Flow Cytometry-Based Quantification of Neutrophil Extracellular Traps Shows an Association with Hypercoagulation in Septic Shock and Hypocoagulation in Postsurgical Systemic Inflammation—A Proof-of-Concept Study

Abstract

This proof-of-concept study aimed to evaluate a novel method of flow cytometry-based quantification of neutrophil extracellular traps (NETs) in septic shock patients and to identify possible interactions between the number of free-circulating NETs and alterations of the coagulatory system. Patients suffering from septic shock, a matched control group (CTRL), and patients suffering from systemic inflammation after cardiac (CABG) or major abdominal surgery (MAS) were enrolled in this prospective proof-of-concept study. Compared to the matched controls, free-circulating NETs were significantly elevated in septic shock and postsurgical patients (data are presented in median (IQR)); septic shock: (2.7 (1.9–3.9); CABG: 2.7 (2.1–3.7); MAS: 2.7 (2.1–3.9); CTRL: 1.6 (1–2); CTRL vs. septic shock: p = 0.001; CTRL vs. CABG: p < 0.001; CTRL vs. MAS: p < 0.001). NETs correlated positively with FIBTEM mean clot firmness (MCF) in septic shock patients (r = 0.37, p < 0.01) while they correlated negatively in surgical patients (CABG: r = −0.28, p < 0.01; MAS: r = −0.25, p = 0.03). Flow-cytometric quantification of NETs showed a significant increase in free-circulating NETs under inflammatory conditions. Furthermore, this study hints to an association of the number of NETs with hypercoagulation in septic shock patients and hypocoagulation in surgery-induced inflammation.

Blood Levels of Free-Circulating Mitochondrial DNA in Septic Shock and Postsurgical Systemic Inflammation and Its Influence on Coagulation: A Secondary Analysis of a Prospective Observational Study

“…This study is a secondary analysis, based on a single-center, prospective, observational proof-of-concept study that included 80 patients at the University Hospital of Giessen [ 8 ]. The local ethics committee approved the primary study, as well as the secondary data analysis (Justus-Liebig-University of Giessen, trial code: 86/18), and both were registered in the German Clinical Trials Register (trial code: DRKS00013584).…”

“…The primary study on which this secondary analysis is based aimed to identify NETs, measured by flow cytometry, as a potential discriminative biomarker between sterile and septic inflammation [ 8 ]. However, although NETs significantly increased after major surgery and during sepsis, the blood levels of free-circulating NETs did not differ between these conditions.…”

“…The goal of this follow-up analysis was to quantify the plasma levels of free-circulating ND1 mtDNA associated with septic shock and surgery-induced systemic inflammation. Furthermore, we aimed to identify any potential in vivo interaction between plasma levels of ND1 mtDNA and the coagulatory system [ 8 , 16 , 17 ].…”

Abdominal Sepsis. Some Genetic-Molecular Mechanisms of Its Occurrence

“…According to frequency of detection, abdominal surgical infection ranks the second position after respiratory tract infections [73]. Abdominal sepsis mortality remains high in 30%, and infectious-toxic shock mortality rises to 80% [68].…”

“…Neutrophils release neutrophil extracellular traps which contain nucleic acids, histones, and granule contents (myeloperoxidase, neutrophil elastase). Neutrophil extracellular traps form web-like formations that trap pathogens, reducing their spread and improvement of neutrophil antimicrobial activity [68]. However, neutrophil extracellular traps that cause an excessive coagulation might lead to disseminated intravascular coagulation [69,70].…”