What is the recommended treatment for a urinary tract infection (UTI) caused by Pseudomonas aeruginosa bacteria?

Treatment of Pseudomonas aeruginosa Urinary Tract Infections

For urinary tract infections caused by Pseudomonas aeruginosa, the recommended treatment is an antipseudomonal β-lactam such as piperacillin-tazobactam, ceftazidime, cefepime, or a carbapenem (meropenem), with consideration for combination therapy in complicated cases.

First-line Treatment Options

Uncomplicated Pseudomonas UTI:

• Ciprofloxacin 500mg orally twice daily (if local resistance rates <10%) 1
• Levofloxacin 750mg orally daily (if local resistance rates <10%) 1

Complicated Pseudomonas UTI with systemic symptoms:

• Intravenous therapy options (in order of preference):

  1. Antipseudomonal β-lactam:

     • Piperacillin-tazobactam 3.375-4.5g IV every 6 hours 2
     • Ceftazidime 2g IV every 8 hours 2
     • Cefepime 2g IV every 8-12 hours 2
     • Meropenem 1g IV every 8 hours 3

  2. For severe infections or suspected resistance, consider combination therapy:

     • Antipseudomonal β-lactam + aminoglycoside (e.g., tobramycin 5-7mg/kg/day) 2, 4
     • Antipseudomonal β-lactam + fluoroquinolone (if susceptible) 1

Treatment Duration

• 7 days for uncomplicated UTI 2
• 10-14 days for complicated UTI 2, 1
• 14 days for men when prostatitis cannot be excluded 2

Special Considerations

Carbapenem-Resistant Pseudomonas aeruginosa (CRPA)

For CRPA infections, options include:

• Colistin 5 mg CBA/kg IV loading dose, then 2.5 mg CBA IV q12h 2
• Ceftolozane-tazobactam 1.5-3g IV q8h (if susceptible) 2
• Ceftazidime-avibactam 2.5g IV q8h (if susceptible) 2

Catheter-Associated UTI

• Remove or replace the urinary catheter if possible 2
• Patients with indwelling catheters have higher rates of febrile UTI (66.7% vs 40.5% in non-catheterized patients) 5
• Short-course systemic antibiotic therapy can postpone biofilm infections for up to 1-2 weeks, but prophylaxis is not recommended due to risk of resistance 2

Monitoring and Follow-up

• Clinical response should be evident within 48-72 hours of appropriate therapy 1
• If no improvement after 72 hours, consider repeat cultures and antibiotic adjustment 1
• Monitor renal function when using aminoglycosides or polymyxins 4

Important Caveats

1. Local resistance patterns should guide empiric therapy choices, as P. aeruginosa resistance rates are increasing globally 1, 6
2. Avoid fluoroquinolones for empirical treatment if:
   • Local resistance rate is >10%
   • Patient has used fluoroquinolones in the last 6 months
   • Patient is from a urology department 2
3. Biofilm formation in catheterized patients may reduce treatment efficacy and increase recurrence rates 2, 7
4. Multidrug resistance is increasingly common in P. aeruginosa, with some strains resistant to virtually all antipseudomonal agents 6

Remember that P. aeruginosa UTIs are typically considered complicated infections, and appropriate management of any underlying urological abnormality is mandatory for successful treatment 2.