Molecular Classifiers of Bacterial Infection

Unmet Need

Bacterial infections can lead to various outcomes, with septicemia posing significant morbidity and mortality risks for patients. Septicemia occurs when bacteria enter and spread through the bloodstream, triggering an extreme immune response in the host body. If not promptly and effectively treated, septicemia can result in septic shock and organ failure, which can be fatal in up to half of cases. Blood cultures are currently the standard for diagnosing bloodstream infections, but they have limitations in sensitivity and the speed of providing results. Diagnostic delays and uncertainties can have negative impacts on patient outcomes due to treatment effectiveness and the potential for inappropriate antibiotic usage. Research suggests that an alternative diagnostic approach could involve utilizing the host’s immune response to identify the infecting pathogen. There is a need for a new, quicker approach capable of distinguishing between the major pathogens responsible for bacterial infections.

Technology

Duke researchers have developed a new method for identifying biomarkers that are associated with specific types of bacteria. This innovative approach is intended to serve as an alternative diagnostic tool to rapidly identify patients suffering from bacterial infections. The researchers used both gram-positive and gram-negative bacteria to create a classifier that can distinguish between infected and healthy individuals. The classifiers are derived from changes in gene expression in peripheral blood cells, specifically related to the immune response of the infected individuals. To validate their classifiers, the researchers first studied mice with various types and levels of bacterial infections to identify the gene expression patterns in immune cells. After defining the characteristics of different infection types, they validated their findings in a group of human subjects. This research was the first to identify specific genetic biomarkers that are characteristic of two different types of bacterial infections.

Other Applications

This technology could also be used to monitor the progression of patients' immune response against bacterial infections.  

Advantages

• Faster accurate approach to differentiate between pathogens causing bacterial infection.

• Biomarkers detected in this invention are more sensitive than the current diagnostic standard for bacterial infection in identifying disease states.

• Enhancement of patient outcomes by allowing optimal treatment more rapidly.