Optimized detection of bacteria in bloodstream infections

Abstract

Bloodstream infection (BSI) is a life-threatening condition characterized by the presence of pathogens in the blood. It is associated with increased morbidity and mortality, and has to be treated promptly as mortality increases with every hour of delayed treatment. Therefore, rapid and sensitive diagnosis of BSI is essential. The routine diagnostic method for BSI is blood culture, which can only detect culturable pathogens and takes several days to obtain results. The 16S rRNA gene is present in all bacteria and is commonly used as a target for universal bacterial detection in rapid molecular assays such as PCR. However, molecular detection of the 16S gene is hampered by the large amount of human DNA found in blood samples, making diagnostic results aspecific and less sensitive. We have optimized the selection of PCR primers targeting the 16S rRNA gene to avoid cross-reaction with human DNA background. The developed method increases specificity and sensitivity for pathogen diagnosis, and provides rapid and accurate pathogen detection for rare bacterial DNA in the presence of abundant host DNA.