Comparative results of preemptive therapies in mechanically ventilated patients with carbapanem-resistant Acinetobacter baumannii (CRAB)

Purpose: Although CRAB have been found in a lot of mechanically ventilated patients, it is difficult to consider CRAB as a true pathogen of pneumonia. In spite of higher renal toxicity, preemptive intravenous (IV) colistin is always considered after culture results of endobronchial aspirates to prevent fatal outcomes of pneumonia. The objective of this study is to compare the clinical results of several preemptive therapies. Methods: Data between Jan. 2012 and Sep. 2013 in mechanically ventilated patients with CRAB in their endotracheal aspirates were analyzed. According to the antimicrobial agents, treatment arms were classified as 4 groups; (1) no treatment, (2) conventional dose of Cefoperazone/sulbactam + minocycline (Cef/sul+Mcln), (3) nebulized colistin, and (4) IV colistin groups. Thirty-day mortality, Acinetobacter-growing days, and acute kidney injury (AKI)-free days were compared among these groups. Results: Data of 173 patients were analyzed. No treatment, Cef/Sul+Mcln, nebulized colistin, and IV colistin group were 71, 45, 30, and 27, respectively. Thirty-day mortality and AKI-free days were not different among these groups. Acinetobacter-growing days were shorter in nebulized colistin group than IV colistin group, but not different with Cef/Sul+Mcln group. The multivariate analysis revealed that 30-day mortality was associated with the APACHE II score, AKI-free day after anti-acinetobacter treatments, Cef/sul+Mcln group compared with IV colistin group. Conclusion: Cef/sul+Mcln and nebulized colistin can be consideered as better preemptive therapies than IV colistin. IV colistin as a preemptive therapy should be carefully considered.