What is the appropriate management for an asymptomatic female patient with leukocytes (white blood cells) in her urine?

Management of Asymptomatic Leukocyturia in Women

Do not treat asymptomatic leukocyturia in women—pyuria accompanying asymptomatic bacteriuria is not an indication for antimicrobial treatment. 1

Key Diagnostic Principle

The presence of leukocytes (white blood cells) in urine without symptoms does not warrant treatment, even when accompanied by bacteriuria. This is a critical distinction that prevents unnecessary antibiotic use and antimicrobial resistance. 1

Understanding the Clinical Context

Pyuria alone is not diagnostic of infection requiring treatment. The Infectious Diseases Society of America explicitly states that pyuria accompanying asymptomatic bacteriuria should not trigger antimicrobial therapy. 1 This recommendation carries an A-II strength rating, indicating strong evidence from well-designed studies. 1

Why Leukocytes Appear Without Infection

• Asymptomatic bacteriuria (ABU) commonly presents with pyuria but represents colonization rather than infection 1, 2
• Contamination during specimen collection frequently causes false-positive leukocyte findings 3
• Non-infectious inflammation can produce leukocyturia without requiring antibiotics 1

When NOT to Screen or Treat

The following groups should not be screened or treated for asymptomatic bacteriuria, even with leukocyturia present: 1

• Premenopausal, nonpregnant women (A-I recommendation) 1
• Diabetic women (A-I recommendation) 1
• Postmenopausal women (Strong recommendation) 1
• Elderly persons living in the community (A-II recommendation) 1
• Elderly institutionalized patients (A-I recommendation, Strong) 1
• Women with recurrent UTIs (Strong recommendation) 1
• Patients with spinal cord injury (A-II recommendation) 1
• Catheterized patients while catheter remains in place (A-I recommendation) 1

Critical Exceptions Requiring Treatment

Only two clinical scenarios warrant screening and treatment of asymptomatic bacteriuria: 1, 2

1. Pregnancy

• Screen all pregnant women with urine culture at least once in early pregnancy (A-I recommendation) 1
• Treat if positive with 3-7 days of antimicrobials or single-dose fosfomycin trometamol 1
• Perform periodic screening for recurrent bacteriuria following therapy 1

2. Before Urological Procedures Breaching the Mucosa

• Screen and treat before transurethral resection of prostate (A-I recommendation) 1
• Screen and treat before any urologic procedure with anticipated mucosal bleeding (A-III recommendation) 1
• Antimicrobial therapy should be initiated shortly before the procedure 1

Proper Diagnosis Requires Culture, Not Just Leukocytes

Leukocyte esterase testing alone is insufficient for diagnosis. 1 For asymptomatic women, true bacteriuria requires: 1

• Two consecutive voided urine specimens with isolation of the same bacterial strain
• Quantitative counts ≥10⁵ CFU/mL (B-II recommendation) 1
• A single positive leukocyte esterase test does not meet diagnostic criteria 1

Common Pitfalls to Avoid

Treating asymptomatic bacteriuria in women with recurrent UTIs is harmful. 1 This practice:

• Fosters antimicrobial resistance 1
• Increases the number of recurrent UTI episodes 1
• Eliminates potentially protective bacterial strains 1

Do not confuse asymptomatic leukocyturia with symptomatic infection. 4 In women with recurrent UTIs, an increase in leukocyturia of >150% from baseline has 90% sensitivity and 91% specificity for transition to symptomatic infection, but baseline leukocyturia alone does not indicate treatment. 4

Practical Management Algorithm

1. Confirm the patient is truly asymptomatic (no dysuria, frequency, urgency, suprapubic pain, fever) 1
2. Determine if patient is pregnant → If yes, obtain urine culture and treat if positive 1
3. Determine if urological procedure planned → If yes, screen and treat before procedure 1
4. If neither exception applies → No treatment regardless of leukocyte count 1
5. Educate patient that treatment is unnecessary and potentially harmful 1, 2

The evidence strongly supports watchful waiting over empiric treatment in asymptomatic women with leukocyturia, as treatment provides no benefit and increases antibiotic resistance. 1, 2