RBC urine test
Definition
The RBC urine test measures the number of red blood cells in a urine sample.
Alternative Names
Red blood cells in urine; Hematuria test; Urine - red blood cells
How the Test is Performed
A random sample of urine is collected. Random means that the sample is collected at any time either at the lab or at home.
A clean-catch urine sample is needed. The clean-catch method is used to prevent germs from the penis or vagina from getting into a urine sample. To collect your urine, your health care provider may give you a special clean-catch kit that contains a cleansing solution and sterile wipes. Follow instructions exactly so that the results are accurate.
How to Prepare for the Test
No special preparation is necessary for this test.
How the Test will Feel
The test involves only normal urination. There is no discomfort.
Why the Test is Performed
This test is done as part of a urinalysis test.
Normal Results
A normal result is 4 red blood cells per high power field (RBC/HPF) or less when the sample is examined under a microscope.
The example above is a common measurement for a result of this test. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test result.
What Abnormal Results Mean
A higher than normal number of RBCs in the urine may be due to:
- Kidney and other urinary tract problems, such as infection, or stones
- Kidney inflammation or injury
- Prostate problems
- Bladder, kidney, or urinary tract cancer
Risks
There are no risks with this test.
References
Krishnan A, Levin A. Laboratory assessment of kidney disease: glomerular filtration rate, urinalysis, and proteinuria. In: Yu ASL, Chertow GM, Luyckx VA, Marsden PA, Skorecki K, Taal MW, eds. Brenner and Rector's The Kidney. 11th ed. Philadelphia, PA: Elsevier; 2020:chap 23.
Lamb EJ, Jones GRD. Kidney function tests. In: Rifai N, Chiu RWK, Young I, Burnham CD, Wittwer CT, eds. Tietz Textbook of Laboratory Medicine. 7th ed. St Louis, MO: Elsevier; 2023:chap 34.
Riley RS, McPherson RA. Basic examination of urine. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 24th ed. Philadelphia, PA: Elsevier; 2022:chap 29.
Reviewed By: Jacob Berman, MD, MPH, Clinical Assistant Professor of Medicine, Division of General Internal Medicine, University of Washington School of Medicine, Seattle, WA. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
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