Leukocytes in urine (white blood cells in urine): what it means
What it measures
This test looks for leukocytes (white blood cells), which are part of the body's immune system, in the urine as part of a routine urinalysis. It is checked two ways: a dipstick that detects leukocyte esterase — per MedlinePlus, "a substance that suggests there are white blood cells in the urine" — and, when needed, a microscopic look at the urine to count white blood cells directly.
Why it’s ordered
It screens for white blood cells in the urine, which can be a sign of infection or inflammation somewhere in the urinary tract, and is often ordered as part of a general urinalysis or when a urinary tract infection (UTI) is suspected. Per MedlinePlus, if the leukocyte esterase test is positive, "the urine should be examined under a microscope for white blood cells and other signs that point to an infection"; a urinalysis itself is "often done to check for a urinary tract infection, kidney problems, or diabetes." Providers weigh this result alongside the rest of the urinalysis rather than on its own.
General reference range
On the dipstick (leukocyte esterase) portion, MedlinePlus states that "A negative test result is normal." When urine is examined under a microscope, only a small number of white blood cells is generally expected. These are general reference points only: normal ranges and the way a result is reported vary by laboratory, by the method used, and can differ by age, sex, and individual circumstances. The reference range printed on your own lab report is what applies to you, and a value on its own is not a diagnosis.
If it’s high
A positive or elevated result is non-specific and should be read cautiously. Per MedlinePlus, "An abnormal result indicates a possible urinary tract infection," and "White blood cells in urine may also mean you have a UTI." White blood cells in the urine can also be seen with other kinds of infection or inflammation in the urinary tract. Some things can distort the dipstick reading: trichomonas infection and vaginal secretions can cause false-positive results, while a high level of protein or vitamin C can cause false negatives. This is a general list of possible associations, not a complete list and not a diagnosis — your provider interprets it together with your other results, symptoms, and history.
If it’s low
Leukocytes are not typically reported as "low." A negative dipstick result (no leukocyte esterase detected) is considered normal, and few or no white blood cells on microscopy is the expected finding. A urinalysis has several parts, and your provider interprets white blood cells together with the rest of your results to understand what they mean in your situation. This is general information, not medical advice.
A result is not a diagnosis
Reference ranges vary by laboratory, age, sex, and method — the range on your own report is what applies to you. A single value out of range doesn’t confirm any condition; your clinician interprets it alongside your symptoms, history, and other results. This page is general information, not medical advice.
Frequently asked
- What does the Leukocytes in urine (white blood cells in urine) test measure?
- This test looks for leukocytes (white blood cells), which are part of the body's immune system, in the urine as part of a routine urinalysis. It is checked two ways: a dipstick that detects leukocyte esterase — per MedlinePlus, "a substance that suggests there are white blood cells in the urine" — and, when needed, a microscopic look at the urine to count white blood cells directly.
- What is a normal Leukocytes in urine (white blood cells in urine) range?
- On the dipstick (leukocyte esterase) portion, MedlinePlus states that "A negative test result is normal." When urine is examined under a microscope, only a small number of white blood cells is generally expected. These are general reference points only: normal ranges and the way a result is reported vary by laboratory, by the method used, and can differ by age, sex, and individual circumstances. The reference range printed on your own lab report is what applies to you, and a value on its own is not a diagnosis.
- What does a high result mean?
- A positive or elevated result is non-specific and should be read cautiously. Per MedlinePlus, "An abnormal result indicates a possible urinary tract infection," and "White blood cells in urine may also mean you have a UTI." White blood cells in the urine can also be seen with other kinds of infection or inflammation in the urinary tract. Some things can distort the dipstick reading: trichomonas infection and vaginal secretions can cause false-positive results, while a high level of protein or vitamin C can cause false negatives. This is a general list of possible associations, not a complete list and not a diagnosis — your provider interprets it together with your other results, symptoms, and history.
- What does a low result mean?
- Leukocytes are not typically reported as "low." A negative dipstick result (no leukocyte esterase detected) is considered normal, and few or no white blood cells on microscopy is the expected finding. A urinalysis has several parts, and your provider interprets white blood cells together with the rest of your results to understand what they mean in your situation. This is general information, not medical advice.
Other lab tests
Sources
General reference, not medical advice, and not a substitute for your clinician. Lab reference ranges and interpretation depend on the laboratory and on your individual situation — discuss your results with a licensed healthcare professional.