Comparison of colistin and colistin/sulbactam for the treatment of multidrug resistant Acinetobacter baumannii ventilator-associated pneumonia

To compare clinical and microbiological efficacy of colistin and colistin/sulbactam for the treatment of multidrug-resistant (MDR) Acinetobacter baumannii VAP in intensive care units (ICUs). In this retrospective analysis, patients (> 16 years-old) who received IV colistin or colistin/sulbactam for the treatment of MDR A. baumannii VAP were evaluated. The clinical and microbiological responses to therapies were assessed on the fifth day and at the end of the therapy. During the study period, 89 patients were enrolled into the study. Fifty-two (58.4 %) patients received colistin and 37 (41.6 %) patients received colistin/sulbactam therapy. The median APACHE II score was higher and diabetes mellitus was more common in the colistin/sulbactam group (p < 0.05). However, other demographic characteristics were not statistically significant between groups. On the fifth day of colistin and colistin/sulbactam therapies, clinical response rates were 40.4 and 43.2 %, respectively. At the end of the therapies, clinical response rates were 29.8 and 40 %, respectively. The bacteriological response rates were 72.3 and 85.7 % in colistin and colistin/sulbactam groups, respectively. There were no statistically significant differences in clinical cure rates or bacteriological clearance rates between the two groups. The colistin/sulbactam combination therapy is promising in severe MDR A. baumannii VAP. Although, the difference was not statistically significant, clinical cure rates or bacteriological clearance rates were better in the combination group than colistin monotherapy.