What Causes Hematuria and How Is It Diagnosed?

Hematuria is the presence of red blood cells (RBCs) in the urine.

In microscopic hematuria, the urine appears normal to the naked eye, but examination with a microscope shows a high number of RBCs.

Gross hematuria can be seen with the naked eye-the urine is red or the color of cola.

What causes hematuria?

Several conditions can cause hematuria, most of them not serious. For example, exercise may cause hematuria that goes away in 24 hours. Many people have hematuria without any other related problems. Often no specific cause can be found. But because hematuria may be the result of a tumor or other serious problem, a doctor should be consulted.

How is hematuria diagnosed?

To find the cause of hematuria, or to rule out certain causes, the doctor may order a series of tests, including urinalysis, blood tests, kidney imaging studies, and cystoscopic examination.

•     Urinalysis is the examination of urine for various cells and chemicals. In addition to finding RBCs, the doctor may find white blood cells that signal a urinary tract infection or casts, which are groups of cells molded together in the shape of the kidneys' tiny filtering tubes, that signal kidney disease. Excessive protein in the urine also signals kidney disease.
•     Blood tests may reveal kidney disease if the blood contains high levels of wastes that the kidneys are supposed to remove.
•     Kidney imaging studies include ultrasound, computerized tomography (CT) scan, or intravenous pyelogram (IVP). An IVP is an x ray of the urinary tract. Imaging studies may reveal a tumor, a kidney or bladder stone, an enlarged prostate, or other blockage to the normal flow of urine.
•     A cystoscope can be used to take pictures of the inside of the bladder. It has a tiny camera at the end of a thin tube, which is inserted through the urethra. A cystoscope may provide a better view of a tumor or bladder stone than can be seen in an IVP.

How is hematuria treated?

Treatment for hematuria depends on the cause. If no serious condition is causing the hematuria, no treatment is necessary.

For more information

American Kidney Fund
6110 Executive Boulevard, Suite 1010
Rockville, MD 20852 Phone: 1-800-638-8299 or 301-881-3052
Email: [email protected]

National Kidney Foundation, Inc.
30 East 33rd Street
New York, NY 10016
Phone: 1-800-622-9010 or 212-889-2210

Adapted from "Hematuria: Blood in the Urine," a publication of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), National Institutes of Health (NIH).

By National Institutes of Health

The National Institutes of Health, a part of the U.S. Department of Health and Human Services, is the nation's medical research agency — making important discoveries that improve health and save lives. NIH is the largest single source of financing for medical research in the world, seeking new ways to cure disease, alleviate suffering and prevent illness. By providing the evidence base for health decisions by individuals and their clinicians, NIH is empowering Americans to embrace healthy living through informed decision-making. NIH is made up of 27 institutes and centers, each with a specific research agenda, focusing on stages of life, like aging or child health, or particular diseases or body systems.