What Can Cause Blood in Urine With No Pain?
You can have blood in your urine (hematuria) without any pain due to excessive exercise, trauma, or certain diseases. Since urine typically does not contain red blood cells, blood in your urine should prompt follow-up with a healthcare provider.
Healthcare providers divide hematuria into two categories:
Microscopic hematuria: Red blood cells are only visible under a microscope
Gross hematuria: The urine appears pink or red
Sometimes, hematuria has a simple explanation (e.g., exercise), while other types need further investigation and treatment. This article explains the potential causes of blood in the urine without pain.
Pramote Polyamate / Getty Images
Pramote Polyamate / Getty Images
Exercise
Working out, especially for long and intense periods, can affect your body’s ability to filter the blood in the kidneys. When this occurs, red blood cells can mix with urine (pee), and you may notice traces of blood when you urinate.
Symptoms
It is possible to have hematuria after exercise—or “exercise-induced hematuria.” Exercise-induced hematuria is often seen after intense, prolonged exercise, such as long-distance running or high-intensity interval training. Exercise-induced hematuria is typically painless.
Treatment
Healthcare providers don’t recommend treatment for exercise-induced hematuria and expect symptoms to resolve independently within 72 hours after the intense workout period ends. If you experience blood in your urine after 72 hours, follow up with a healthcare provider.
Trauma
Physical trauma, whether blunt or penetrating, with a direct hit to the organs of the urinary system (kidneys, renal pelvis, ureters, bladder, and urethra) can cause microscopic or gross hematuria. It is estimated that a little over 3% of people who experience physical trauma will have damage to some part of their kidneys (renal) system.
Symptoms
Depending on the type of trauma, symptoms might include pain or bruising to the flanks (on your side between your back and abdomen) and back. In severe cases, when people experience significant bleeding into the urine, they may experience additional symptoms associated with blood loss, such as elevated heart rate or low blood pressure.
Treatment
Identifying the site of injury is essential, so if a provider suspects you have renal system trauma, they will complete a computed tomography (CT) scan and laboratory blood analysis. Depending on your results, your healthcare provider will likely consider one of two treatment options:
Non-operative: For low-grade trauma, bed rest, serial labs (hematocrit and hemoglobin), and repeat imaging are often recommended. This watch-and-wait approach can start in the hospital and continue at home.
Operative: Operative management is not the preferred option but is often used in people with severe renal trauma, unstable vital signs, or significant loss of blood not responding to trauma resuscitation efforts.
Angiomyolipoma
Renal angiomyolipomas (AML) are the most common type of benign (not harmful) renal tumors. Renal AMLs are made of blood vessels, smooth muscles, and fatty tissue.
Symptoms
The majority of renal AMLs have no associated symptoms. They are often found incidentally during ultrasound or CT imaging.
Treatment
Most renal AMLs don’t require treatment unless the following symptoms or situations apply:
Symptoms like persistent pain
Multiple and/or large lesions
Weakened blood vessel walls within the AML, also called an aneurysm
Renal AML presence in women of childbearing age
High-risk occupations, such as commercial airline pilots
In these cases, discuss treatment options with your provider.
Kidney Diseases
There are many types of kidney diseases, the most common of which are discussed below.
Symptoms
Various kidney diseases can cause hematuria:
Urinary tract infections (UTIs): UTIs are often associated with lower abdominal pain, frequent urination, and burning with urination.
Kidney stones: Kidney stones are often associated with pain primarily in the back, nausea and/or vomiting, and fever or chills.
Hereditary diseases: Specific inherited diseases like polycystic kidney disease or Alport syndrome can cause hematuria. Polycystic kidney disease is associated with elevated blood pressure, pain in the back or side, and frequent bladder infections. Alport syndrome is also associated with high blood pressure but also includes swelling in ankles, legs, feet, and around the eyes.
Treatment
Treatment for each disease varies.
Urinary tract infections (UTIs): UTIs are often treated with a short (3-7 days) course of antibiotics. Healthcare providers recommend over-the-counter medications, such as Tylenol (acetaminophen) or Advil (ibuprofen), for pain management.
Kidney stones: Healthcare providers recommend drinking lots of fluid to help pass the stone from the kidney to the bladder to the outside world. They may prescribe you medications to help pass the stone and manage symptoms like nausea and pain. If you don’t pass the stone, a urologist may need to perform surgery to remove the stone using shock waves or a laser to break it into little fragments.
Hereditary diseases: Hereditary diseases do not have a cure. Treatment is primarily focused on managing symptoms.
Cancer
Hematuria is one of the early signs of bladder cancer. You can also experience hematuria if there is cancer in the kidney or the ureter. If you experience the symptoms below, follow up with a qualified healthcare provider for evaluation.
Symptoms
Symptoms of bladder cancer can include:
Blood in urine
Difficulty urinating or a weak urine stream
Increased urination urgency
Pain or burning with urination
Urinary frequency
Treatment
Treatment for bladder cancer depends on how advanced the cancer is (stage) and can include surgery, chemotherapy, radiation, immunotherapy, and other targeted therapies or a combination of these approaches. Treatments for other urinary tract cancers have similar options.
When to Contact a Healthcare Provider
Hematuria can be benign but should be evaluated by a qualified healthcare provider if:
It lasts more than 72 hours, even without other symptoms
You have pain in your lower abdomen, back, or flanks
You experience fever or chills
You experience frequent or painful urination
To identify the cause of the hematuria, a healthcare provider will likely:
Take a complete medical history
Perform a physical examination
Perform a urinalysis (a pee test)
If your healthcare provider can’t identify a clear cause for blood in your urine, they will order additional laboratory blood testing or imaging studies, such as ultrasound or CT scan.
Summary
Hematuria is the presence of red blood cells in the urine. There can be microscopic hematuria, where red blood cells are only visible under a microscope, or gross hematuria, where the urine appears reddish or pinkish. Hematuria can be benign, such as exercise-induced hematuria, or due to a urinary tract infection, kidney stones, genetic kidney diseases such as polycystic kidney disease, or trauma. Hematuria that lasts for more than 72 hours or has associated symptoms should be evaluated by a qualified healthcare provider, who can perform testing to identify the source of the hematuria and initiate appropriate treatment.
