Burden of bacterial bloodstream infection—a brief update on epidemiology and significance of multidrug-resistant pathogens

Abstract

BACKGROUND Bloodstream infections comprise a wide variety of pathogens and clinical syndromes with considerable overlap with similar syndromes of non-bacteremic infections and quite diverse risk factors, therapeutic implications and outcomes. Yet, this heterogenous "entity" has the advantage to be pathogen-defined compared with the broad and even more heterogenous entity "sepsis", and thus has become helpful for clinicians and epidemiologists for research and surveillance purposes. The increasing availability of population-based and large multicenter well-defined cohort studies should allow to assess with much confidence and details its burden, the significance of antimicrobial resistance, and areas of uncertainty regarding the further epidemiologic evolution and optimized treatment regimens. AIM To review key aspects of bloodstream infection epidemiology and burden and summarize recent news and questions concerning critical developments. SOURCES Peer-reviewed articles based on the search terms 'bloodstream infection' and 'bacteremia' combined with the terms 'epidemiology' and 'burden'. The emphasis was on new information from studies in adult patients and on the added burden due to pathogen resistance to first- and second-line antimicrobial agents. CONTENT Topics covered include recent developments in the epidemiology of bloodstream infection due to key pathogens and published information about the relevance of resistance for patient outcomes. IMPLICATIONS Despite the availability of population-based and an increasing number of large well-defined multicenter cohort studies, more surveillance and systematic data on BSI epidemiology at regional level and in resource-limited settings may be needed to better design new ways for prevention and define the need for and further develop optimized therapeutic strategies.