Outcomes of Acinetobacter baumannii infection in critically ill burned patients

The objective of this study was to determine the incidence of drug resistance among isolates of Acinetobacter baumannii from our Burn Intensive Care Unit (BICU), the rate of clinical cure, and the mortality rate. We undertook a retrospective review of all cases of infection from the BICU between January 2004 and November 2005. The group consisted of 24 men (80%) and 6 women with a mean age of 43 years (range, 17-76 years, +/-14.5 years). Mean TBSA burned was 43% (range, 9-75%, +/-19%). Mean BICU length of stay was 49 days (range, 5-118 days, +/-30 days). Patients developed their first infection after a mean of 16 days (5-73 days, +/-14 days). The initial site of infection was bronchoalveolar lavage in 21 (70%), blood in 6 (20%), central venous catheter tip in 2 (7%), and urine in 1 (3%). The isolates displayed resistance to imipenem in 87% of cases. No organism displayed resistance to colistin (polymixin E). Patients were treated with colistin in 20 cases (67%), with amikacin in 8 cases (27%), and with imipenem in 2 cases (7%). A total of 10 patients (33%) died, 1 from gastrointestinal bleeding and 9 from active infection, giving an infection related mortality of 30%. In 21 cases (70%), a cure was achieved with a mean duration of treatment of 16 days (range, 4-30 days, +/-7 days). The majority of A. baumannii isolates were multidrug resistant; however, no isolate displayed resistance to colistin. Cure rate was 70% and infection-related mortality reached 30%. More investigation is warranted to improve prevention and to assess new therapeutic agents.