Does ciprofloxacin (Cipro) cover Klebsiella species?

From the Guidelines

Ciprofloxacin is a recommended treatment option for infections caused by Klebsiella species, with a typical oral regimen of 500 mg or 750 mg twice daily for 14 days. According to the British Thoracic Society guideline for bronchiectasis in adults 1, ciprofloxacin is listed as a recommended first-line treatment for coliforms, including Klebsiella. The guideline suggests oral ciprofloxacin 500 mg or 750 mg twice daily for 14 days as a treatment option. Some key points to consider when using ciprofloxacin to treat Klebsiella infections include:

• The importance of obtaining cultures and susceptibility testing whenever possible to confirm effectiveness and guide treatment decisions
• The potential for resistance to ciprofloxacin among Klebsiella species, which may require alternative antibiotics such as carbapenems or combination therapy
• The need for patients to complete the full course of antibiotics even if symptoms improve to prevent recurrence and development of resistance. It's also worth noting that ciprofloxacin can be used to treat other types of infections, including those caused by Pseudomonas aeruginosa, with a typical oral regimen of 500 mg twice daily (or 750 mg twice daily in more severe infections) for 14 days 1.

From the FDA Drug Label

Ciprofloxacin has been shown to be active against most strains of the following microorganisms, both in vitro and in clinical infections... Aerobic gram-negative microorganisms ... Klebsiella pneumoniae ... The following in vitro data are available, but their clinical significance is unknown Ciprofloxacin exhibits in vitro minimum inhibitory concentrations (MICs) of 1 μg/mL or less against most (≥ 90%) strains of the following microorganisms; ... Aerobic gram-negative microorganisms ... Klebsiella oxytoca

• Ciprofloxacin covers Klebsiella species: Yes, ciprofloxacin has been shown to be active against most strains of Klebsiella pneumoniae and Klebsiella oxytoca in vitro 2.
• Key points:
  • Ciprofloxacin is active against Klebsiella pneumoniae.
  • Ciprofloxacin is active against Klebsiella oxytoca.
  • The clinical significance of the in vitro data is unknown.

From the Research

Ciprofloxacin Coverage of Klebsiella Species

• Ciprofloxacin is a broad-spectrum fluoroquinolone antibacterial agent that is effective against a wide variety of infections, particularly those caused by Gram-negative pathogens, including Klebsiella species 3.
• However, studies have shown that Klebsiella pneumoniae isolates can be resistant to ciprofloxacin, with resistance rates varying depending on the location and population being studied 4, 5, 6.
• A study published in 2021 found that 7.1% of Klebsiella oxytoca clinical isolates were nonsusceptible to ciprofloxacin 6.
• Another study published in 2021 found that ciprofloxacin resistance was detected in 93% of Klebsiella pneumoniae isolates using a rapid antibiotic susceptibility testing method 5.
• It is essential to note that the effectiveness of ciprofloxacin against Klebsiella species can vary depending on the specific strain and resistance patterns, and therefore, antibiotic susceptibility testing should be performed to guide treatment decisions 4, 5, 6.

Mechanisms of Resistance

• The mechanisms of resistance to ciprofloxacin in Klebsiella species can include mutations in the target enzymes, such as DNA gyrase and topoisomerase IV, as well as the presence of efflux pumps and other resistance genes 7.
• The ISKpn26 element has been shown to mediate mgrB gene disruption, leading to colistin resistance in Klebsiella pneumoniae 4.
• The emergence of carbapenem-resistant and extended-spectrum β-lactamase-producing Klebsiella pneumoniae has renewed interest in developing alternative treatments and vaccines 7.

Clinical Implications

• The increasing resistance of Klebsiella species to ciprofloxacin and other antibiotics highlights the need for rational prescribing practices and the development of new antimicrobial agents 3, 7, 6.
• Clinicians should be aware of the local resistance patterns and use antibiotic susceptibility testing to guide treatment decisions for Klebsiella infections 4, 5, 6.