OXA-48 Dominance Meets Ceftazidime-Avibactam: A Battle Against Life-Threatening Carbapenem-Resistant Klebsiella pneumoniae Infections in the Intensive Care Unit

Objective In this study, we aimed to describe the outcomes in ICU patients with bloodstream infection (BSI) or ventilatory-associated pneumonia (VAP) due to carbapenem-resistant Klebsiella pneumoniae (CRKP) who received ceftazidime-avibactam treatment at a tertiary care university hospital. Methods Patients aged 18 years or older who were admitted to the Anesthesiology and Reanimation ICU at Bursa Uludag University Faculty of Medicine Hospital between June 13, 2021, and July 16, 2023, and diagnosed with BSI or VAP due to CRKP were included in this study. Results A total of 42 patients treated with ceftazidime-avibactam were included. Total crude mortality rates were 33.3% on day 14 and 54.8% on day 30. Mortality rates on the 14th and 30th days were 37.5% and 62.5% in patients with BSI and 27.8% and 44.4% in patients with VAP, respectively. There was no statistically significant difference between monotherapy and combination therapy in terms of mortality rates on days 14 and 30, respectively (3/11 vs. 11/31, p=0.620; 5/11 vs. 18/31, p=0.470). Immunosuppression (10/11 vs. 13/31, p=0.005), the Sequential Organ Failure Assessment (SOFA) score ≥8 (at the initiation of treatment; 19/25 vs. 4/17, p<0.001), INCREMENT-CPE score ≥10 (12/16 vs. 3/10, p=0.024) and longer duration (in days) from culture collection to treatment initiation (5.0 ± 0.61 vs. 3.11 ± 0.48, p=0.024) were found to have a statistically significant effect on 30-day mortality. In multivariate analysis, a SOFA score ≥8 at the initiation of treatment (p=0.037, OR: 17.442, 95% CI: 1.187-256.280) was found to be a significant risk factor affecting mortality (30-day). Conclusion The mortality rates of patients with CRKP infection who were followed up in the ICU were found to be high, and it was observed that whether ceftazidime-avibactam treatment was given as a combination or monotherapy did not affect mortality. Further multicentre studies with a larger number of patients are needed to gain a comprehensive understanding of the topic, given that this treatment is typically reserved for documented infections.