Hematuria: Symptoms and Causes

Hematuria may be a sign of a bacterial or viral infection, but also of more complicated conditions such as bladder or prostate cancer. Read on to learn more!
Hematuria: Symptoms and Causes
Leonardo Biolatto

Written and verified by the doctor Leonardo Biolatto.

Last update: 27 May, 2022

The word “hematuria” is the medical term used to define the presence of blood in the urine. Seeing blood in your urine can be scary. However, many different things can cause this condition, and not all of them are serious.

Sometimes, the blood can be seen with the naked eye. However, this doesn’t happen in all cases. Therefore, professionals divide hematuria into two main types: gross and microscopic. Doctors may request certain medical tests to diagnose microscopic hematuria.

A lot of people go to the doctor due to this condition. Its prevalence rate is approximately 16% of the general population. Also, as we mentioned above, it can be a symptom of a wide variety of conditions, from an infection to cancer. Therefore, it’s important to know what it is, as well as its symptoms and causes.

In this article, we’ll explain the most important aspects of hematuria.

What’s hematuria?

Under normal conditions, urine contains no blood. Hematuria is defined as the presence of red blood cells in the urine, observed by certain laboratory techniques. Hematuria occurs because the kidneys or other parts of the urinary tract let blood cells pass through to the urine. Urine may adopt a red color or remain the same. This marks the difference between gross (blood you can see) or microscopic (blood you can’t see).

A woman peeing.

This article may interest you: What the Color of Urine Says About Your Health

The main causes of hematuria

In many cases, finding the specific cause of hematuria isn’t possible. However, the most common processes that cause blood to pass through to the urine are:

  • Urinary tract infections. These are relatively common, especially in women. This is because the female urethra is close to the anus, and bacteria present therein can easily pass into the urethra.
  • Kidney infections. This condition is called pyelonephritis. Bacteria can reach the kidneys via the blood or ureters.
  • Prostate problems. When the prostate enlarges, which tends to occur with age, it compresses the urethra. This can block the flow of urine and cause hematuria. The same applies to prostate infections.
  • Bladder or kidney stones. Some minerals present in urine tend to build up. They solidify and form crystals that turn into small stones. When these stones run through the urinary tract, they can block it, leading to blood in the urine.
  • Cancer. Hematuria may be a sign of bladder, prostate, or kidney cancer. However, it usually manifests in advanced stages, making diagnosis difficult.
  • Glomerulonephritis. This condition is characterized by inflammation of glomeruli, tiny kidney filters. Diabetes, infections, blood diseases, or other processes can trigger this condition.
  • Certain medications, such as anticoagulants or cancer-fighting drugs, can also cause this.

As you can see, many things can cause hematuria. Scientists have even linked hematuria with strenuous exercise, as well as trauma or dehydration. Therefore, it’s important to go see a doctor to determine the cause.

A woman who needs to pee.

The symptoms of hematuria

Macroscopic hematuria manifests as red or brownish urine. Usually, it isn’t painful and isn’t accompanied by other symptoms. However, the manifestation of certain symptoms can guide the diagnosis of the cause.

For example, fever and low back pain may be indicative of a kidney infection. If hematuria is accompanied by increased urination or a burning sensation during urination, the cause usually lies in the lower urinary tract. Moreover, asymptomatic and continuous hematuria that’s accompanied by clots may be caused by a kidney tumor.

That’s one of the reasons why it’s essential for men 40 and older to get prostate exams.

You might also like this article: Urine Smells Bad for These 8 Reasons


As we explained in this article, hematuria may be related to many diseases. Moreover, in some cases, it isn’t visible to the naked eye. Therefore, it’s important to get regular medical checkups. We recommend getting urine tests regularly to detect the possible presence of blood.

Don’t forget to keep a close eye on your urine. You have to watch out for the color of your urine, as well as the frequency and any abnormal sensations, as any alteration could be indicative of a disease. Make sure to ask your doctor if you have any questions.

All cited sources were thoroughly reviewed by our team to ensure their quality, reliability, currency, and validity. The bibliography of this article was considered reliable and of academic or scientific accuracy.

This text is provided for informational purposes only and does not replace consultation with a professional. If in doubt, consult your specialist.