You may have an infection.
A positive finding of the enzyme leukocyte esterase in urinalysis indicates the presence of white blood cells in the urine. This normally suggests inflammation of some sort, often from a urinary tract infection. A simple dipstick test as part of a urinalysis can detect the presence of this enzyme.
- Leukocyte esterase in urinalysis functions as a screening test. A negative result makes it unlikely an infection exists, thus making further testing of the urinary with a microscopic examination and urine culture for bacteria usually unnecessary.
- Although a urinary tract infection is the most common cause of leukocyte esterase in urinalysis some other and rarer causes for the positive result with a negative microorganism culture do exist. These include:
- Chlamydia
- Infection with a sexually transmitted microorganism called ureaplasma urealyticum
- Balanitis, a skin disease occurring at the head of the penis
- Cancer of the bladder
- Kidney stones
- Tuberculosis
- A foreign body in the urinary tract
- Glomerulonephritis, an inflammation of small blood vessels in the kidneys
- Prescription drugs such as corticosteroids
