What is the recommended treatment for a Klebsiella urinary tract infection (UTI)?

Treatment of Klebsiella Urinary Tract Infections

For Klebsiella UTIs, treatment should be guided by antimicrobial susceptibility testing, with carbapenems recommended for severe infections and complicated UTIs caused by resistant strains, while aminoglycosides, fluoroquinolones, or nitrofurantoin may be appropriate for uncomplicated cases depending on susceptibility patterns.

Classification and Initial Approach

• Klebsiella UTIs should be classified as either uncomplicated or complicated, as this determines treatment approach 1
• Complicated UTIs occur when patients have underlying factors such as urological abnormalities, immunosuppression, diabetes, pregnancy, or healthcare-associated infections 1
• Klebsiella pneumoniae is one of the common uropathogens in complicated UTIs, with higher likelihood of antimicrobial resistance compared to uncomplicated infections 1
• Urine culture and susceptibility testing should always be performed before initiating treatment for suspected Klebsiella UTI 1

Treatment for Uncomplicated Klebsiella UTI

• For uncomplicated cystitis due to susceptible Klebsiella strains:

  • Nitrofurantoin is recommended as a first-line option if the organism is susceptible 1, 2
  • Trimethoprim-sulfamethoxazole can be used if local resistance rates are <20% 1, 3
  • Fluoroquinolones (ciprofloxacin, levofloxacin) should be avoided as empiric therapy if local resistance rates are >10% or if the patient has used fluoroquinolones in the last 6 months 1
  • Oral cephalosporins such as cefpodoxime or ceftibuten are second-line options 1, 3

• For uncomplicated pyelonephritis:

  • Initial parenteral therapy with ceftriaxone (1-2g daily) followed by oral therapy based on susceptibility 1
  • Ciprofloxacin (500-750mg twice daily for 7 days) or levofloxacin (750mg daily for 5 days) if susceptible 1
  • Treatment duration should be 7-14 days depending on clinical response 1

Treatment for Complicated Klebsiella UTI

• For complicated UTIs with systemic symptoms, recommended empiric therapy includes 1:

  • Amoxicillin plus an aminoglycoside
  • A second-generation cephalosporin plus an aminoglycoside
  • An intravenous third-generation cephalosporin

• For carbapenem-resistant Klebsiella (CRE) causing UTIs 1:

  • Ceftazidime-avibactam 2.5g IV q8h (weak recommendation, very low quality evidence)
  • Meropenem-vaborbactam 4g IV q8h or imipenem-cilastatin-relebactam 1.25g IV q6h (weak recommendation, low quality evidence)
  • Plazomicin 15mg/kg IV q12h (weak recommendation, very low quality evidence)
  • Single-dose aminoglycoside for simple cystitis due to CRE (weak recommendation, very low quality evidence)

• For ESBL-producing Klebsiella UTIs 1, 4:

  • Carbapenems are recommended for severe infections (strong recommendation, moderate certainty of evidence)
  • For non-severe infections without septic shock, consider:
    • Aminoglycosides for short durations of therapy (conditional recommendation, moderate certainty of evidence)
    • Intravenous fosfomycin (strong recommendation, high certainty of evidence)
    • High-dose amoxicillin with clavulanic acid may be an alternative in select cases (2.875g amoxicillin with 125mg clavulanic acid twice daily)

Treatment Duration

• For uncomplicated cystitis: 3-5 days of therapy 1
• For uncomplicated pyelonephritis: 7 days of therapy 1
• For complicated UTIs: 7-14 days (14 days for men when prostatitis cannot be excluded) 1
• When the patient is hemodynamically stable and has been afebrile for at least 48 hours, a shorter treatment duration (e.g., 7 days) may be considered 1

Special Considerations

• Aminoglycosides (gentamicin, amikacin) have shown good efficacy against Klebsiella species, including some resistant strains 1, 5, 6
• Aminoglycosides achieve high urinary concentrations and can be effective even as single-dose therapy for cystitis 1
• Tigecycline should be avoided for UTIs as it has been associated with treatment failure 6
• Strain type may impact clinical outcomes, with ST258A strains of carbapenem-resistant K. pneumoniae associated with higher failure rates 6
• For pediatric patients with complicated UTIs due to Klebsiella, ciprofloxacin is not a drug of first choice due to increased incidence of adverse events related to joints and surrounding tissues 7

Monitoring and Follow-up

• Clinical response should be assessed within 48-72 hours of initiating therapy 1
• If no improvement is seen, reassess diagnosis and consider alternative antimicrobial therapy based on culture results 1
• For recurrent Klebsiella UTIs, evaluate for underlying urological abnormalities or complicating factors 1
• Antimicrobial stewardship principles should be followed, including de-escalation to narrower-spectrum antibiotics when possible based on susceptibility results 1