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. If needed, the health care provider may ask you to collect your urine at home over 24 hours. Your provider will tell you how to do this.

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, the 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:

• Bladder, kidney, or urinary tract cancer
• Kidney and other urinary tract problems, such as infection, or stones
• Kidney injury
• Prostate problems

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, ed. Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. 6th ed. St Louis, MO: Elsevier; 2018:chap 32.

Riley RS, McPherson RA. Basic examination of urine. In: McPherson RA, Pincus MR, eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 23rd ed. St Louis, MO: Elsevier; 2017:chap 28.