Blood in urine (Hematuria): Symptoms, Causes, Diagnosis, Treatment & Prevention

Hematuria, or blood in the urine, can be frightening. The reason is usually harmless. However, blood in the urine might potentially indicate a serious illness.

It's known as gross hematuria if the blood is visible. Microscopic hematuria is the term for blood that is invisible to the human eye. When a lab tests the pee, the amount is so little that it can only be detected under a microscope. In any case, determining the cause of the bleeding is important. The cause determines the course of treatment.

Urinary tract infections, intense activity, and chronic renal disease are just a few of the numerous causes of blood in the urine. 

Also Read: Urinary Tract Infection (UTI): Causes, Symptoms, Risk factors, Diagnosis, Treatment & Prevention

What is hematuria, or blood in the urine?

The medical term for the presence of blood cells in your urine (pee) is hematuria (hee-muh-TOOR-ee-uh).

It’s fairly typical for blood to be in your pee. However, since it doesn't always cause your urine to appear pink or crimson, you might not even be aware of it. Sometimes, a urine test is how medical professionals find the tiny quantity of blood in your urine that you are unable to notice.

However, it could be an indication that something is wrong if you notice that your urine appears pink or scarlet, or if you experience other signs of hematuria. You ought to get in touch with a medical professional.

What types of hematuria are there?

Blood in urine is classified by medical professionals as:

• Hematuria is disgusting. This occurs when enough blood is in your urine to be seen with the naked eye. Toilet water may become bright red or pastel pink as a result of it.

• Small-scale hematuria. If you have microscopic hematuria, also known as microhematuria, you have blood in your urine, but not enough to be seen with the naked eye. To observe it, a microscope is required.

• Hematuria from dipstick. When a dipstick changes color due to oxidation (exposure to oxygen), it is known as dipstick hematuria. Dipsticks are thin paper or plastic strips with chemical patches on them. If you have specific substances in your urine, the chemicals change color.

The false-positive rate for dipstick testing is rather high. When the dipstick test indicates that you have blood in your urine when you don't, this is known as a false-positive rate. Providers must perform a microscopic urinalysis to confirm dipstick hematuria.

 

Symptoms:

Urine containing blood may appear cola-colored, pink, or red. Urine changes color due to red blood cells. Urine can become crimson with just a tiny bit of blood.

Usually, the bleeding isn't painful. However, it might be painful if blood clots pass through the urine.
If you experience other symptoms, these could include:

• Urinating more frequently than normal

• Dysuria is pain or burning when urinating.

An intense urge to urinate immediately (urinary urgency)
You might also experience additional related symptoms, such as:

• Vomiting and feeling queasy

• Fever chills

• Pain in the lower back

• Pain in the abdomen

• Pain right above your hips on both sides of your lower back (flank pain)

Causes: 

Blood cells seeping into urine from the kidneys or other urinary tract components are the cause of this illness. This leak can occur due to a variety of issues, such as:

• Infections of the urinary tract (UTIs). These occur when bacteria enter the urethra, the canal that pee exits the body through. In the bladder, the bacteria then multiply. Urine may appear red, pink, or brown due to bleeding caused by UTIs. You can also experience a persistent, intense urge to urinate when you have a UTI. While urinating, you can experience pain and burning. It's also possible that your urine smells strong.

• Infection of the kidney. Another name for this type of UTI is pyelonephritis. When bacteria from the circulation invade the kidneys, kidney infections may result. Bacteria can also infect the kidneys through the ureters, which are two tubes that link the kidneys to the bladder. Urine-related symptoms from kidney infections can be similar to those from other UTIs. However, they are more likely to result in fever and groin, side, or back pain.
• Kidney or bladder stone. Urine minerals have the potential to crystallize on the kidney or bladder walls. The crystals may eventually grow into tiny, hard stones.Frequently, the stones cause no pain. However, if they obstruct the body or exit through the urine, they can cause severe pain. In addition to bleeding that is only visible in a laboratory setting, bladder or kidney stones can result in blood in the urine that is visible to the unaided eye.

• Enlarged prostate. The prostate gland encircles the upper portion of the urethra and is located directly beneath the bladder. As one approaches middle age, it frequently gets larger. The urethra is then compressed, partially obstructing the urine flow. Blood in the urine, difficulty urinating, or a persistent or urgent urge to urinate are all symptoms of an enlarged prostate. The same symptoms can be caused by prostatitis, an infection of the prostate.

• Kidney disease. A common sign of glomerulonephritis, a kidney disease, is blood in the urine that is only seen in a laboratory. This illness causes inflammation in the kidneys' small filters, which filter waste from the blood. Diabetes and other conditions that impact the entire body may include glomerulonephritis. Or it may occur spontaneously.

• Cancer. If there is visible blood in the pee, it could indicate advanced prostate, bladder, or kidney cancer. It's possible that some malignancies won't show symptoms sooner, when therapies could be more effective.

• Inherited diseases. Blood in urine can be caused by sickle cell anemia, a hereditary disorder that damages red blood cells. The blood cells may be too small to notice or they may be visible. Blood in the urine can potentially be a symptom of Alport syndrome, a disorder that damages small blood arteries in the kidneys.

• Kidney injury. Urine may contain blood if the kidneys have been struck or otherwise injured in an accident or contact sport.

• Medications. Blood in urine is associated with the antibiotic penicillin and the anti-cancer medication cyclophosphamide (Cytoxan). Blood in urine is also linked to medications that prevent blood clots. These include medications like aspirin, which reduces pain, that prevents platelets, which are blood cells, from adhering to one another. Heparin and other blood-thinning medications could possibly be the cause.

• Hard exercise. After participating in contact sports like football, blood in the urine is possible. It might be connected to bladder damage from being struck. Long-distance sports like marathon running can also result in blood in the urine, however the cause is less obvious. It could be related to bladder damage or other non-injury-related causes. Blood in the urine from vigorous exercise may disappear on its own after a week. Don't assume that blood in your urine after working out is the result of your exercise. Consult your physician.

Hematuria's cause is frequently unknown.

Risk factors:

Red blood cells in the urine can occur in almost everybody. Children and teenagers are included in this. The following are some factors that may increase the likelihood of blood in the urine:

• Age. An enlarged prostate gland may increase the risk of hematuria in middle-aged and older men. After the age of fifty, there may be an increased chance of some malignancies that can result in blood in the urine.

• Infection in the urinary tract. This is one of the main reasons why children's urine contains blood.

• Family history. If one or more family members have had renal illness, the likelihood of blood in the urine may increase.

• Certain medications. Antibiotics, blood thinners, and some painkillers can increase the risk of blood in the urine.

• Hard exercise. One term for hematuria is "marathon runner's hematuria." Sports involving contact can also increase the risk.

How is the diagnosis of hematuria made?

A medical professional will go over your medical history, ask about any other symptoms, and do a physical examination, which can involve a digital rectal exam or pelvic exam.To help confirm a diagnosis of hematuria, they could also suggest further testing.

To diagnose hematuria, what tests will be performed?

To aid in the diagnosis of hematuria, a medical professional could suggest the following tests:

• Urine analysis. When you urinate in a designated cup, a healthcare professional examines it to seek indications of hematuria-causing disorders.

• Culturing of urine. A healthcare professional looks for indications of infection after you urinate in a designated cup.

• Cytology of urine. A healthcare professional examines your urine in a specialized cup to look for any cells that seem abnormal.

• Cystoscopy. To inspect your urethra and bladder, a healthcare professional inserts a tiny camera, known as a cystoscope, through your urethra and into your bladder.

• Imaging tests. Images of your urinary system as well as other organs and structures are produced by noninvasive imaging procedures including an MRI, CT scan, and ultrasound.

Treatment:

The cause of blood in the urine determines the course of treatment. Treatment could include:

• Using antibiotics to treat an infection of the urinary system.
• Attempting to reduce an enlarged prostate with a prescription medication.
• Undergoing a procedure that breaks up kidney or bladder stones using sound waves.
• Sometimes there is no need for treatment.

After receiving therapy, follow up with your provider to ensure that your urine is free of blood.

Prevention:

Can we prevent hematuria?

Not every cause of hematuria may be avoided. However, you can stop some of the causes by:

• Drinking a lot of water every day

• Urinating both before and after engaging in sexual activity

• Keeping your weight within a healthy range

• Restricting consumption of foods heavy in animal proteins, sugar, and sodium (salt)

• Quitting smoking

• Reducing your exposure to potentially harmful substances or chemicals

References:

• American Kidney Fund. Blood in Urine (Hematuria): Causes and Treatment (https://www.kidneyfund.org/all-about-kidneys/other-kidney-problems/blood-urine-hematuria). Last updated 4/12/2022. Accessed 1/13/2025.

• Sorensen M, Hehemann MC, Haider MA. Hematuria. In: Papadakis MA, Rabow MW, McQuaid KR, et al., eds. Current Medical Diagnosis & Treatment 2025. McGraw-Hill Education; 2025.

• Isolated hematuria. Merck Manual Professional Version. https://www.merckmanuals.com/professional/genitourinary-disorders/symptoms-of-genitourinary-disorders/isolated-hematuria. Accessed Nov. 4, 2022.

• National Institute of Diabetes and Digestive and Kidney Diseases (U.S.). Hematuria (Blood in the Urine) (https://www.niddk.nih.gov/health-information/urologic-diseases/hematuria-blood-urine). Last reviewed 10/2022. Accessed 1/13/2025.

• Urinary tract infection. Centers for Disease Control and Prevention. https://www.cdc.gov/antibiotic-use/uti.html. Accessed Nov. 17, 2022.

• Wein AJ, et al., eds. Benign prostatic hyperplasia: Etiology, pathophysiology, epidemiology, and natural history. In: Campbell-Walsh-Wein Urology. 12th ed. Elsevier; 2021. https://www.clinicalkey.com. Accessed Nov. 29, 2022.

• Cheng L, et al., eds. Urine cytology. In: Urologic Surgical Pathology. 4th ed. Elsevier; 2020. https://www.clinicalkey.com. Accessed Dec. 8, 2022.

• Boyer O. Evaluation of gross hematuria in children. https://www.uptodate.com/contents/search. Accessed Nov. 8, 2022.

• Bladder cancer risk factors. American Cancer Society. https://www.cancer.org/cancer/bladder-cancer/causes-risks-prevention/risk-factors.html. Accessed Nov. 17, 2022.

• Medical student curriculum: Hematuria. American Urological Association. https://www.auanet.org/meetings-and-education/for-medical-students/medical-students-curriculum/hematuria. Accessed Nov. 4, 2022.