Hematuria is the presence of red blood cells 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.
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.
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.
Treatment for hematuria depends on the cause. If no serious condition is causing the hematuria, no treatment is necessary.
The National Kidney and Urologic Diseases Information Clearinghouse (NKUDIC) is a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).