What is the recommended treatment for asymptomatic Urinary Tract Infections (UTIs)?

Treatment of Asymptomatic Bacteriuria (UTI)

Asymptomatic bacteriuria should NOT be treated in the vast majority of patients—treatment is only indicated in pregnant women and patients undergoing urological procedures that breach the mucosa. 1

Definition

Asymptomatic bacteriuria is bacterial growth >10^5 CFU/mL in two consecutive urine samples in women (or a single sample in men) without any urinary tract symptoms, representing commensal colonization rather than true infection. 1

When to Treat: Only Two Indications

1. Pregnant Women

• Screen and treat asymptomatic bacteriuria in all pregnant women, preferably in the first trimester. 1
• This reduces the risk of pyelonephritis during pregnancy (untreated ASB carries approximately 40% risk of developing pyelonephritis). 2
• Treatment options include:
  • Standard short-course therapy (4-7 days) with nitrofurantoin, fosfomycin trometamol, or third-generation cephalosporins 1, 3
  • Single-dose fosfomycin trometamol 3g 1
  • β-lactams, nitrofurantoin, or fosfomycin are preferred agents 4
• Screen with a single urine culture in the first trimester only. 4

2. Before Urological Procedures That Breach Mucosa

• Administer single-dose antimicrobial prophylaxis prior to procedures including: 2
  • Ureteroscopic stone removal
  • Percutaneous nephrolithotomy
  • Transurethral resection procedures
  • Any procedure where the mucosal barrier will be broken
• Base antibiotic selection on prior urine culture results and/or local antibiogram. 2

When NOT to Treat: Do Not Screen or Treat in These Populations

The following groups should NOT be screened or treated for asymptomatic bacteriuria, as treatment has not been shown to improve clinical outcomes and may cause harm: 1

• Non-pregnant women without risk factors
• Patients with well-regulated diabetes mellitus
• Postmenopausal women
• Elderly institutionalized patients
• Patients with dysfunctional and/or reconstructed lower urinary tract
• Renal transplant patients (>1 month post-transplant)
• Non-renal solid organ transplant patients
• Patients before arthroplasty surgery
• Patients with recurrent UTIs
• Older patients with functional/cognitive impairment who experience delirium or falls
• Patients before cardiovascular surgeries

Harms of Unnecessary Treatment

Treating asymptomatic bacteriuria in populations without clear benefit causes significant harm: 1

• Increased antimicrobial resistance
• Risk of Clostridioides difficile infection
• Adverse drug effects
• Eradication of potentially protective bacterial strains
• Higher healthcare costs

Critical Clinical Pitfalls

• Never perform surveillance urine testing in asymptomatic patients, including those with recurrent UTIs. 1
• Do not confuse asymptomatic bacteriuria with symptomatic UTI—the presence of bacteria alone without symptoms does not warrant treatment in most populations. 1
• Positive urine cultures in catheterized patients, elderly patients, or diabetic patients without symptoms should not trigger antibiotic treatment. 1
• If antibiotics are initiated for suspected symptomatic UTI, always obtain urine culture before starting treatment to guide therapy. 1