Impact of the initiation time of colistin treatment for Acinetobacter infections

This study aimed to address the relationship between the timing of colistin therapy and the outcome, defined as all-cause mortality in the intensive care unit (ICU). A retrospective study was undertaken in a 16-bed ICU of a 750-bed tertiary care hospital. A total of 46 patients who had been administered intravenous colistin treatment for colistin-susceptible-only Acinetobacter infections were included in the study. Colistin treatment was initiated in 26 (56.5 %) patients within 24 h of the diagnosis (early administration of colistin), whereas the rest of the patients had obtained delayed treatment (delayed administration of colistin). Of the 46 patients, 21 (45.6 %) died. With univariate analysis, age, age greater than 65 years, APACHE II score more than 20 at baseline, and delayed administration of colistin were found to be significant (p 0.05). Logistic regression analysis revealed a significant association between delayed administration of colistin [adjusted odds ratio (OR), 5.06; confidence interval (CI), 1.18-21.67], and adverse outcome. Other variables included in the final model were underlying disease (OR, 2.81; CI, 1.15-6.84) and APACHE II score at baseline20 (OR, 3.81; CI, 0.77-18.75). This study found that delayed administration of colistin and underlying disease were independently associated with adverse outcome.