Hematuria – Blood in the Urine
Many patients are referred to see a urologist to evaluate the finding of hematuria, which means blood in the urine. Sometimes the patient has seen blood in the urine (this is macroscopic or gross hematuria). Other times, the referring doctor has seen microscopic amounts of blood in the urine, defined as more than 3 red blood cells per high power field of observation under a microscope. Whether it is gross blood or microscopic blood, it is not a normal event and may need evaluation.
- Foods causing red/pink urine
- Food coloring
- Medications causing red/orange urine
- Sulfasalazine (Azulfidine)
- Phenazopyridine (Pyridium)
- Brown or Dark urine may come from
- Fava beans
- Antimalarial drugs
- Some laxatives containing Senna or Cascara
- Liver disorders
- Extreme exercise
- Cervical or uterine diseases
- Causes & Symptoms
Causes & Symptoms
There are many things that can cause hematuria; below are some of the more common findings:
- Kidney, ureteral, or bladder stones
- Viral or bacterial urinary infections
- Benign prostatic hyperplasia (enlarged prostate)
- Benign or cancerous tumors of the kidneys, ureters, or bladder
- Trauma involving one or more of the organs of the urinary system
- Medications, especially blood thinners or aspirin-like compounds
- Kidney diseases
- Certain medical diseases, such as Sickle Cell trait or disease, and Lupus
- Long-distance running (resulting in irritation of the lining of the bladder)
- Prior pelvic radiation, or prior chemotherapy with selected drugs
- Smoking, which leads to a higher risk of developing kidney or bladder cancer
Often there are no symptoms when blood is found in the urine. If it is related to a urinary infection, it may burn when you urinate. If it is due to a kidney or ureteral stone, you may have flank or abdominal pain, nausea or vomiting. If it is related to a large prostate, there may be a slow stream, urinary urgency, and urinary frequency.
The diagnosis requires either gross blood in the urine or more than 3 red blood cells per high power field under the microscope. The urine will clue in to a number of possibilities. The following are some examples:
- The presence of bacteria would suggest a urinary infection
- The finding of white and red cells with crystals might support a diagnosis of a stone
- Clumps of cells (casts) and heavy protein content in the urine would suggest medical renal disease
A CT scan of the abdomen and pelvis is done before and after the administration of IV contrast. You may need a blood test to check your kidney function before you receive IV contrast for the CT scan. You need healthy kidneys to eliminate the contrast afterwards.
An MRI of the abdomen and pelvis or retrograde pyelograms (shooting contrast up the ureters via a cystoscope) are substitutes for a CT urogram, but less commonly ordered.
An office-based procedure with a flexible endoscope to inspect the urethra and bladder. In men, it also permits a look at the prostatic urethra. This test can help identify:
- Urethral narrowing
- Prostate obstruction or prostate bleeding
- Bladder tumors or inflammation
Possible additional tests
- PSA (prostate specific antigen) blood test – often done in men to screen for prostate cancer (which can occasionally cause hematuria)
- Blood and urine tests to diagnose kidney diseases, and/or a referral to a nephrologist who treats kidney diseases
- MRI or CT angiography for the diagnosis of rare disorders of blood vessels that bleed into the kidney – arteriovenous fistulae, hemangiomas or aneurysms
- Renal biopsy – when medical renal disease is suspected
Some examples of treatment based upon specific diagnoses include:
- If a bacterial urinary infection has caused hematuria, antibiotics are likely to make it resolve
- If there is a tumor of the kidney or bladder that causes the hematuria, removing the tumor will make it resolve
- If a large prostate has bled, sometimes time alone allows the hematuria to stop. On other occasions, some medications may be prescribed to help shrink the prostate or surgery to open up and cauterize the prostate.
Frequently Asked Questions
In general, we prefer the CT urogram – the injection of IV contrast allows us to see small filling defects (tumors) in the draining system of the kidneys. This is particularly important in people with additional risk factors: older patients, prior episodes of hematuria, smokers, history of previous pelvic radiation or chemotherapy.
What do you do if I cannot take IV contrast for a CAT scan?
There are often two reasons why people can’t take IV contrast: either they have reactions to the IV contrast, or their kidneys don’t work sufficiently to eliminate the contrast after the study is complete.
If you have a reaction to IV contrast (eg, itching, rash), you would receive a Benadryl and prednisone preparation to take by mouth prior. If you have had more serious reactions, such as shortness of breath, a non-contrast CT scan or perhaps an MRI may need to be the course of action.
If your kidney function will not permit IV contrast to be used, there is a good work-around called “Retrograde Pyelograms.” Your urologist looks into the bladder using an endoscope, then injects contrast up the ureters. This would avoid absorbing the contrast into your blood system while giving us the information we need.
If my CT scan is normal, do I really need the cystoscopy?
Yes. A CT scan cannot tell us if the prostate appears to obstruct the urethra or is bleeding into the urethra. They also cannot be relied on to diagnose small urethral small urethral lesions or strictures, and can easily mess a small cancer of the bladder.
Are there risks of having a CT scan or cystoscopy?
A CT exposes you to radiation, but it is not at all likely to cause cancer unless this study is done repeatedly. The IV contrast may cause itching or hives. Very rarely will the IV contrast lead to shortness of breath or low blood pressure (anaphylaxis).
Cystoscopy will occasionally lead to increased urinary bleeding or an infection. There are rare occasions when cystoscopy can cause more severe injury to the urethra or bladder.