Leukocytes, commonly known as white blood cells, are a vital part of the body’s immune system. These specialized cells circulate throughout the bloodstream, identifying and neutralizing foreign invaders like bacteria and viruses. They act as the body’s primary defenders, combating infections and addressing inflammation.
Understanding Leukocytes in Urine
When leukocytes are detected in a urine sample, it signals infection or inflammation within the urinary tract or reproductive system. This finding, often identified through a routine urinalysis, indicates an immune response. A dipstick test can initially detect an enzyme released by these cells, known as leukocyte esterase, suggesting their presence. Microscopic examination then confirms the number of white blood cells.
The presence of leukocytes in urine is a non-specific sign, meaning it points to an underlying issue but does not pinpoint the exact cause. Healthy individuals typically have very few leukocytes in their urine, generally less than 5 white blood cells per high-powered field. An elevated count suggests further investigation is necessary to determine the specific source of the immune activity. This finding serves as an important indicator that something within the genitourinary system requires attention.
Leukocytes and Sexually Transmitted Infections
Sexually transmitted infections (STIs) can lead to leukocytes in urine. These infections cause inflammation in the genital and urinary tracts, prompting white blood cells to the affected area. For instance, Chlamydia trachomatis and Neisseria gonorrhoeae, common bacterial STIs, can infect the urethra and reproductive organs, releasing leukocytes into the urine.
Trichomoniasis, caused by Trichomonas vaginalis, is another STI known to induce inflammation in the urogenital tract, increasing white blood cell counts in urine. Even some viral STIs, such as herpes simplex virus (HSV) and human papillomavirus (HPV), can cause inflammation leading to leukocytes in urine, sometimes without bacteria, a condition known as sterile pyuria. While STIs are a possible cause, the detection of leukocytes in urine is not solely indicative of an STI, as many other conditions can also trigger this immune response.
Other Causes of Leukocytes in Urine
Beyond sexually transmitted infections, numerous other conditions can cause leukocytes to appear in urine. Urinary tract infections (UTIs) are a common reason for elevated white blood cell counts, as bacteria multiplying in the urinary tract trigger an immune response. Kidney infections, also known as pyelonephritis, represent a more serious form of UTI where bacteria ascend to the kidneys, leading to inflammation and leukocyte presence.
Kidney stones can also cause leukocytes in urine by irritating the urinary tract lining and potentially creating blockages that increase the risk of infection. Vaginal infections, such as bacterial vaginosis or yeast infections, can sometimes contaminate a urine sample, leading to a false positive for leukocytes, or cause inflammation affecting the urinary tract. Conditions like interstitial cystitis, which involves chronic bladder inflammation not caused by infection, can also result in leukocytes in urine. Certain medications, like nonsteroidal anti-inflammatory drugs (NSAIDs) or some antibiotics, and even strenuous exercise, can temporarily increase leukocyte levels.
What to Do When Leukocytes Are Detected
If a urine test indicates leukocytes, consulting a healthcare professional is the appropriate next step. This finding necessitates further medical evaluation to identify the underlying cause and determine the correct course of action. Self-diagnosis or attempting self-treatment based solely on leukocyte presence is not advisable, as causes vary widely and require specific treatments.
A doctor will likely recommend additional diagnostic tests to pinpoint the issue. These may include a urine culture to identify specific bacteria or other pathogens, or targeted STI tests if an STI is suspected. Imaging studies, such as an ultrasound or CT scan, might be ordered if kidney stones or structural issues are a concern. An accurate diagnosis is necessary for effective treatment and managing any potential health conditions.