Effectiveness of ceftazidime/avibactam as a continuous infusion in critically ill patients with OXA-48-producing Klebsiella pneumoniae infection

Introduction. Ceftazidime/avibactam, a novel beta-lactam antibiotic, demonstrates time-dependent bacterial killing; thus, new reports advocate its administration as a continuous infusion, as opposed to bolus or prolonged infusion application. Methods. Critically ill COVID-19 patients (n=10) superinfected with OXA-48-producing Klebsiella pneumoniae susceptible to ceftazidime/avibactam were treated with ceftazidime/avibactam as a continuous infusion for an average of 10 days. The treatment regimen included an initial loading dose, followed by a continuous infusion of ceftazidime/avibactam. These patients were immunocompromised because of severe COVID-19, treatment with corticosteroids, and some solid organ transplant recipients (n=2), all with high disease severity scores. Discussion. Considering the published literature to this date, this is the one of first reports describing the real-life results of using a continuous infusion of ceftazidime/avibactam in the treatment of OXA-48-producing K. pneumoniae superinfection in critically ill COVID-19 patients. Microbiological effectiveness of treatment, evidenced by negativization of microbiological samples, was achieved in eight cases (80%) overall, but in patients with sepsis and urinary tract infection, the cure rate was 100%. Conclusion. The reasons for the low treatment success rates in pneumonia caused by OXA-48-producing K. pneumoniae could be explained by the concurrent severe COVID-19 pneumonia.