Leukocyte Esterase
- Sample Type
- Standard
- Fasting
- No
- Unit
- n/a
Leukocyte Esterase (LE) is an enzyme produced by neutrophils. Its presence in the urine indicates pyuria (white blood cells in the urine), which is a hallmark of inflammation in the urinary tract. It is used as a primary screening tool for Urinary Tract Infections (UTI). When combined with a Nitrite test, it has a high negative predictive value for ruling out bacterial cystitis or pyelonephritis.
Why Context Matters
False positives can occur if the sample is contaminated with vaginal discharge or if Trichomonas is present. False negatives are common in cases of high glucose (glycosuria), high specific gravity, or if the patient is taking certain antibiotics like cephalexin or tetracycline, which interfere with the chemical reaction on the dipstick.
Lab ranges are statistical averages, not biological laws. "Normal" for a 20-year-old male isn't normal for a 60-year-old female.
Clinical References
Source-of-truth databases and clinical guidelines for Leukocyte Esterase:
Official Sources
Research & Guidelines
- PubMed: Leukocyte Esterase Clinical GuidelinesNCBI / PubMed
Related Indicators
Medically Reviewed by Dr. Binoy Babu, MBBS
Board Certified Doctor • 10+ Years Clinical Experience
Dr. Babu is a practicing physician dedicated to empowering patients with clear, actionable medical information. He founded 2opi to bridge the gap between complex lab reports and patient understanding, ensuring everyone has access to a reliable second opinion.
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