Risk factors and outcomes of bloodstream infections caused by Acinetobacter baumannii: a case-control study.

The risk factors and outcomes of patients with bloodstream infections (BSIs) caused by Acinetobacter baumannii are major concerns in clinical therapy. Multicenter case-control studies were performed to compare the clinical characteristics of 47 A. baumannii BSI patients and 124 matched controls with nonbloodstream A. baumannii infections and the clinical and molecular characteristics of BSI survivors and nonsurvivors. Additionally, the mortality of BSIs was assessed. The clinical characteristics, including neutropenia, ICU admission prior to positive culture, primary infection in the central nervous system, and carbapenem use prior to positive culture, were independently associated with BSI caused by A. baumannii. The mortality of the BSI patients was significantly higher than that of the controls. A high Pitt bacteremia score was found to be an independent predictor of mortality in the BSI patients. The healthcare-associated factors, disease severity level, or antibiotic usage increased the risks of A. baumannii BSI and related mortality.