Treatment of UTI in Patients with Indwelling Catheters
For symptomatic catheter-associated UTI, replace the catheter if it has been in place ≥2 weeks before starting antibiotics, obtain urine culture from the new catheter, initiate empirical broad-spectrum therapy covering Enterobacteriaceae and Enterococci, and treat for 7 days if symptoms resolve promptly or 10-14 days if response is delayed. 1, 2, 3
Critical First Step: Catheter Replacement
Replace the indwelling catheter before initiating antimicrobial therapy if it has been in place for ≥2 weeks at the onset of symptomatic UTI. 2, 4, 3 This single intervention:
- Decreases polymicrobial bacteriuria 2, 3
- Shortens time to clinical improvement 2, 3
- Lowers rates of UTI recurrence within 28 days after therapy 2, 3
The rationale is that biofilms develop on both internal and external catheter surfaces, protecting uropathogens from antimicrobials and the host immune response, making bacteria inherently resistant to treatment through an old catheter. 4, 5
After replacing the catheter, obtain a urine culture specimen by allowing urine to accumulate while plugging the new catheter before starting antibiotics. 2, 3
Empirical Antibiotic Selection
For patients with systemic symptoms (fever, hemodynamic instability, flank pain, altered mental status), initiate empirical broad-spectrum therapy immediately: 1, 3
Use combination therapy with one of the following: 1, 3
- Amoxicillin plus an aminoglycoside
- Second-generation cephalosporin plus an aminoglycoside
- Intravenous third-generation cephalosporin
Ciprofloxacin should only be used if: 1, 3
- Local resistance rate is <10%
- Patient does not require hospitalization
- Entire treatment can be given orally
- Patient has anaphylaxis to β-lactam antimicrobials
Do not use fluoroquinolones empirically if: 1
- Patient is from a urology department
- Patient has used fluoroquinolones in the last 6 months
The microbial spectrum in catheter-associated UTI is broader than uncomplicated UTI, with E. coli, Proteus spp., Klebsiella spp., Pseudomonas spp., Serratia spp., and Enterococcus spp. being most common, and antimicrobial resistance is more likely. 1
Treatment Duration Algorithm
For patients with prompt symptom resolution (hemodynamically stable and afebrile for ≥48 hours): treat for 7 days. 1, 2, 3
For patients with delayed response to treatment: extend therapy to 10-14 days. 1, 2, 3
For men when prostatitis cannot be excluded: treat for 14 days. 1, 3
In critically ill patients with adequate source control, short-course antibiotic therapy (3-5 days) with early re-evaluation according to clinical course and laboratory parameters is recommended. 1
Tailoring Therapy
Once culture and susceptibility results are available, de-escalate to targeted antimicrobial therapy. 1 Adjust the dose and timing of antimicrobial administration based on: 1
- Patient's weight
- Renal clearance
- Liver function
Post-Treatment Catheter Management
Remove the indwelling catheter as soon as clinically appropriate after completing antibiotic treatment to reduce risk of recurrent infection. 2, 3 Do not remove the catheter before completing the full antibiotic course, as this leads to persistent infection. 3
For patients with recurrent UTIs and an indwelling catheter, consider urodynamic evaluation to identify risk factors such as elevated post-void residual or vesicoureteral reflux. 2
Critical Pitfalls to Avoid
Do NOT treat asymptomatic bacteriuria in catheterized patients. 1, 2, 4, 3 The Infectious Diseases Society of America strongly recommends against screening for or treating asymptomatic bacteriuria in patients with short-term (<30 days) or long-term indwelling catheters, as this does not reduce subsequent catheter-associated UTI and increases antimicrobial resistance. 1, 2, 4
Do NOT use daily antibiotic prophylaxis in patients with long-term indwelling catheters. 2, 4 This does not prevent UTI and increases bacterial resistance. 2
Do NOT administer prophylactic antimicrobials routinely at catheter placement, removal, or replacement. 4, 3 This promotes antimicrobial resistance without reducing catheter-associated UTI. 4, 3
Do NOT fail to replace catheters in place ≥2 weeks before treatment. 2, 4, 3 This reduces treatment efficacy due to biofilm formation. 4, 3
Do NOT start antibiotics before obtaining cultures. 2, 3 This may lead to inappropriate antibiotic selection given the high likelihood of resistant organisms in catheter-associated UTI. 3