Urine Leukocyte Esterase
This dipstick test detects leukocyte esterase, an enzyme released by white blood cells. Its presence suggests white blood cells are in the urine, a sign of inflammation.
White blood cells gather where the body is responding to irritation or infection, so this test helps flag inflammation in the urinary tract. Combined with the nitrite test and your symptoms, it helps your clinician judge whether a urinary tract infection is likely. It's a useful screening clue that guides whether further testing is needed.
A positive result suggests white blood cells are present, pointing to inflammation that a clinician may link to a urinary tract infection or other irritation, often confirmed with microscopy or a culture.
A negative result means little or no leukocyte esterase was detected, generally a reassuring sign of no significant urinary tract inflammation.
Negative is the expected result. A positive finding, especially with symptoms or a positive nitrite test, is interpreted by a clinician who may confirm with microscopy or a urine culture.
Sources
Educational context only, not medical advice or a diagnosis. Reference ranges vary by lab, age and sex; always discuss your results with a clinician.