which is considered a worrisome cause of hematuria.
Common causes of blood clots in urine include:
- Urinary tract stones.
- Urinary bladder cancer.
- Other urinary tract cancer, such as kidney cancer, prostate cancer, etc.
- Trauma to the urinary tract (kidney, bladder, ureter, or urethral trauma).
- Severe UTI.
- Others include benign kidney tumors, adult polycystic kidney disease, arteriovenous malformation, etc.
Complications of blood clots in urine:
The presence of blood clots in urine means the bleeding of the urinary tract is significant. This may lead to two main complications:
- Obstruction of the bladder outlet by the blood clots may lead to urinary retention (severe urge to pee but unable to pass urine).
- Prolonged blood clots in urine may cause significant anemia (pallor, shortest of breath, lightheadedness, palpitations, and headache).
4. Bloody urethral discharge.
Blood may come out from the urethra (without urine). In such cases, bloody discharge comes out spontaneously from the urethra. The bloody discharge may be mixed with pus or may be in the form of pure blood (sometimes, with blood clots).
Common causes of bloody urethral discharge without urine:
- Urethral trauma.
- Urethral diverticulum.
- Infectious urethritis (such as gonorrhea and chlamydia infection).
5. Normal urine (microscopic hematuria).
Blood in the urine may not be visible to the naked eye. In such cases, your urine analysis may show RBCs (red blood cells) in urine which is considered (microscopic hematuria).
In such a case, the blood appears completely normal (amber-yellow). Microscopic hematuria usually means that bleeding is minimal.
Microscopic hematuria in urine analysis occurs due to the same causes as gross hematuria.
Common causes include stones, infections, and exercise-induced hematuria. However, if no cause is identified, you should undergo a thorough investigation to detect the cause of hematuria.
Causes of blood in urine and when to worry:
The table below summarizes all the possible causes of hematuria (reference).
|1. benign or malignant kidney tumors.|
|2. Glomerulonephritis (IgA nephropathy, Thin basement membrane disease, or Alport syndrome).|
|3. Adult Polycystic Kidney Disease (APKD)|
|4. Medullary sponge kidney.|
|5. Pyelonephritis (kidney infection).|
|6. Kidney distension with urine (hydronephrosis).|
|7. Increased excretion of calcium or uric acid in urine.|
|8. Severe (malignant) hypertension.|
|9. Obstruction of the renal artery or renal vein.|
|10. Arteriovenous malformation (abnormal blood vessels of the kidney).|
|11. Papillary necrosis (with sickle cell disease).|
|1. Malignant ureteric tumor.|
|2. Stone ureter.|
|3. Stricture (narrowing) in the ureter.|
|5. Post-surgery (fistula between the iliac vessels and the ureter or ureteroiliac fistula).|
|URINARY BLADDER CAUSES|
|1. UB cancer (most serious).|
|2. Cystitis (UTI).|
|3. UB stone.|
|4. UB radiation.|
|PROSTATE & URETHRA|
|1. BPH (benign prostatic hypertrophy).|
|2. Prostatic cancer.|
|3. Prostatic procedures such as taking a biopsy or operations.|
|4. Trauma during urinary catheter insertion.|
|5. Urethritis (inflammation of the urethritis).|
|6. Urethral diverticulum.|
|ANYWHERE (KIDNEY, URETER, BLADDER, OR URETHRA)|
|1. UTI (infection with bacteria, viruses, or fungi).|
|5. Exercise-induced hematuria.|
|6. Recent interventions such as lithotripsy.|
|7. Bleeding disorders or anticoagulant medications.|
|8. Endometriosis of the urinary tract.|
|2. Drugs (Pyridium, phenytoin, rifampin, nitrofurantoin).|
|3. Red pigments in urine as myoglobinuria|
When to worry about hematuria:
- Painless blood in urine in old age (>50 years), especially in male smokers (high risk of malignancy).
- Worsening pain (renal colic or bladder pain).
- Blood clots with darkening hematuria that doesn’t improve after a few urinations.
- Blood clots that don’t easily pass during urination.
- Development of urine retention.
- Pallor, shortening of breath, fast heartbeats, or fainting attacks.