The presence of “large leukocytes” in urine, also known as white blood cells, often signals the body is actively responding to an underlying condition. Leukocytes are a fundamental part of the body’s immune system, defending against infections and foreign invaders. An elevated number in a urine sample most commonly indicates inflammation or infection within the urinary system.
Understanding Leukocytes in Urine
A urine test indicating “large leukocytes” refers to an elevated concentration of white blood cells in the urine sample. Healthy individuals typically have very few leukocytes in their urine, usually zero to five white blood cells per high-powered field (HPF) when examined microscopically. Detection occurs through urinalysis, which involves visual inspection for cloudiness, a dipstick test for leukocyte esterase (an enzyme found in some white blood cells), and a microscopic examination.
Leukocytes are produced in the bone marrow and distributed throughout the bloodstream and tissues to combat pathogens like bacteria, viruses, and other harmful substances. Their primary function is to identify and neutralize threats, initiating an immune response wherever an infection or inflammation is present. A substantial presence of these cells in urine suggests immune system activation in the urinary tract or adjacent areas, prompting further investigation to pinpoint the specific cause.
Common Reasons for Leukocytes in Urine
The most frequent cause for an elevated leukocyte count in urine is a urinary tract infection (UTI). These infections occur when bacteria enter and multiply within any part of the urinary system, including the urethra, bladder, or kidneys, leading to an inflammatory response. The body dispatches leukocytes to the site of infection to fight off these invading bacteria, resulting in their presence in the urine.
Kidney infections, medically termed pyelonephritis, are a more serious UTI where bacteria ascend from the lower urinary tract to the kidneys. This infection often leads to a higher concentration of leukocytes due to the body’s intense immune reaction within the kidney tissue. Kidney stones can also contribute to leukocytes in urine by causing irritation, inflammation, or by creating blockages that impede urine flow and potentially lead to secondary infections.
Inflammation within the urinary tract, even without a bacterial infection, can also cause leukocytes to appear. Examples include cystitis (bladder inflammation) or urethritis (inflammation of the urethra), which may result in an increased leukocyte count. Urethritis can stem from sexually transmitted infections (STIs) like chlamydia or gonorrhea, or from non-infectious irritants. Additionally, conditions affecting nearby organs, such as vaginitis in women or prostatitis in men, can cause leukocytes to spill into the urine sample. Less common causes include interstitial cystitis, certain medications, and in rare instances, tumors in the pelvic area.
When to Seek Medical Advice and What to Expect
Consult a healthcare professional if a urine test indicates large leukocytes. Self-diagnosis is not recommended, as the underlying cause requires accurate medical assessment. A doctor will typically begin with a physical examination and may order additional urine tests to gather more specific information.
Further urine analysis often includes a urine culture, which helps identify the specific type of bacteria present and guides appropriate antibiotic treatment. Blood tests may also be conducted to check for signs of systemic infection or inflammation. Depending on the suspected cause, imaging studies might be necessary. These can include an ultrasound for kidneys and bladder, a CT scan for detailed urinary tract views, or an MRI for soft tissue visualization.
Addressing the Underlying Cause
Treatment for an elevated leukocyte count in urine depends on the specific underlying cause identified through diagnostic testing. If a bacterial infection, such as a UTI or kidney infection, is confirmed, antibiotics are typically prescribed to eliminate the bacteria. It is important to complete the full course of antibiotics as directed, even if symptoms improve, to ensure the infection is fully resolved.
For kidney stones, treatment may involve pain management, increased fluid intake to help pass smaller stones, or medical procedures such as sound wave therapy or surgery for larger stones that cause blockages or severe discomfort. If inflammation without bacterial infection is the cause, anti-inflammatory medications might be recommended. Adhering to medical advice is important for effective treatment and to prevent potential complications, such as the infection spreading or leading to kidney damage.