How should a catheter-associated urinary tract infection be managed in an elderly man with a permanent urinary catheter?

Management of Catheter-Associated UTI in an Elderly Man with Permanent Urinary Catheter

Critical First Step: Replace the Catheter Before Starting Antibiotics

If the indwelling catheter has been in place for ≥2 weeks, you must replace it before initiating antimicrobial therapy. 1, 2 This single intervention significantly decreases polymicrobial bacteriuria (p = 0.02), shortens time to clinical improvement at 72 hours (p < 0.001), and lowers CA-UTI recurrence within 28 days (p = 0.015). 1, 2

• Obtain the urine culture specimen from the newly placed catheter before starting antibiotics, not from the old catheter. 1, 2
• The biofilm that forms on catheters in place ≥2 weeks protects bacteria from antimicrobials and makes treatment through an old catheter inherently less effective. 3, 4
• Do not delay catheter replacement—this is crucial for treatment success and should be done before antibiotics. 1

Confirm Symptomatic Infection Before Treating

Only treat if the patient has symptoms of CA-UTI: fever, rigors, altered mental status, flank pain, costovertebral angle tenderness, acute hematuria, pelvic discomfort, or suprapubic pain. 1

• Do not treat asymptomatic bacteriuria in catheterized patients (except in pregnant women or before urologic procedures with anticipated mucosal bleeding), as this promotes antimicrobial resistance without clinical benefit. 1, 2, 3
• Asymptomatic bacteriuria occurs in virtually all patients with long-term catheters and does not require treatment. 4

Empirical Antibiotic Selection

For Moderate-to-Severe CA-UTI or Systemic Symptoms (Fever, Sepsis):

Start with intravenous third-generation cephalosporin: ceftriaxone 1-2 g daily or cefepime 1-2 g twice daily. 1

• Alternative regimens include amoxicillin plus an aminoglycoside, or a second-generation cephalosporin plus an aminoglycoside. 1, 2
• Consider broader coverage for multidrug-resistant organisms if the patient has recent hospitalization, long-term care facility residence, or known colonization with resistant organisms. 1

For Mild-to-Moderate CA-UTI Without Systemic Signs:

Levofloxacin 750 mg orally once daily is the preferred oral agent, achieving superior microbiologic eradication rates (79% vs 53% for ciprofloxacin, 95% CI 3.6%-47.7%). 1

• Avoid fluoroquinolones if the patient has used them in the last 6 months or if local resistance exceeds 10%. 1, 2
• Avoid moxifloxacin because urinary concentrations sufficient for treatment are uncertain. 1
• Adjust fluoroquinolone doses when creatinine clearance is <50 mL/min. 1

Treatment Duration

Standard duration is 7 days for patients who become hemodynamically stable and afebrile for ≥48 hours with prompt symptom resolution. 1, 2

• Extend to 10-14 days for patients with delayed response or persistent fever beyond 72 hours. 5, 1, 2
• For men, consider 14 days of treatment when prostatitis cannot be excluded. 2
• A shortened 5-day course of levofloxacin 750 mg may be considered in non-severely ill patients when susceptibility is confirmed. 1

Adjust Therapy Based on Culture Results

• Narrow antimicrobial therapy once culture and susceptibility results are available. 5
• CA-UTI is frequently polymicrobial and often caused by multidrug-resistant organisms, making culture-directed therapy essential. 1

When to Escalate or Investigate Further

If fever persists >72 hours despite appropriate therapy for a susceptible organism, promptly evaluate for:

• Alternative infection sources: bloodstream infection, abscess, or prostatitis in men. 1
• Obtain blood cultures if not already done, as catheterized patients have increased risk of bacteremia. 1
• Consider imaging (renal ultrasound or CT) to rule out complicated infection requiring urologic evaluation. 5, 1

Common Pitfalls to Avoid

• Never administer prophylactic antibiotics at catheter placement, removal, or replacement—this promotes resistance without reducing CA-UTI. 1, 2, 3
• Do not remove the catheter before completing antibiotic treatment if it must remain in place for medical reasons. 2
• Do not treat asymptomatic bacteriuria routinely, as antimicrobial treatment does not decrease symptomatic episodes but leads to emergence of more resistant organisms. 3, 4
• Do not delay catheter replacement when the device has been in place ≥2 weeks, as biofilm formation markedly diminishes treatment efficacy. 1, 3

Long-Term Prevention Strategies

The single most effective intervention is catheter removal when no longer medically necessary, as duration of catheterization is the principal determinant of infection and complications. 6, 4

• Avoid unnecessary catheterizations and remove catheters as soon as possible. 7, 6
• Maintain a closed drainage system and adhere to appropriate catheter care techniques. 4
• Hand hygiene adherence is a critical general prevention measure. 6