Clinical predictors of the leading pathogens in human immunodeficiency virus-infected adults with community-onset bacteremia in the emergency department: The importance of transmission routes

Background/Purpose: To investigate the clinical characteristics and pathogens of community-onset bacteremia among human immunodeficiency virus (HIV)-infected adults as well as to establish the clinical predictors of the major microorganisms. Methods: An observational cohort study was conducted retrospectively between January 2007 and December 2012. Demographic characteristics and pathogens determined from chart records were analyzed. Results: Of the 121 eligible HIV adults with bacteremia, there was a male predominance (106 patients, 87.6%); elderly individuals (age ≥ 65 years) accounted for only 2.5% of the study population (3 patients). Of the total microorganisms isolated (n = 123), Staphylococcus aureus (55, 44.7%) and Salmonella enterica (17, 13.8%) were the common pathogens. In a multivariate analysis, the leading two significant predictors of S. aureus infection were infective endocarditis (odds ratio, 11.49; p = 0.001) and transmission risk with injection drug users (IDUs; odds ratio, 6.22; p = 0.001). In addition, transmission risk with men who have sex with men (MSM; odds ratio, 37.49; p = 0.001) was the leading clinical predictor of S. enterica infection. In further analyses, a strong linear-by-linear correlation between S. aureus infection and IDU (γ = 0.94, p = 0.02) as well as between S. enterica infection and MSM (γ = 0.96, p = 0.01) was evidenced. Conclusion: Focusing on the two key pathogens in HIV-infected adults with community-onset bacteremia, IDU was one of independent predictors associated with S. aureus infection, whereas MSM was the leading risk factor of S. enterica infection. Although the proposed predictive model of these pathogens has been not established, a scoring system involving the transmission risk of HIV may be of use for the early identification of these patients for clinicians.