Different conditions and diseases can cause hematuria, which is the medical term for blood in your urine. These can include infections, kidney disease, and rare blood disorders, among other causes.

The blood may be visible or in such small quantities that it can’t be seen with the naked eye. Any blood in the urine can be a sign of a serious health problem, even if it happens only once. Ignoring hematuria can lead to the worsening of serious conditions like cancer and kidney disease, so you should talk to your doctor as soon as possible.

Your doctor can analyze your urine and order imaging tests to determine the cause of the hematuria and create a plan for treatment.

There are two main types of hematuria: gross hematuria and microscopic hematuria.

Gross hematuria

If there’s enough blood in your urine that your urine appears pink or red or has spots of visible blood, you have “gross hematuria.”

Microscopic hematuria

When you can’t see the blood because the amount is so small, you have “microscopic hematuria.” Only a lab test that detects blood or looking at a sample of urine under a microscope can confirm microscopic hematuria.

There are many possible causes for hematuria. In some cases, the blood may be from a different source.

Blood can appear to be in the urine when it’s really coming from the vagina in women, the ejaculate in men, or from a bowel movement in either men or women. If the blood is truly in your urine, there are several potential causes.

Infection

Infection is one of the most common causes of hematuria. The infection could be somewhere in your urinary tract, your bladder, or in your kidneys.

Infection occurs when bacteria move up the urethra, the tube that carries urine out of the body from the bladder. The infection can move into the bladder and even into the kidneys. It often causes pain and a need to urinate frequently. There may be gross or microscopic hematuria.

Stones

Another common reason for blood in the urine is the presence of stones in the bladder or kidney. These are crystals that form from the minerals in your urine. They can develop inside your kidneys or bladder.

Large stones can cause a blockage that often results in hematuria and significant pain.

Enlarged prostate

In men who are middle-aged and older, a fairly common cause of hematuria is an enlarged prostate. This gland is just beneath the bladder and near the urethra.

When the prostate gets bigger, as it often does in men at middle age, it compresses the urethra. This causes problems with urinating and may prevent the bladder from emptying completely. This can result in a urinary tract infection (UTI) with blood in the urine.

Kidney disease

A less common reason for seeing blood in the urine is kidney disease. A diseased or inflamed kidney can cause hematuria. This disease can occur on its own or as part of another disease, such as diabetes.

In children ages 6 to 10 years, the kidney disorder post-streptococcal glomerulonephritis may cause hematuria. This disorder can develop one to two weeks after an untreated strep infection. Once common, it’s rare today because antibiotics can quickly treat strep infections.

Cancer

Cancer of the bladder, kidney, or prostate can cause blood in the urine. This is a symptom that often occurs in advanced cancer cases. There may not be earlier signs of a problem.

Medications

Certain medications can cause hematuria. These include:

Less common causes

There are a few other causes of hematuria that aren’t very common. Rare blood disorders such as sickle cell anemia, Alport syndrome, and hemophilia can cause blood in the urine.

Strenuous exercise or a blow to the kidneys can also cause blood to show up in the urine.

If you’re seeing your doctor for hematuria, they’ll ask you about the amount of blood and when you see it during urination. They’ll want to know how often you urinate, any pain you’re experiencing, if you see blood clots, and what medications you’re taking.

Your doctor will then give you a physical examination and collect a sample of your urine for testing. The analysis of your urine can confirm the presence of blood and detect bacteria if an infection is the cause.

Your doctor may order imaging tests such as a CT scan, which uses radiation to create an image of your body.

Another possible test your doctor may want to do is a cystoscopy. This involves using a small tube to send a camera up your urethra and into your bladder. With the camera, your doctor can examine the interior of your bladder and urethra to determine the cause of your hematuria.

Since some of the causes of blood in the urine are serious, you should seek medical attention the first time you see it. You shouldn’t ignore even a small amount of blood in your urine.

Also see your healthcare provider if you don’t see blood in your urine but experience frequent, difficult, or painful urination, abdominal pain, or kidney pain. These may all be indications of microscopic hematuria.

Seek emergency help if you can’t urinate, see blood clots when you urinate, or have blood in your urine along with one or more of the following:

  • nausea
  • vomiting
  • fever
  • chills
  • pain in your side, back, or abdomen

The cause of your hematuria will determine what type of treatment you receive.

If an infection, such as a UTI, is responsible for your hematuria, your healthcare provider will prescribe antibiotics to kill the bacteria causing the infection.

Hematuria caused by large kidney stones can be painful if left untreated. Prescription medications and treatments can help you pass stones.

Your healthcare provider may suggest using a procedure called extracorporeal shock wave lithotripsy (ESWL) to break up the stones.

ESWL involves using sound waves to break the kidney stones into tiny pieces that can pass in your urine. The procedure usually takes around one hour and may be done under light anesthesia.

Your healthcare provider may also use a scope to remove your kidney stones. To do this, they pass a thin tube called a ureteroscope through your urethra and bladder into your ureter. The scope is equipped with a camera to locate the stones.

Your healthcare provider will use special tools to snare the stones and remove them. If the stones are large, they will be broken into pieces before removal.

If an enlarged prostate is causing your hematuria, your healthcare provider may prescribe medication, such as alpha blockers or 5-alpha reductase inhibitors. In some cases, surgery may be an option.

Some of the causes of blood in the urine are serious, so you should contact your healthcare provider if you notice this symptom.

If the symptom is due to cancer, ignoring it can lead to an advancement of the tumors to the point that treatment is difficult. Untreated infections can ultimately lead to kidney failure.

Treatment can help reduce symptoms if the cause of hematuria is an enlarged prostate. Ignoring it may lead to discomfort from needing to urinate frequently, severe pain, and even cancer.

Preventing hematuria means preventing the underlying causes:

  • To prevent infections, drink plenty of water daily, urinate immediately after sexual intercourse, and practice good hygiene.
  • To prevent stones, drink plenty of water and avoid excess salt and certain foods like spinach and rhubarb.
  • To prevent bladder cancer, refrain from smoking, limit your exposure to chemicals, and drink plenty of water.