When blood is detected in your urine—whether it is visible to you or confirmed via urinalysis—you will likely feel compelled to seek out answers as to what might be causing it. This blog post will explore the causes of hematuria, including:

  • UTIs
  • Kidney stones
  • Trauma or injury
  • Enlarged prostate
  • Medications

The blog will also examine the medical conditions most commonly associated with hematuria, including: 

  • Glomerulonephritis 
  • Polycystic Kidney Disease (PKD) 
  • IgA Nephropathy
  • Bladder or kidney cancer
  • Inherited conditions 

We’ll conclude our “Causes of Hematuria” post by discussing when you should seek medical attention. Thank you for joining us on the FKP Kidney Health blog to learn about the causes of hematuria; we’re confident that you’ll learn a lot while you’re here.

Decoding Hematuria: Understanding Causes and Associated Medical Conditions


When you notice blood in your urine, or when your healthcare provider informs you that blood has been detected through a urinalysis, you may feel overwhelmed and full of questions. Specifically, you might be wondering why you have blood in your urine. What could be the cause? Determining the why aspect of hematuria is crucial because it can lead to a medical diagnosis that requires treatment—the cause, for example, could be a urinary tract infection, or a more serious condition known as Polycystic Kidney Disease (PKD).  

Blood in your urine is alarming, but learning more about why the blood is present will help you better understand hematuria, especially as it relates to your kidney health. The more you know about what causes hematuria, and the sooner you find out why you have blood in your urine, the more prepared you’ll feel to move forward with a care plan designed to keep you healthy.  

Common Causes of Blood in Urine

There are many common causes of blood in urine. Urology Care Foundation notes that blood in urine can even be caused by strenuous exercise: “If you see blood in your urine after an intense workout, you may have something called ‘exercise-induced hematuria.’ It is most common in runners, especially those running more than 10,000 meters (more than 6 miles). It can also occur after any prolonged, intense physical activity like high intensity interval training.”

If you have blood in your urine and you’re confident that is not exercise-induced, the blood might be appearing due to one of the following medical issues: 

  • Urinary Tract Infections (UTIs)

A UTI is defined as an infection in any part of the urinary system, but these infections most commonly form in the lower urinary tract and affect the bladder and urethra. Just like a pimple can bleed when picked or squeezed, blood can enter your urine when bacteria infiltrate the lining of your urethra or bladder and cause considerable irritation and inflammation. 

  • Kidney Stones

Kidney stones consist of numerous salts and minerals—substances in your urine that have crystallized over time. These hard deposits form in your kidneys and can affect any part of your urinary tract, including your bladder. Kidney stones vary in size, but the larger they are, the more difficult they are to pass. They can induce hematuria by producing scratches and abrasions along the urinary tract lining; getting lodged inside the tract, which impedes the regular flow of urine and puts increased pressure on the urinary tract lining; or fostering the development of bacteria in the urinary tract, potentially leading to a UTI. 

  • Trauma or Injury

Examples of a trauma or injury that can cause hematuria are a blunt force impact to the pelvic region while playing sports, or a fall from a ladder that results in a blow to your abdomen or back. Traumas and injuries can damage the kidneys or bladder, which can be what causes hematuria. If you have sustained an injury or experienced trauma near or around the kidney or bladder area, seek immediate medical attention so you can be evaluated and receive treatment for any potential internal injuries that can cause hematuria.  

  • Enlarged Prostate

The prostate is a walnut-shaped gland that serves as an integral part of the male reproductive system. An enlarged prostate, also known as benign prostatic hyperplasia (BPH), is common among older men. The prostate gland tends to increase in size as men age, which can put excess pressure on the urethra. Irritation and bleeding in the urinary tract will result in hematuria. 

  • Medications

Certain medications can affect how your urinary system functions. American Family Physician notes that patients on anticoagulant therapy (blood thinners) often present with gross hematuria. The antibiotic penicillin is also linked to hematuria, according to Mayo Clinic. Penicillin is often prescribed to treat bacterial infections—ear infections, strep, and pneumonia among them. 

Medical Conditions Associated with Hematuria:

There are quite a few medical conditions associated with hematuria. The following are the most common causes of hematuria. 

  • Glomerulonephritis

Glomerulonephritis is a group of diseases that directly affect the glomeruli, the filtering component of your kidneys. When the glomeruli become inflamed and scarred, your kidneys gradually lose their ability to remove metabolic waste and excess fluid from your blood. When your kidney health is compromised by glomerulonephritis, blood can make its way into your urine.

It’s important to identify the underlying cause of glomerulonephritis because this condition indicates that you may have a viral infection (such as hepatitis B, hepatitis C, or HIV), IgA nephropathy, lupus-related kidney inflammation, a bacterial infection, or it could also indicate that you have been exposed to certain toxins or medications that are damaging your kidneys.

  • Polycystic Kidney Disease (PKD)

Polycystic Kidney Disease (PKD) is a genetic disorder characterized by the development of noncancerous, fluid-filled cysts in the kidneys. These clusters can enlarge your kidneys and, over time, lead to impaired kidney function. Since the cysts vary in size, and some can grow to be quite large, these cysts can damage your kidneys and make it more likely for blood to leak into your urine.

If you have PKD, your doctor will create a comprehensive care plan for you so the disease can be appropriately managed and monitored. According to the PKD Foundation, “More than half of patients with PKD will have blood in their urine (hematuria) at some point. The urine may look pink, red, or brown. Passing small amounts of red blood cells in the urine that can only be seen under a microscope may also occur.” 

  • IgA Nephropathy

IgA nephropathy—also known as Berger’s Disease—is a kidney disorder and another medical condition closely associated with hematuria. Antibodies (IgA) build up in kidney tissue, causing your immune system to mistakenly attack its own tissues, including those located in the kidneys. This autoimmune disease causes inflammation and damages the glomeruli. When those tiny filtering units in the kidneys are impaired, hematuria may result. IgA nephropathy is the most common cause of glomerulonephritis.

Those who have been diagnosed with this disorder should seek immunosuppressive therapies to help manage this condition; there is no cure for IgA nephropathy, but according to the American Kidney Fund, certain medications can “slow the damage to your kidneys and delay or prevent kidney failure.” These medicines lower inflammation, control blood pressure, help remove extra fluid from your body, and lower your cholesterol in order to keep the disease in check.

  • Bladder or Kidney Cancer

Two of the most serious underlying medical conditions associated with a hematuria diagnosis are kidney cancer and bladder cancer. Kidney cancer and bladder cancer can both disrupt the normal functioning of your kidneys. You may not have any signs or symptoms of kidney cancer in its early stages, but over time, symptoms—including blood in your urine—may begin to appear.

Hematuria is also a common symptom of bladder cancer—either you will notice the blood, or it will be detected through a urinalysis. Both types of cancer require prompt medical attention, and your treatment options may include surgery, chemotherapy, and other targeted therapies that will be dependent on the stage of the cancer and other factors. Both cancers are treatable, but your prognosis will depend on early detection and timely intervention.

  • Inherited Conditions

Certain inherited conditions, such as sickle cell anemia or Alport syndrome, can also be what causes hematuria. Sickle cell disease affects the shape of your red blood cells, which are responsible for carrying oxygen throughout your body. Hematuria can develop among individuals diagnosed with sickle cell anemia because sickle-shaped cells can block blood flow to the kidneys. In the case of Alport syndrome, kidney function decreases over time because the disease attacks the glomeruli.

The progressive loss of kidney function makes hematuria one of the most common symptoms of Alport syndrome. If you have an inherited condition that affects your kidneys—or suspect that you do—it’s important to seek genetic counseling, which can provide insight into your condition and give your care team a more thorough understanding of your genetic makeup. They’ll use this information to tailor your treatment plan, and this will help you manage your condition in the interest of preventing further kidney damage.

Seeking Medical Evaluation

Any time you notice blood in your urine, reach out to your doctor. Regardless of the color, quantity, and frequency, the presence of blood in your urine must be addressed. No matter what causes hematuria, there’s no good excuse to ignore it—blood in your urine really is a “red flag.” Prompt medical attention can ensure a thorough evaluation, timely diagnosis, and appropriate intervention; if you have kidney or bladder cancer, immediate medical care can even save your life.

Proactive communication with your healthcare provider will serve you well—you’ll gain clarity as it relates to a possible underlying condition, and clarity can go a long way in making you feel in control of your health and well-being.

Empowering Individuals Through Knowledge

This blog discussed the causes of hematuria—from UTIs and kidney stones to associated medical conditions such as glomerulonephritis and kidney cancer. Taking a proactive approach to your kidney health involves staying informed, seeking timely medical attention, and collaborating with your doctor or nephrologist to receive the comprehensive care you need. 

We hope this FKP Kidney Health blog post helped you gain a better sense of the causes of hematuria, and we welcome you to read our next post, “Unraveling the Enigma: Recognizing Symptoms and Diagnosing Hematuria.” It will discuss the symptoms commonly associated with hematuria as well as the diagnostic tests that doctors rely on to identify underlying health conditions. We really do believe that knowledge is power, and we look forward to continuing to support you along your journey toward achieving optimal kidney health.