Acinetobacter baumannii infection in solid organ transplant recipients.

Introduction: Acinetobacter baumannii can cause serious infection in susceptible patients, but little has been published regarding risk factors for infection and outcomes in solid organ transplant (SOT) recipients.

Methods: We identified A. baumannii infection among adult SOT recipients that occurred between January 2001 and March 31, 2008 at a Chicago transplant center and evaluated characteristics of these infections and outcomes.

Results: Thirty-three individuals developed A. baumannii infection during the study period. Seventy-nine percent had healthcare-associated infection with respiratory tract as the most common site of infection (64%). Eighty-two percent of patients had received antibiotics within two wk prior to A. baumannii infection and multidrug resistance (MDR) or extensive resistance (XDR) occurred in 85%. The median time to onset of infection was five months after transplant. The 30-d mortality was 24% and was associated with XDR. Administration of an appropriate antibiotic within three d was associated with lower 30-d mortality (OR 0.16, p = 0.047). All isolates tested against colistin were susceptible.

Conclusion: SOT recipients with A. baumannii infection had high mortality associated with delay in appropriate antibiotic therapy and XDR organisms. The use of colistin-containing treatment regimens should be considered in these patients when A. baumannii infection is suspected or identified in patients who have received prior antibiotics.