How is asymptomatic bacteruria typically managed?

Management of Asymptomatic Bacteriuria

Asymptomatic bacteriuria should NOT be treated in most clinical situations—the only clear exceptions are pregnant women and patients undergoing endoscopic urologic procedures that breach the mucosal lining. 1

When NOT to Screen or Treat (Strong Recommendations)

The following populations should not be screened for or treated for asymptomatic bacteriuria, as treatment provides no benefit and causes harm:

• Healthy premenopausal, nonpregnant women 1
• Healthy postmenopausal women 1
• Patients with diabetes (both men and women) 1
• Older persons living in the community 1
• Elderly, institutionalized patients 1
• Patients with spinal cord injury 1
• Patients with short-term indwelling urethral catheters (<30 days) 1
• Patients with long-term indwelling catheters 1
• Renal transplant recipients (>1 month post-transplant) 1
• Non-renal solid organ transplant recipients 1
• Patients with implanted urologic devices (artificial sphincters, penile prostheses) 1
• Patients undergoing non-urologic surgeries (including orthopedic arthroplasty, cardiac, vascular, general abdominal surgery) 2, 3

Critical Point About Pyuria

Pyuria accompanying asymptomatic bacteriuria is NOT an indication for antimicrobial treatment. 1 The presence of white blood cells in urine does not change the management approach—if the patient has no symptoms, do not treat regardless of pyuria. 4

When TO Screen and Treat (Strong Recommendations)

1. Pregnant Women

• Screen all pregnant women with urine culture at least once in early pregnancy 1
• Treat if positive with 4-7 days of antimicrobial therapy (not shorter courses) 1
• Perform periodic screening for recurrent bacteriuria following therapy 1
• This is the only non-surgical population where treatment reduces morbidity (specifically pyelonephritis) 5, 6

2. Endoscopic Urologic Procedures with Mucosal Trauma

Screen and treat before procedures that breach the mucosal lining, including: 1

• Transurethral resection of prostate (TURP)
• Transurethral resection of bladder tumor (TURBT)
• Ureteroscopy with lithotripsy
• Percutaneous stone surgery

Treatment protocol for these procedures: 1

• Obtain preoperative urine culture for targeted therapy (not empiric)
• Use short-course antimicrobials (1-2 doses only), not prolonged courses
• Initiate antibiotics 30-60 minutes before the procedure
• Do not continue antibiotics after the procedure unless an indwelling catheter remains

The evidence is compelling: Untreated asymptomatic bacteriuria before TURP carries a 13% risk of postoperative sepsis versus 0-4.5% with treatment. 1, 3 Four patients developed bacteremia in the untreated group versus zero in the treated group in randomized trials. 1

Low-Risk Urologic Procedures (No Treatment Needed)

Do not screen or treat before: 1, 3

• Diagnostic cystoscopy without biopsy
• Simple catheter removal or exchange
• Removal of ureteral stents

Special Populations Requiring Careful Assessment

Older Adults with Delirium or Falls

Do not treat bacteriuria in cognitively/functionally impaired older adults who present with delirium or falls. 1 Instead:

• Assess for other causes of delirium (medications, metabolic derangements, hypoxia, infection elsewhere)
• Assess for other causes of falls (orthostatic hypotension, medications, gait disorders)
• Provide careful observation rather than antimicrobial treatment
• Only treat if patient develops local genitourinary symptoms (dysuria, frequency, urgency, suprapubic pain) or systemic signs (fever, hemodynamic instability) 1

This recommendation prioritizes avoiding the substantial harms of unnecessary antibiotics in a vulnerable population where bacteriuria is extremely common but rarely the cause of acute symptoms. 1

Why Not Treating Matters: The Harms of Unnecessary Treatment

Treating asymptomatic bacteriuria when not indicated causes: 1, 2, 4

• Increased antimicrobial resistance (both in the individual and community)
• Clostridioides difficile infection risk
• Drug adverse effects (allergic reactions, organ toxicity)
• Selection for more resistant reinfecting organisms
• Increased healthcare costs
• No reduction in symptomatic UTI, surgical site infections, or mortality 6, 7

Common Pitfalls to Avoid

1. Do not treat based on colony count alone without symptoms 4
2. Do not treat based on pyuria alone 1, 4
3. Do not confuse orthopedic surgery with urologic surgery—prosthetic joint infections are caused by skin flora (staphylococci), not urinary pathogens, so treating asymptomatic bacteriuria before total knee replacement provides zero benefit 2
4. Do not extend antibiotic courses beyond 1-2 doses for urologic procedures—prolonged courses increase harm without additional benefit 1
5. Do not screen populations where you should not treat—finding bacteriuria creates pressure to treat unnecessarily 4, 7

Diagnostic Criteria (When Screening Is Indicated)

For women: Two consecutive voided urine specimens with the same organism at ≥10^5 CFU/mL 1, 4

For men: Single clean-catch specimen with ≥10^5 CFU/mL 1, 4

For catheterized patients (either sex): Single specimen with ≥10^2 CFU/mL 1