Definition of Leukocyte esterase:

Leukocyte esterase is a urine test to look for white blood cells and other signs associated with infection.

How the test is performed:

A clean catch urine sample is needed. See: Urine specimen - clean catch

How to prepare for the test:

No special preparation is necessary for this test.

How the test will feel:

The test will involve only normal urination, and there is no discomfort.

Why the test is performed:

Leukocyte esterase is a screening test used to detect a substance that suggests there are white blood cells in the urine, which may mean you have a urinary tract infection.

This test is part of the routine urine dipstick test. If this test is positive, the urine should be examined under a microscope for white blood cells and other abnormalities associated with infection.

Normal Values:

A negative test result is normal.

Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.

What abnormal results mean:

An abnormal result indicates a possible urinary tract infection.

What the risks are:

There are no risks.

Special considerations:

The following may create a false positive result:

• Vaginal secretions (such as blood or heavy mucus discharge)
• Trichomonas infection (such as trichomoniasis)

False negative tests can be caused by:

• High levels of protein
• High levels of vitamin C