Microhematuria

What is microhematuria?

Microscopic hematuria (microhematuria) is when you have blood in your urine (pee), but when you go to the bathroom, your pee looks normal. The amount of blood in your pee is too small to see with the naked eye — you need a microscope to see it. The American Urological Association defines microhematuria (MAHY-kro-hee-muh-TOOR-ee-uh) as three or more red blood cells (RBCs) per high-powered field under the microscope.

What is trace lysed blood in pee?

Trace lysed blood in your pee is a type of microhematuria. “Trace” means a small amount — you can’t see it without a microscope. “Lysed blood” means that the walls of the red blood cells broke apart. In microhematuria, the red blood cell walls are still intact.

What are the symptoms of microhematuria?

Often, microhematuria doesn’t have any symptoms (asymptomatic). A healthcare provider usually discovers microhematuria when they order routine tests during a checkup.

If you do have symptoms, they may include:

• Peeing more than usual (frequent urination).
• Pain or burning when you pee (dysuria).
• Pain on either side of your lower back, just above your hips (flank pain).
• Fever.
• Foul-smelling pee.

What causes microhematuria?

Common microhematuria causes include:

• Urinary tract infections (UTIs).
• Your period (menstruation).
• Certain medications, including nonsteroidal anti-inflammatory drugs (NSAIDs), penicillin and anticoagulants.
• Vigorous exercise.
• Enlarged prostate (benign prostatic hyperplasia).
• Stones in your urinary system, including ureteral stones, kidney stones or bladder stones.
• Chronic kidney disease (CKD).
• Urethral strictures.
• Certain types of cancer, including bladder cancer, kidney cancer and prostate cancer.

In many cases, healthcare providers may not discover the cause of microhematuria.

What is the most common cause of microhematuria?

UTIs are the most common cause of microhematuria.

How often is microhematuria a sign of cancer?

About 3% of people who receive testing for microhematuria have cancer. But your cancer risk also depends on several factors, including:

• Your age.
• How severe your microhematuria is.
• Whether you smoke.

Is microhematuria contagious?

No, microhematuria isn’t contagious. UTIs are the most common cause of microhematuria, and they aren’t contagious.

Who does microhematuria affect?

Anyone can have microhematuria. It occurs in adults and children.

How is microhematuria diagnosed?

A healthcare provider will review your health history and ask you questions about your symptoms. They may ask questions such as:

• Have you had blood in your pee before?
• Has your weight changed recently?
• Do you smoke, vape or use other tobacco products?
• What medications do you take, including over-the-counter (OTC) medications or supplements?
• Do you use recreational drugs?
• Do you have a biological family history of cancer or blood in your pee?

If a provider suspects you may have blood in your pee, they may order tests to make an official microhematuria diagnosis.

What tests will be done to diagnose microhematuria?

A healthcare provider may order the following tests to diagnose microhematuria:

• Urinalysis. You’ll provide a pee sample, which the provider will send to a lab for analysis.
• Urine culture. A urine culture can help diagnose a UTI.
• Blood tests, including a complete blood count (CBC). Blood tests can help diagnose chronic kidney disease or another condition that may cause blood to enter your pee.
• Imaging tests, including a CT urogram. This helps providers get a detailed look at your urinary system.
• Kidney function tests. Kidney function tests are pee or blood tests that help determine how well your kidneys are working.
• Cystoscopy. A provider will insert a small, flexible tool with a light and camera at the end (cystoscope) into your urethra to examine your urethra and urinary bladder.
• Biopsy. A provider will use a needle to remove a small sample of organ tissue to check its health and diagnose a condition that may be affecting it. They may take a sample from your bladder, kidney or prostate.

How do you treat microhematuria?

Treating microhematuria depends on its cause. A healthcare provider may recommend:

• Antibiotics to treat a UTI.
• Medications to relax your prostate (e.g., tamsulosin, terazosin, doxazosin) or slow prostate growth (e.g., finasteride, dutasteride).
• Medications to help you pass a stone (e.g., tamsulosin, nifedipine).
• Avoiding NSAIDs or other medications that damage your kidneys.
• Making changes to your eating plans, including reducing the amounts of protein, salt and potassium you consume.
• Surgery to remove stones or prostate tissue.

If tests don’t reveal a cause, you may not need treatment. A provider may recommend a “watchful waiting” approach. That means monitoring your condition, but not providing any treatment unless your symptoms change. They may also recommend “surveillance.” This means they’ll perform follow-up testing, such as repeat urinalysis at a future date.

Can microhematuria be prevented?

It may not be possible to prevent microhematuria from occurring. But drinking plenty of fluids, especially water, can help. It’s especially helpful when you’re exercising.

You can also help decrease your chances of microhematuria by:

• Quitting smoking.
• Using NSAIDs only as recommended.
• Avoiding exposure to radiation and certain chemicals, including benzenes, aromatic amines and hydrocarbons.

When should I be worried about microscopic hematuria?

It depends on what’s causing blood in your pee. But in general, the outlook for microhematuria is good. Many causes resolve without treatment or go away pretty easily with treatment. A healthcare provider will give you a better idea of what to expect after they confirm microhematuria.

When should I see a healthcare provider?

You won’t know if you have microhematuria unless a healthcare provider performs tests. So, it’s important to talk to a provider if you have symptoms that relate to microhematuria, including changes to your peeing habits, fever or flank pain. If any of your symptoms are severe, it’s a good idea to go to urgent care.

Contact a provider right away if you have a history of microhematuria and can see blood in your pee.

What questions should I ask a healthcare provider?

You may want to ask your provider:

• What tests do you recommend to diagnose microhematuria?
• What’s causing microhematuria?
• Do I need treatment?
• If I need treatment, what do you recommend?
• Will microhematuria come back?

Can you live with microscopic blood in your urine?

Most people who have microhematuria don’t need treatment. You may only need treatment if a stone or more serious condition is causing microhematuria.