Enhanced Performance of Next-Generation Sequencing Diagnostics Compared With Standard of Care Microbiological Diagnostics in Patients Suffering From Septic Shock

Objectives: Culture-based diagnostics represent the standard of care in septic patients, but are highly insensitive and in many cases unspecific. We recently demonstrated the general feasibility of next-generation sequencing-based diagnostics using free circulating nucleic acids (cell-free DNA) in plasma samples of septic patients. Within the presented investigation, higher performance of next-generation sequencing-based diagnostics was validated by comparison to matched blood cultures. Design: A secondary analysis of a prospective, observational, single-center study. Setting: Surgical ICU of a university hospital and research laboratory. Patients: Fifty patients with septic shock, 20 uninfected patients with elective surgery as control cohort. Interventions: None. Measurements and Main Results: From 256 plasma samples of 48 septic patients at up to seven consecutive time points within the 28-day observation period, cell-free DNA was isolated and analyzed by next-generation sequencing and relevance scoring. In parallel, results from culture-based diagnostics (e.g., blood culture) were obtained. Plausibility of blood culture and nextgeneration sequencing results as well as adequacy of antibiotic therapy was evaluated by an independent expert panel. In contrast to blood culture with a positivity rate of 33% at sepsis onset, the positivity rate for next-generation sequencing-based pathogen identification was 72%. Over the whole study period, blood culture positivity was 11%, and next-generation sequencing positivity was 71%. Ninety-six percent of positive next-generation sequencing results for acute sepsis time points were plausible and would have led to a change to a more adequate therapy in 53% of cases as assessed by the expert evaluation. Conclusions: Our results show that next-generation sequencingbased analyses of bloodstream infections provide a valuable diagnostic platform for the identification of clinically relevant pathogens with higher sensitivity and specificity than blood culture, indicating that patients might benefit from a more appropriate therapy based on next-generation sequencing-based diagnosis.