Abstract:Objective To assess the risk factors for carbapenem-resistant Acinetobacter baumannii (CRAB) bloodstream infection (BSI) and 28-day short-term mortality in elderly patients, and provide reference for the prevention and treatment of CRAB BSI. Methods Clinical data of patients aged ≥ 60 years and diagnosed with AB BSI in a hospital in Yulin City from January 2013 to December 2022 were retrospectively analyzed, including demogra-phic and microbiological characteristics, as well as clinical outcomes of the patients. Variables which were significant in univariate analysis were selected for multivariate analysis using binary logistic regression model and Cox proportional hazards model. Independent risk factors for infection were further determined, and survival analysis was performed using Kaplan-Meier curve. Results A total of 150 patients were included in the study, out of which 16 patients (10.7%) had CRAB BSI and 134 had carbapenem-sensitive AB (CSAB) BSI. The 28-day short-term mortality of AB BSI in elderly patients was 15.3% (23/150, 95%CI: 9.6%-21.1%), and the short-term mortality of CRAB BSI was higher than that of CSAB ([56.3%, 9/16] vs[10.4%, 14/134]). Deep venous catheterization (OR: 15.598, 95%CI: 1.831-132.910) and combined infections of other sites (OR: 15.449, 95%CI: 1.497-159.489) were related to CRAB BSI in elderly patients. The independent risk factors for 28-day mortality in elderly patients with AB BSI were hemodialysis (OR: 11.856, 95%CI: 2.924-48.076), intensive care unit admission (OR: 9.387, 95%CI: 1.941-45.385), and pulmonary infection being suspected source of bacteremia (OR: 7.019, 95%CI: 1.345-36.635). Conclusion The occurrence of CRAB BSI in elderly patients is related to the combined infection of other sites and deep vein catheterization. Hemodialysis, admission to ICU, and pulmonary infection being suspected source of bacteremia are independent risk factors for the prognosis of AB BSI in elderly patients.