Treatment of Catheter-Related UTI Sensitive to Levofloxacin
For a catheter-associated UTI with confirmed levofloxacin susceptibility, treat with levofloxacin 750 mg once daily for 5 days if the patient is not severely ill, or 7 days for standard cases with prompt symptom resolution. 1
Pre-Treatment Management
Obtain a urine culture before initiating antimicrobial therapy due to the wide spectrum of potential infecting organisms and increased likelihood of antimicrobial resistance in catheter-associated UTIs. 1
Replace the catheter if it has been in place for ≥2 weeks at the onset of infection and is still indicated, as this hastens symptom resolution and reduces risk of subsequent bacteriuria and recurrent infection. 1 The catheter biofilm may harbor organisms not accurately reflected in urine cultures, so obtain culture specimens from the freshly placed catheter prior to initiating therapy if feasible. 1
Remove the catheter entirely as soon as clinically appropriate, as duration of catheterization is the most important risk factor for CAUTI development. 2
Levofloxacin Dosing and Duration
For Non-Severely Ill Patients
- Levofloxacin 750 mg once daily for 5 days is appropriate for patients with catheter-associated UTI who are not severely ill. 1
- This high-dose, short-course regimen achieved 79% microbiologic eradication in catheterized patients compared to 53% with ciprofloxacin 10-day therapy in a multicenter randomized trial. 1
- The 750 mg dose maximizes concentration-dependent bactericidal activity and maintains urinary concentrations 50-fold higher than the MIC90 of most sensitive uropathogens throughout the dosing interval. 3
For Standard Cases
- 7 days of treatment is recommended for patients with prompt resolution of symptoms (defervescence by 72 hours), regardless of whether the catheter remains in place. 1
For Delayed Response
- Extend treatment to 10-14 days for patients with delayed clinical response (persistent fever beyond 72 hours). 1
- Consider urologic evaluation if symptoms do not resolve promptly. 1
Special Population: Young Women Post-Catheter Removal
- A 3-day antimicrobial regimen may be considered for women ≤65 years who develop catheter-associated UTI without upper urinary tract symptoms after the indwelling catheter has been removed. 1
Pharmacokinetic Rationale
Levofloxacin achieves excellent urinary concentrations with the 750 mg dose, maintaining levels of 329.1 mg/L at 0-2 hours post-dose and 168.1 mg/L at 8-12 hours, ensuring urinary AUC/MIC ratios >125 hours for optimal bactericidal activity against catheter-related uropathogens. 3
The oral formulation is rapidly absorbed and bioequivalent to intravenous administration, allowing seamless transition between routes based on clinical status. 4, 5
Important Caveats
Data are insufficient to make the 5-day recommendation for other fluoroquinolones besides levofloxacin. 1 Ciprofloxacin requires 10 days of therapy and showed inferior microbiologic eradication rates (53% vs 79%) in catheterized patients. 1
Avoid moxifloxacin for UTI treatment due to uncertainty regarding effective urinary concentrations. 1
Local antimicrobial resistance patterns should guide empirical therapy choices, though levofloxacin susceptibility has remained stable at 98-99% for uropathogens. 2, 6
Adjust regimens based on culture and susceptibility results and clinical course, as catheter-associated UTIs have a broader microbial spectrum including E. coli, Proteus, Klebsiella, Pseudomonas, Serratia, and Enterococcus species with higher resistance rates than uncomplicated UTIs. 2