What antibiotics are recommended for treating catheter-associated urinary tract infections (UTIs)?

Antibiotic Treatment for Catheter-Associated UTIs

For catheter-associated urinary tract infections (CA-UTIs), empirical treatment should include antibiotics active against both gram-positive and gram-negative organisms, with catheter removal or replacement before starting therapy whenever possible. 1, 2

Initial Management

• Replace or remove the indwelling catheter before starting antimicrobial therapy to improve clinical outcomes and reduce subsequent infection risk 1, 2
• If the catheter has been in place for ≥2 weeks, replacement is particularly important as it decreases polymicrobial bacteriuria, shortens time to clinical improvement, and lowers rates of CA-UTI recurrence 3
• Obtain urine culture before initiating antimicrobial therapy to guide targeted treatment 1

Empirical Antibiotic Selection

First-line empirical therapy:

• Vancomycin plus gram-negative coverage based on local antibiogram data 1
  • Vancomycin: 20 mg/kg loading dose, then 500 mg during the last 30 minutes of each subsequent dialysis session (for hemodialysis patients) 1
  • Alternative to vancomycin: Cefazolin (in settings with low prevalence of methicillin-resistant staphylococci) 1

Gram-negative coverage options:

• Third- or fourth-generation cephalosporins (e.g., ceftazidime, cefepime) 1
• Aminoglycosides (e.g., gentamicin) - use with caution due to nephrotoxicity risk 1
• Avoid fluoroquinolones empirically in patients who have used them in the previous 6 months due to increased resistance risk 1, 4

For suspected fungal infection:

• Echinocandins (caspofungin, micafungin, anidulafungin) 1
• Fluconazole (200 mg daily) 1
• Amphotericin B for severe infections 1

Duration of Treatment

• 7 days for patients with prompt clinical response 4
• 10-14 days for patients with:
  • Delayed clinical response
  • Male patients where prostatitis cannot be excluded
  • Complicated infections or underlying urological abnormalities 4

Special Considerations

• For patients with severe sepsis, collaborative treatment involving urologists, intensive care, and infectious disease specialists is recommended 1
• Establish source control by alleviating any obstruction and draining significant abscesses within the urinary tract 1
• For patients with history of previous antibiotic therapy or healthcare-associated bacteremia, empirical treatment should cover multiresistant uropathogens 5

Antibiotic Lock Therapy for Catheterized Hemodialysis Patients

For hemodialysis patients with catheter-related infections, antibiotic lock therapy may be considered with:

• Vancomycin (2.5-5.0 mg/mL) for gram-positive coverage 1
• Ceftazidime (0.5 mg/mL) or gentamicin (1.0 mg/mL) for gram-negative coverage 1

Common Pitfalls to Avoid

• Do not treat catheter-associated asymptomatic bacteriuria in general 1, 3
• Do not use prophylactic antimicrobials to prevent CA-UTI 1, 3
• Do not apply topical antiseptics or antimicrobials to the catheter, urethra, or meatus 1
• Avoid removing the catheter before completing appropriate antibiotic treatment, which may lead to persistent infection 2
• Avoid failing to obtain cultures before initiating antibiotics, which may lead to inappropriate antibiotic selection 2, 3

Emerging Treatment Options for Resistant Organisms

For multidrug-resistant organisms, newer options include:

• Ceftazidime-avibactam, ceftolozane-tazobactam for ESBL-producing organisms 6, 7
• Meropenem-vaborbactam, imipenem-cilastatin-relebactam for carbapenem-resistant organisms 6, 7
• Cefiderocol for multidrug-resistant gram-negative infections 6, 7