11 causes of hematuria (blood in the urine)

Hematuria is when red blood cells are found in the urine. Hematuria can be macroscopic (also called gross hematuria), where blood is visible with the naked eye, or it can be microscopic, only visible when examined under a microscope. 

Here are 11 of the most common causes of hematuria: 

1. Urinary tract infections 

Urinary tract infections (UTIs) are the most common cause of blood in the urine. Since the urinary tract comprises the bladder, ureters and kidneys, a UTI is an infection anywhere in that system. A bladder infection is called cystitis, and a kidney infection is called pyelonephritis. 

UTIs are typically caused when bacteria on the skin of the perineum (the space between the rectum and genitals) track in through the urethra and then into the bladder. If a bladder infection goes undetected or untreated, the infection can continue to spread upward through the ureters and into the kidneys.  

Since women’s urethras are five times shorter than men’s, on average, women are much more prone to UTIs than men. 

In addition to hematuria, common UTI symptoms include burning with urination, urinary frequency and urinary urgency. Patients with pyelonephritis can also experience flank or back pain, fever and vomiting. 

Anyone with UTI symptoms should seek medical attention, as antibiotics are required to treat the infection and reduce the risk of serious complications, like a kidney infection. 

2. Urinary tract tumors 

Any patient with hematuria requires a medical workup to look for the source of the problem because, in some cases, hematuria is a sign of a tumor in the urinary tract.  

The most common urinary tract tumor is bladder cancer, which is more common in adults ages 65 and older, and more common in men than women. Cigarette smoking is another significant risk factor for bladder cancer, responsible for as many as 60% of cases. 

While patients with urinary tract tumors often fare well if diagnosed and treated early, they can be fatal if these tumors go undetected or untreated. Therefore, any patient with hematuria should seek prompt medical attention to determine the source of the blood. 

3. Kidney stones 

Kidney stones, called nephrolithiasis, are another cause of blood in the urine. Kidney stones lead to more than 500,000 emergency room visits in the U.S. each year. It’s estimated that 1 in 10 people in the U.S. will experience a kidney stone in their lifetime. 

In addition to macroscopic or microscopic hematuria, kidney stones can cause vomiting and severe unilateral flank pain that comes in waves (called colicky pain). 

Kidney stones are diagnosed on imaging — typically either ultrasound or CT scan. Stones that are less than 10 millimeters (about 0.39 in) in diameter usually pass on their own. In contrast, larger stones often require a surgical procedure to break them into smaller pieces so the patient can pass them. 

IV fluids and medication to alleviate vomiting and pain are often indicated for patients experiencing kidney stones. 

4. Prostatitis 

The prostate is a walnut-sized gland that sits between a man’s rectum and bladder and surrounds the top of the urethra. When the prostate becomes infected or inflamed (a condition called prostatitis), it can be a cause of hematuria in males. 

Other symptoms of prostatitis include frequent urination, urinary retention, fevers and pain in the back, lower abdomen or pelvis. Prostatitis is often treated with antibiotics and medication that decreases prostate inflammation. 

5. Pyelonephritis 

Pyelonephritis is a bacterial infection caused by complications related to a UTI when it spreads from the bladder to the kidneys. Symptoms include pain in your side, fever, nausea, vomiting, hematuria, urinary discomfort and increased frequency. Antibiotics are required to treat pyelonephritis.  

6. Cystitis 

Cystitis is a bacterial infection of the bladder, typically caused by a UTI, but it can also have other underlying causes. Symptoms are similar to UTI, including urinary frequency, pelvic pain, hematuria and fever. Cystitis also requires treatment with antibiotics.  

7. Sickle cell disease 

Sickle cell disease is a group of genetic conditions that impact the formation of red blood cells and hemoglobin, a protein that carries oxygen. Hematuria might be a sign of sickle cell disease. Speak to your healthcare provider if you have a family history of this condition.  

8. Endometriosis 

Endometriosis is typically a disorder of the tissue that lines the uterus but can rarely occur in the bladder as well. Symptoms may include pelvic pain, urinary urgency and hematuria. Treatment typically requires medication or surgery.  

9. Kidney disease 

Kidney disease is when the kidneys are damaged and cannot properly filter out blood, waste or water. Hematuria can be one symptom of kidney disease. If left untreated, some types of kidney disease can lead to kidney failure. If you are concerned about the health of your kidneys, it is best to speak to a healthcare provider.   

10. Cancer 

Hematuria can be the first sign of bladder cancer. If your urine is orange, pink or dark red, it is best to see a healthcare provider. But sometimes, cancer does not change the color of the urine; instead, the blood is identified during testing. 

11. Blood clotting disorder 

Blood clotting disorders impact the body’s ability to clot blood properly and are one cause of hematuria. The disorder may cause too many blood clots, or your body may have difficulty stopping bleeding after an injury. A blood clotting disorder may cause hematuria.  

Visit an urgent care for hematuria concerns 

Our urgent care partners are available 365 days a year to care for you and your loved ones, including care and testing if you have blood in your urine. We can test for UTIs and other conditions that can help determine the underlying cause of the bleeding. Just walk in or save your spot online at any of our conveniently located centers













Written by Sarah Thebarge, Physician Assistant