Aerosolized colistin for the treatment of multidrug-resistant Acinetobacter baumannii pneumonia: experience in a tertiary care hospital in northern Taiwan.

BACKGROUND/PURPOSE Ventilator-associated pneumonia (VAP) due to multidrug-resistant (MDR) Acinetobacter baumannii in critically ill patients presents an emerging challenge to clinicians. Administration of aerosolized colistin as an adjunctive therapy is one therapeutic option mentioned in limited evidence-based studies. This study aimed to evaluate the effectiveness of adjunctive aerosolized colistin treatment for VAP due to MDR pathogens. METHODS We retrospectively reviewed the medical records of patients who had received aerosolized colistin for treatment of VAP due to MDR A. baumannii in our hospital from August to December 2008. RESULTS Forty-five patients were enrolled in our study. The mean age was 71 +/- 15 years. The mean Acute Physiological and Chronic Health Evaluation II (APACHE II) scores on the day of intensive care unit admission and on the first day of aerosolized colistin administration were 22.5 +/- 6.7 and 18.9 +/- 5.7, respectively. The mean duration of intensive care unit stay was 34 +/- 16 days. The mean daily dosage of aerosolized colistin was 4.29 +/- 0.82 million IU, and the mean duration of administration was 10.29 days. Seventeen patients (37.8%) had a favorable microbiological outcome and 26 (57.8%) showed a clinical response. Mortality due to all causes was 42.2%. No adverse effects related to inhaled colistin were recorded. CONCLUSION Aerosolized colistin may be considered as an adjunct to intravenous treatments in patients with VAP due to colistin-susceptible MDR A. baumannii in critically ill patients.