There are several possible causes of blood in a person’s urine with no pain. Causes include exercise, trauma, and kidney disease.

Hematuria is the medical term for when blood is present in urine. There are two types of hematuria:

  • gross hematuria
  • microscopic hematuria

Gross hematuria is when the blood is visible to the naked eye. With microscopic hematuria, the blood is harder to notice. It typically requires a microscope or urine test to identify.

In both cases, blood can occur in urine either with or without pain. There are several conditions and causes that can lead to blood in urine.

This article covers the main causes of visible blood in urine without pain and when to contact a healthcare professional.

A toilet in a tiled bathroom. Hematuria is blood in a person's urine, which can occur with no pain.Share on Pinterest
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Vigorous or strenuous exercise, such as long-distance running, can cause blood to visibly occur in urine.

Symptoms

When exercise causes hematuria, there are often no other symptoms present. The main characterizing feature is blood in the urine after physical activity without any notable impact to the region, plus the lack of blood in urine after rest.

Treatment

If there has been no genital or urinary trauma, and the blood disappears from urine after 72 hours, treatment is probably not needed.

However, if the association between exercise and blood in urine is unclear, a doctor may suggest taking tests to rule out other causes.

Angiomyolipoma is a condition that causes noncancerous tumors in the kidney. It can cause blood to occur in urine.

Symptoms

Aside from blood in urine, signs and symptoms of angiomyolipoma can include:

  • abdominal mass
  • urinary tract infection (UTI)
  • anemia
  • poor kidney function
  • shock
  • flank pain (pain in the middle of the back below the rib cage, which can be on one or both sides of the back)

However, angiomyolipoma can also have no symptoms.

Treatment

Appropriate treatment for angiomyolipoma varies between cases. It is important to be able to correctly identify the size and type of tumor to know how to manage it.

Healthcare professionals can use embolization to treat angiomyolipomas. Embolization uses particles to block blood vessels, which stops blood from entering a person’s urine.

Blunt trauma to the kidneys or urethra (the tube that carries urine from the bladder out of the body) can also cause blood in a person’s urine. Trauma can be either penetrating or blunt.

Blunt trauma results from a source of impact or force that doesn’t break the skin. Examples include:

  • car accidents
  • falls
  • being hit hard by a heavy object
  • crush injuries

Symptoms

The main symptom of blunt kidney trauma is blood in a person’s urine. A person may have no other symptoms, but sometimes bruises may be seen on their back or abdomen near the kidneys.

Trauma to the urethra can cause urine to leak into other body parts. Signs and symptoms include:

Treatment

A healthcare professional can determine appropriate treatment according to the type of trauma and injury.

If blunt trauma involves the upper areas, a healthcare professional may use a urinary catheter to assess the problem. When the source of blood is close to the opening, the injury may be from the urethra.

The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) states that kidney disease involving the glomeruli (known as glomerulonephritis) is a cause of blood in a person’s urine.

Glomeruli are a tiny network of blood vessels where blood is cleaned. They filter waste products from a person’s blood. Many types of kidney disease can damage the glomeruli, as well as secondary illnesses that cause kidney damage.

Symptoms

Glomerulonephritis signs and symptoms include:

  • blood in the urine
  • high blood pressure
  • swelling
  • urinating less than usual
  • inefficient filtering of waste from the blood
  • shortness of breath
  • possible flank pain

Treatment

A healthcare professional may conduct various tests to diagnose glomerulonephritis. These include:

Treatment will depend on the underlying cause, whether the condition is acute or chronic, and the severity of symptoms.

Painless blood in urine is the most common sign of bladder cancer. It also occurs as a result of renal cell and prostate cancers.

Symptoms

The most common symptom of bladder cancer is painless blood in a person’s urine. Other symptoms can include:

  • inability to empty the bladder completely
  • discomfort when urinating
  • high frequency of urinating

Prostate cancer often causes no symptoms in its early stages. When symptoms do occur, they can include:

  • blood in urine
  • frequent urination
  • dull pain in the lower pelvic area, or the thighs, lower back, or hips
  • trouble urinating
  • pain or burning when urinating
  • painful ejaculation
  • loss of appetite
  • weight loss
  • bone pain

Renal cell carcinoma may also cause no symptoms in its early stages. Symptoms can include:

  • blood in urine
  • a lump in the abdomen
  • loss of appetite
  • constant pain in a person’s side
  • weight loss
  • anemia

Treatment

Treatments for bladder cancer vary depending on the person and stage of the cancer. Options include:

Treatment for prostate cancer also varies depending on the person and stage of the disease. Treatment may include:

  • watchful waiting or active surveillance of the progression of cancer
  • surgery
  • chemotherapy
  • radiation therapy
  • targeted therapy
  • immunotherapy
  • bisphosphonate therapy

If renal cell carcinoma is within the kidneys, a person may require nephrectomy, or kidney removal surgery.

Healthcare professionals can discuss treatment decisions and can refer people to specialists if needed.

A person should contact a healthcare professional if blood appears in their urine. The cause is often harmless, but because it may indicate a severe condition, it is important to seek a diagnosis as soon as possible.

Various conditions can cause blood to occur in urine without pain. These may be harmless, but blood in the urine may also indicate a serious condition.

It is always best for a person to contact a healthcare professional for a diagnosis if they are experiencing blood in the urine without a clear cause.