A Fast PCR Method for Rapid Identification of Infectious Pathogens

Sepsis is an acute and life threatening medical condition characterized by a systemic infection (bacterial, fungal, or viral), inflammatory response and eventual organ dysfunction. Sepsis is associated with high mortality and is a significant driver of healthcare costs in the US and around the world. Patient survival relies heavily on rapid identification of the causative pathogen(s) to facilitate a specific and effective antimicrobial therapy. Historically, the gold standard for pathogen identification continues to be blood culturing, a time intensive process requiring upwards of several days for accurate identification of the microorganism. More recently, molecular diagnostics have emerged as options that take advantages of the polymerase chain reaction (PCR) to amplify the deoxyribonucleic acids (DNA) of microorganisms. Ibis Biosciences’ Bacteria, Antibiotic resistance, and Candida Blood Stream Infection (BAC BSI) assay is a PCR-based technology that conjoins the speed and specificity of PCR with the high resolution sensitivity of electro spray ionization time-of-flight mass spectrometry (ESI-TOF MS) for species identification directly from whole blood samples. The objective of this work reduced the time-to-answer (TTA) through the development of a custom thermocycler and PCR conditions that yielded a 78% reduction in amplification time. Limit of Detection (LoD) was enhanced due to the incorporation of a target enrichment strategy that eliminated factors associated with whole blood samples that adversely affect PCR efficiency.