What should I do if there are white blood cells in my urine?
If white blood cells (leukocytes) are detected in the urine—a finding known as pyuria—it indicates inflammation or infection somewhere along the urinary tract. This is not a diagnosis in itself but rather a laboratory clue that warrants further clinical evaluation. Common causes include urinary tract infections (UTIs), such as cystitis or pyelonephritis; however, non-infectious conditions like interstitial cystitis, urethritis (e.g., due to sexually transmitted infections), renal stones, glomerulonephritis, or even systemic inflammatory conditions (e.g., lupus nephritis or vasculitis) can also produce pyuria.
Initial assessment should include a detailed history—focusing on symptoms such as dysuria, frequency, urgency, suprapubic or flank pain, fever, or hematuria—as well as a physical examination and urinalysis with microscopy. A urine culture and sensitivity test is essential if infection is suspected, particularly before initiating antibiotic therapy. In cases of persistent or sterile pyuria (white blood cells without bacterial growth), additional investigations may be needed, such as imaging (e.g., renal ultrasound or CT urogram), cystoscopy, or serologic testing depending on clinical context.
Treatment depends entirely on the underlying cause. For uncomplicated lower UTIs in otherwise healthy adults, first-line antibiotics such as nitrofurantoin, fosfomycin, or trimethoprim-sulfamethoxazole (where local resistance patterns permit) are appropriate. Complicated or upper tract infections may require broader-spectrum agents and sometimes intravenous therapy. Non-infectious causes require targeted management—for example, immunosuppression for glomerulonephritis or behavioral and pharmacologic interventions for interstitial cystitis.
It’s important to avoid overinterpreting isolated pyuria without correlating it with clinical signs, symptoms, and other laboratory findings. Asymptomatic pyuria—especially in older adults or individuals with indwelling catheters—may reflect colonization rather than active disease and does not routinely require treatment. Always consult a qualified healthcare provider for personalized evaluation and management.