Can vancomycin be discontinued in a patient with a positive blood culture for Klebsiella oxytoca (K. oxytoca) who is being treated with vancomycin and Zosyn (piperacillin-tazobactam)?

From the Guidelines

You can stop vancomycin in this case, as Klebsiella oxytoca is a gram-negative organism that is not covered by vancomycin, which primarily targets gram-positive bacteria. Piperacillin-tazobactam (Zosyn) provides appropriate coverage for Klebsiella species and should be continued as the primary treatment 1. The initial inclusion of vancomycin was likely empiric coverage while awaiting culture results, but now that the pathogen has been identified as Klebsiella, vancomycin no longer adds benefit to the treatment regimen.

However, before discontinuing vancomycin, ensure that there is no concern for polymicrobial infection with gram-positive organisms. Also, review the susceptibility results for the Klebsiella isolate to confirm that it is sensitive to Zosyn. The standard duration of treatment for Klebsiella bacteremia is typically 7-14 days, depending on the source of infection, presence of complications, and clinical response. Remember to obtain follow-up blood cultures to document clearance of the bacteremia. It's worth noting that the provided guidelines, such as the British Thoracic Society guideline for bronchiectasis in adults 1, do not directly address the treatment of Klebsiella oxytoca bacteremia, but the general principles of antimicrobial therapy can be applied.

Some key points to consider when treating Klebsiella infections include:

• The importance of appropriate antimicrobial coverage, such as piperacillin-tazobactam, for gram-negative organisms like Klebsiella
• The need to review susceptibility results to ensure the chosen antibiotic is effective against the specific isolate
• The potential for polymicrobial infections, which may require broader antimicrobial coverage
• The importance of monitoring for complications and adjusting treatment accordingly.

In this case, since the pathogen has been identified and appropriate coverage is being provided by Zosyn, discontinuing vancomycin is a reasonable decision, as it is not necessary for the treatment of Klebsiella oxytoca and may help reduce the risk of adverse effects and promote more judicious use of antimicrobials 1.

From the Research

Antibiotic Treatment for Klebsiella oxytoca Infections

• The patient is currently on vancomycin and zosyn for a positive blood culture of Klebsiella oxytoca, but there is no clear indication that vancomycin is necessary for the treatment of this specific infection 2, 3.
• Klebsiella oxytoca is a Gram-negative bacterium, and vancomycin is typically used to treat Gram-positive bacterial infections 4, 5.
• The provided studies do not specifically address the use of vancomycin in the treatment of Klebsiella oxytoca infections, but they do discuss the increasing resistance of Klebsiella species to various antibiotics, including carbapenems 2, 6.
• Zosyn (piperacillin-tazobactam) is a broad-spectrum antibiotic that may be effective against Klebsiella oxytoca, but the decision to stop vancomycin should be based on the specific circumstances of the patient's infection and the results of antibiotic susceptibility testing 2, 3.

Considerations for Stopping Vancomycin

• Before stopping vancomycin, it is essential to consider the potential risks and benefits, including the possibility of underlying Gram-positive bacterial infections that may require vancomycin treatment 4, 5.
• The decision to stop vancomycin should be made in consultation with an infectious disease specialist or other qualified healthcare professional, taking into account the patient's individual needs and the results of antibiotic susceptibility testing 2, 6, 3.