Ceftazidime-Avibactam To Treat Life-Threatening Infections by Carbapenem-Resistant Pathogens in Critically Ill Mechanically Ventilated Patients.

Data on the effectiveness of ceftazidime-avibactam (CAZ-AVI) in critically ill, mechanically ventilated patients are limited. The present retrospective observational cohort study, which was conducted in two general intensive care units (ICUs) in central Greece, compared critically ill, mechanically ventilated patients suffering from carbapenem-resistant Enterobacteriaceae (CRE) infections receiving CAZ-AVI to patients who received appropriate available antibiotic therapy. Clinical and microbiological outcomes and safety issues were evaluated. A secondary analysis in patients with bloodstream infections (BSIs) was conducted. Forty-one patients that received CAZ-AVI (the CAZ-AVI group) were compared to 36 patients that received antibiotics other than CAZ-AVI (the control group). There was a significant improvement in the Sequential Organ Failure Assessment (SOFA) score on days 4 and 10 in the CAZ-AVI group compared to that in the control group (P = 0.006, and P = 0.003, respectively). Microbiological eradication was accomplished in 33/35 (94.3%) patients in the CAZ-AVI group and 21/31 (67.7%) patients in the control group (P = 0.021), and clinical cure was observed in 33/41 (80.5%) versus 19/36 (52.8%) patients (P = 0.010), respectively. The results were similar in the BSI subgroups for both outcomes (P = 0.038 and P = 0.014, respectively). The 28-day survival was 85.4% in the CAZ-AVI group and 61.1% in the control group (log-rank test = 0.035), while there were 2 and 12 relapses in the CAZ-AVI and control groups, respectively (P = 0.042). A CAZ-AVI-containing regime was an independent predictor of survival and clinical cure (odds ratio [OR] = 5.575 and P = 0.012 and OR = 5.125 and P = 0.004, respectively), as was illness severity. No significant side effects were recorded. In conclusion, a CAZ-AVI-containing regime was more effective than other available antibiotic agents for the treatment of CRE infections in the high-risk, mechanically ventilated ICU population evaluated.

Implementation of the Rapid Polymyxin™ NP test directly to positive blood cultures bottles.

The present study assessed the performance of Rapid Polymyxin™ NP test to detect colistin resistance directly from 132 blood cultures found positive for Enterobacterales by FilmArray. Additionally, colistin MICs of isolated microorganisms were determined by the commercial broth microdilution method ComASP™ Colistin, used as the gold standard comparator. The Rapid Polymyxin™ NP test correctly detected all colistin-resistant isolates. However, the test has misidentified as resistant 4 colistin-susceptible isolates (1 Escherichia coli and 3 Klebsiella pneumoniae). Molecular characterization of colistin-resistant isolates showed that K. pneumoniae, which belonged to ST15 and ST147, carried alterations in the mgrB. Moreover, the first Greek mcr-1-positive colistin-resistant E. coli was detected. The rapidity (2-3 h) of the results, combined with its excellent negative predictive value (100%), allows implementation of the test for routine testing of blood cultures mainly in the clinical settings that are endemic for carbapenem-resistant bacteria, avoiding misuse of colistin and preventing the spread of colistin-resistant bacteria.