Combination of thrombin-antithrombin complex, plasminogen activator inhibitor-1, and protein C activity for early identification of severe coagulopathy in initial phase of sepsis: a prospective observational study

Endothelial cell dynamics in sepsis-induced acute lung injury and acute respiratory distress syndrome: pathogenesis and therapeutic implications

Sepsis, a prevalent critical condition in clinics, continues to be the leading cause of death from infections and a global healthcare issue. Among the organs susceptible to the harmful effects of sepsis, the lungs are notably the most frequently affected. Consequently, patients with sepsis are predisposed to developing acute lung injury (ALI), and in severe cases, acute respiratory distress syndrome (ARDS). Nevertheless, the precise mechanisms associated with the onset of ALI/ARDS remain elusive. In recent years, there has been a growing emphasis on the role of endothelial cells (ECs), a cell type integral to lung barrier function, and their interactions with various stromal cells in sepsis-induced ALI/ARDS. In this comprehensive review, we summarize the involvement of endothelial cells and their intricate interplay with immune cells and stromal cells, including pulmonary epithelial cells and fibroblasts, in the pathogenesis of sepsis-induced ALI/ARDS, with particular emphasis placed on discussing the several pivotal pathways implicated in this process. Furthermore, we discuss the potential therapeutic interventions for modulating the functions of endothelial cells, their interactions with immune cells and stromal cells, and relevant pathways associated with ALI/ARDS to present a potential therapeutic strategy for managing sepsis and sepsis-induced ALI/ARDS.

Clinical value of TAT, PIC and t-PAIC as predictive markers for severe sepsis in pediatric patients

Objective

Sepsis in pediatric patients can progress to severe sepsis, and identifying biomarkers of this progression may permit timely intervention to prevent it. This study aimed to investigate the ability of thrombin-antithrombin complex (TAT), α2-plasmininhibitor-plasmin complex (PIC) and tissue-type plasminogen activator-inhibitor complex (t-PAIC) to predict severe sepsis in pediatrics early.

Methods

148 eligible pediatric sepsis patients were enrolled in this study, and were then divided into those who progressed to severe sepsis (n = 50) or not (n = 98). Serum levels of TAT, PIC, and t-PAIC were analysed, and simplified pediatric critical illness score (PCIS) and DIC score were calculated on the day of pediatric sepsis diagnosis.

Results

Compared with sepsis patients, severe sepsis patients had higher levels of TAT, PIC and t-PAIC. Correlation analysis revealed that TAT, PIC and t-PAIC were significantly correlated with simplified PCIS and DIC score. ROC curve analysis suggested that TAT, PIC and t-PAIC could serve as biomarkers for predicting severe sepsis with the AUC up to 0.862, 0.759 and 0.851, respectively. Stratified analysis demonstrated that the patients with increased levels of TAT, PIC and t-PAIC had worse illness severity and clinical outcome. Univariate logistic regression analysis revealed that TAT, PIC and t-PAIC were all risk factors for severe sepsis, yet only TAT and t-PAIC were independent risk factors in multivariate model.

Conclusions

TAT, PIC and t-PAIC could serve as biomarkers for predicting severe sepsis, and correlated with illness severity in pediatrics, what's more, serum levels of TAT and t-PAIC may be independent risk factors for pediatric severe sepsis.

Characterization and Usefulness of Clot-Fibrinolysis Waveform Analysis in Critical Care Patients with Enhanced or Suppressed Fibrinolysis

INTRODUCTION

 Recently, clot-fibrinolysis waveform analysis (CFWA), which is a coagulation and fibrinolysis global assay based on assessing the activated partial thromboplastin time with tissue-type plasminogen activator, was developed. This study aimed to investigate the characteristics of CFWA using plasma samples from patients in the critical care unit.

MATERIALS AND METHODS

 The fibrinolysis times using CFWA were measured in 298 plasma samples. These samples were divided into three groups based on the reference interval (RI) of fibrinolysis time using CFWA: shortened group, less than RI; within group, within RI; prolonged group, more than RI. The coagulation and fibrinolysis markers, including D-dimer, plasmin-α2 plasmin inhibitor complex (PIC), fibrin monomer complex (FMC), plasmin-α2 plasmin inhibitor (α2-PI), plasminogen (Plg), and fibrinogen (Fbg) were analyzed and compared among the three groups.

RESULTS

 The FMC level decreased in the order of shortened, within, and prolonged groups, and the decrease was statistically significant among all three group pairs. The opposite tendency was observed for Fbg and fibrinolysis-related markers of α2-PI and Plg, and significant differences were recognized in all pair comparisons except for between within and prolonged groups in Plg. The mean values of the fibrinolysis markers D-dimer and PIC in all three groups were higher than the cut-off values, and the PIC value differed significantly between the within and prolonged groups.

CONCLUSION

 The fibrinolysis reaction was detected in all three groups, but the status differed. CFWA has the potential to reflect the fibrinolysis status in one global assay.

Development of early prediction model of in-hospital cardiac arrest based on laboratory parameters

BACKGROUND

In-hospital cardiac arrest (IHCA) is an acute disease with a high fatality rate that burdens individuals, society, and the economy. This study aimed to develop a machine learning (ML) model using routine laboratory parameters to predict the risk of IHCA in rescue-treated patients.

METHODS

This retrospective cohort study examined all rescue-treated patients hospitalized at the First Medical Center of the PLA General Hospital in Beijing, China, from January 2016 to December 2020. Five machine learning algorithms, including support vector machine, random forest, extra trees classifier (ETC), decision tree, and logistic regression algorithms, were trained to develop models for predicting IHCA. We included blood counts, biochemical markers, and coagulation markers in the model development. We validated model performance using fivefold cross-validation and used the SHapley Additive exPlanation (SHAP) for model interpretation.

RESULTS

A total of 11,308 participants were included in the study, of which 7779 patients remained. Among these patients, 1796 (23.09%) cases of IHCA occurred. Among five machine learning models for predicting IHCA, the ETC algorithm exhibited better performance, with an AUC of 0.920, compared with the other four machine learning models in the fivefold cross-validation. The SHAP showed that the top ten factors accounting for cardiac arrest in rescue-treated patients are prothrombin activity, platelets, hemoglobin, N-terminal pro-brain natriuretic peptide, neutrophils, prothrombin time, serum albumin, sodium, activated partial thromboplastin time, and potassium.

CONCLUSIONS

We developed a reliable machine learning-derived model that integrates readily available laboratory parameters to predict IHCA in patients treated with rescue therapy.

Clinicopathologic features and prognosis of 71 patients with gastric cancer and disseminated intravascular coagulation

Background

Gastric cancer consists of solid tumors with a tendency for disseminated intravascular coagulation (DIC). DIC is rare in patients with stomach cancer, and there have been few studies on this condition. We aimed to perform comprehensive analyses of the prognosis and clinicopathologic characteristics of stomach cancer patients with DIC.

Methods

Between June 2006 and March 2020, 14,016 patients at Fujian Cancer Hospital were diagnosed with stomach cancer. We reviewed their medical records and found that 105 of these patients were diagnosed with DIC. After excluding patients who were lost to follow-up, 71 patients with DIC remained. The clinical data were retrospectively analyzed to observe clinical characteristics and prognostic factors, and the Kaplan-Meier survival analysis was performed. Prognostic variables were investigated by the Cox proportional hazards method.

Results

The median age was 54 (range, 21-83) years, and 38 patients (53.5%) were male. The histological category was poorly differentiated gastric cancer in 58 patients (81.7%). Eleven patients (15.5%) developed DIC after curative gastric resection. Sixty patients (84.5%) had DIC at the initial presentation of gastric cancer or developed DIC when the tumor progressed during treatment. Fifty-one patients (71.8%) had bleeding symptoms, and 43 (60.6%) patients had comorbidities at the time of DIC diagnosis. Among the 71 patients, 42 (59.2%) had multiple metastatic patterns. Twenty-one (29.6%) patients received chemotherapy. The median overall survival (OS) was 57.0 days (95% confidence interval [CI] [33.1-80.9] days). Tumor status (P = 0.000) and treatment (P = 0.003) were found to be significant variables associated with OS by univariate analysis. Multivariate analysis showed that tumor status (P = 0.000) and treatment (P = 0.000) had independent effects on OS.

Conclusions

Gastrointestinal bleeding, multiple metastatic patterns and comorbidities at diagnosis with DIC are common in patients with gastric cancer complicated with DIC. Patients with poorly differentiated gastric cancer are more likely to develop DIC. Treatment and tumor status are separate risk variables for the survival of gastric cancer patients with DIC.DIC patients without tumors have a good prognosis and can be cured by appropriate etiological correction and symptomatic treatment. Chemotherapy can improve the prognosis of DIC patients with tumors.

A Multilayered Imaging and Microfluidics Approach for Evaluating the Effect of Fibrinolysis in Staphylococcus aureus Biofilm Formation

The recognition of microbe and extracellular matrix (ECM) is a recurring theme in the humoral innate immune system. Fluid-phase molecules of innate immunity share regulatory roles in ECM. On the other hand, ECM elements have immunological functions. Innate immunity is evolutionary and functionally connected to hemostasis. Staphylococcus aureus (S. aureus) is a major cause of hospital-associated bloodstream infections and the most common cause of several life-threatening conditions such as endocarditis and sepsis through its ability to manipulate hemostasis. Biofilm-related infection and sepsis represent a medical need due to the lack of treatments and the high resistance to antibiotics. We designed a method combining imaging and microfluidics to dissect the role of elements of the ECM and hemostasis in triggering S. aureus biofilm by highlighting an essential role of fibrinogen (FG) in adhesion and formation. Furthermore, we ascertained an important role of the fluid-phase activation of fibrinolysis in inhibiting biofilm of S. aureus and facilitating an antibody-mediated response aimed at pathogen killing. The results define FG as an essential element of hemostasis in the S. aureus biofilm formation and a role of fibrinolysis in its inhibition, while promoting an antibody-mediated response. Understanding host molecular mechanisms influencing biofilm formation and degradation is instrumental for the development of new combined therapeutic approaches to prevent the risk of S. aureus biofilm-associated diseases.

PAI-1 genetic polymorphisms influence septic patients' outcomes by regulating neutrophil activity

BACKGROUND

Plasminogen activator inhibitor-1 (PAI-1) plays an important role in the pathophysiology of sepsis, but the exact mechanism remains debatable. In this study, we investigated the associations among the serum levels of PAI-1, the incidence of 4G/5G promoter PAI-1 gene polymorphisms, immunological indicators, and clinical outcomes in septic patients.

METHODS

A total of 181 patients aged 18-80 years with sepsis between November 2016 and August 2018 in the intensive care unit in the Xinhua Hospital were recruited in this retrospective study, with 28-day mortality as the primary outcome. The initial serum level of PAI-1 and the presence of rs1799768 single nucleotide polymorphisms (SNPs) were examined. Univariate logistic regression and multivariate analyses were performed to determine the factors associated with different genotypes of PAI-1, serum level of PAI-1, and 28-day mortality.

RESULTS

The logistic analysis suggested that a high serum level of PAI-1 was associated with the rs1799768 SNP of PAI-1 (4G/4G and 4G/5G) (Odds ratio [OR]: 2.49; 95% confidence interval [CI]: 1.09, 5.68). Furthermore, a high serum level of PAI-1 strongly influenced 28-day mortality (OR 3.36; 95% CI 1.51, 7.49). The expression and activation of neutrophils (OR 0.96; 95% CI 0.93, 0.99), as well as the changes in the expression patterns of cytokines and chemokine-associated neutrophils (OR: 1.00; 95% CI: 1.00, 1.00), were both regulated by the genotype of PAI-1.

CONCLUSIONS

Genetic polymorphisms of PAI-1 can influence the serum levels of PAI-1, which might contribute to mortality by affecting neutrophil activity. Thus, patients with severe sepsis might clinically benefit from enhanced neutrophil clearance and the resolution of inflammation via the regulation of PAI-1 expression and activity.

Biomarkers of endothelial activation and inflammation in dogs with organ dysfunction secondary to sepsis

Introduction

Alteration in endothelial function during sepsis is thought to play a key role in the progression of organ failure. We herein compared plasma concentrations of endothelial activation biomarkers vascular endothelial growth factor (VEGF), hyaluronan (HA), plasminogen activator inhibitor-1 (PAI-1) and von Willebrand factor (vWF), as well as inflammatory mediator concentrations (IL-6, IL-8, IL-10, C-reactive protein and monocyte chemoattractant protein-1) in dogs with sepsis to healthy dogs.

Methods

This study was a multicenter observational clinical trial conducted at two university teaching hospitals from February 2016 until July 2017. The study included 18 client-owned dogs hospitalized with sepsis and at least one distant organ dysfunction, as well as 20 healthy dogs. Plasma biomarker concentrations were measured using ELISA. Severity of illness in dogs with sepsis was calculated using the 5-variable acute physiologic and laboratory evaluation (APPLEFAST) score. Biomarker concentrations were compared between septic and healthy dogs using linear models.

Results

Septic peritonitis was the most frequent source of sepsis (11/18; 61%), followed by pneumonia (4/18; 22%). Ten dogs (56%) had only 1 organ dysfunction, whereas 3 dogs (17%) had 2, 3 (17%) had 3, 1 (6%) had 4 and 1 (6%) had 5 organ dysfunctions. The median APPLEFAST score in the septic dogs was 28.5 (Q1-Q3, 24-31). Mean plasma concentrations of all endothelial and inflammatory biomarkers, except vWF, were higher in the sepsis cohort than in controls. The mean endothelial biomarker concentrations in the septic cohort ranged from ~2.7-fold higher for HA (difference in means; 118.2 ng/mL, 95% credible limit; 44.5-221.7) to ~150-fold for VEGF (difference in means; 76.6 pg./mL, 95% credible limit; 33.0-143.4), compared to the healthy cohort. Fifteen dogs with sepsis (83%) died; 7 (46%) were euthanized and 8 (53%) died during hospitalization.

Conclusion

Dogs with naturally occurring sepsis and organ dysfunction had higher mean concentrations of biomarkers of endothelial activation and inflammation compared to healthy dogs, broadening our understanding of the pathophysiology of sepsis secondary to endothelial dysfunction.

THE EFFECTS OF DNASE I AND LOW-MOLECULAR-WEIGHT HEPARIN IN A MURINE MODEL OF POLYMICROBIAL ABDOMINAL SEPSIS

ABSTRACT

Introduction: Cell-free DNA (CFDNA) has emerged as a prognostic biomarker in patients with sepsis. Circulating CFDNA is hypothesized to be associated with histones in the form of nucleosomes. In vitro, DNA activates coagulation and inhibits fibrinolysis, whereas histones activate platelets and are cytotoxic to endothelial cells. Previous studies have targeted CFDNA or histones in animal models of sepsis using DNase I or heparins, respectively, which has reduced inflammatory and thrombosis markers, thereby improving survival. In this study, we explored the possibility that the combination of DNase I and a low-molecular weight heparin (LMWH) may be a better therapeutic approach than monotherapy in a murine model of abdominal sepsis. Methods: C57Bl/6 mice (8-12 weeks old, both sexes) were subjected to either cecal ligation and puncture or sham surgery. Mice were given antibiotics, fluids, and either saline, DNase I (intraperitoneally, 20 mg/kg/8 h), LMWH (dalteparin, subcutaneously 500 IU/kg/12 h), or a combination of both (n = 12-31). Mice were monitored over 72 h for survival. Organs and blood were harvested for analysis. Levels of LMWH, CFDNA, IL-6, citrullinated histone-H3, thrombin-antithrombin complexes, and protein C were measured in plasma. Results: Administration of either DNase I (81.8%) or LMWH (83.3%, prophylactic range of 0.12 ± 0.07 IU/mL achieved) improved the survival of septic mice compared with saline- (38.7%) and combination-treated mice (48.8%, P < 0.05). Combination-treated mice also showed a small but insignificant improvement in survival compared with saline-treated cecal ligation and puncture mice. Monotherapies may be improving survival by reducing blood bacterial loads, citrullinated histone-H3, and thrombin-antithrombin complexes, and improving protein C levels. Conclusions: Compared with saline- and combination-treated mice, administration of monotherapies to septic mice improved survival. These findings suggest that there may be a negative drug-drug interaction between DNase I and LMWH when DNase I is administered intraperitoneally in a murine model of polymicrobial abdominal sepsis.

The Role of Plasminogen Activator Inhibitor 1 in Predicting Sepsis-Associated Liver Dysfunction: An Observational Study

Sepsis-associated liver dysfunction (SALD) is associated with a poor prognosis and increased mortality in the intensive care unit. Bilirubin is one of the components of Sequential Organ Failure Assessment used in Sepsis-3 criteria. Hyperbilirubinemia is a late and non-specific symptom of liver dysfunction. This study aimed to identify plasma biomarkers that could be used for an early diagnosis of SALD. This prospective, observational study was conducted on a group of 79 patients with sepsis and septic shock treated in the ICU. Plasma biomarkers-prothrombin time, INR, antithrombin III, bilirubin, aspartate transaminase (AST), alanine transaminase, alkaline phosphatase, gamma glutamyl transferase, albumin, endothelin-1, hepcidin, plasminogen activator inhibitor-1 (PAI-1), thrombin-antithrombin complex, and interferon-gamma inducible protein (10 kDa) were analysed. Plasma samples were obtained within 24 h after having developed sepsis/septic shock. Enrolled patients were followed for 14 days for developing SALD and 28 days for overall survival. A total of 24 patients (30.4%) developed SALD. PAI-1 with a cut-off value of 48.7 ng/mL was shown to be a predictor of SALD (AUC = 0.671, sensitivity 87.3%, and specificity 50.0%) and of 28-day survival in patients with sepsis/septic shock (p = 0.001). Measuring PAI-1 serum levels at the onset of sepsis and septic shock may be useful in predicting the development of SALD. This should be verified in multicenter prospective clinical trials.

Communication from the Scientific Standardization Committees of the International Society on Thrombosis and Haemostasis on vascular endothelium-related biomarkers in disseminated intravascular coagulation

Disseminated intravascular coagulation (DIC) is not a disease criterion but a pathomechanistic process that accompanies various underlying diseases. According to the International Society on Thrombosis and Haemostasis definition, endothelial injury is an essential component in addition to systemic coagulation activation. Despite this definition, current diagnostic criteria for DIC do not include biomarkers for vascular endothelial injury. Endothelial cells are critical for hemostatic regulation because they produce various antithrombotic substances and express anticoagulant factors at the same time as facilitating coagulation, inflammatory reactions, platelet aggregation, and fibrinolysis with acute injury. Endothelial cells also exhibit various receptors, adhesion molecules, and the critical role of glycocalyx that regulates cellular interactions in thromboinflammation. For clinicians, biomarkers suitable for assessing endothelial injury are not readily available. Although we still do not have ideal biomarkers, antithrombin activity and von Willebrand factor can be candidates for the endothelium-related markers because those reflect the severity and are available in most clinical settings. Further, the dysfunction of endothelial cell in DIC arising from various underlying diseases is likely highly variable. For example, the involvement of endothelial dysfunction is significant in sepsis-induced coagulopathy, while moderate in trauma-induced coagulopathy, and variable in hematologic malignancy-associated coagulopathy. Because of the complexity of disease status associated with DIC, further research searching clinically available endothelium-related biomarkers is expected to establish individualized diagnostic criteria and potential therapeutic approaches.

Effect of plasma thrombin-antithrombin complex on ischemic stroke: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Thrombin-antithrombin complex (TAT) is a prethrombotic marker, and its application in ischemic stroke is still uncertain. The purpose of this systematic review and meta-analysis is to evaluate the relationship between plasma TAT and ischemic stroke base on the current evidence.

METHODS

A systematic literature search was conducted for searching the relative studies that investigated the association of TAT and ischemic stroke in PubMed, EMBASE, and Cochrane library databases. Mean difference and 95% confidence interval as the effect sizes were synthesized by random effects model in Review Manager (RevMan) Version 5.4. The heterogeneity was investigated using the chi-square test and the possible sources of heterogeneity were explored by sensitivity analysis and meta-regression. The publication bias was estimated by Egger's tests.

RESULTS

A total of 12 eligible studies were included involving 1431 stroke cases and 532 healthy controls, of which six studies were eventually included in the meta-analysis. Plasma TAT in patients with ischemic stroke was significantly higher than that in healthy controls (MD 5.31, 95% CI = 4.12-6.51, P < 0.0001, I² = 97.8%). There is a difference of TAT level in the same period among cardioembolic, lacunar, and atherothrombotic stroke (all P < 0.0001), in which the cardioembolic stroke with the highest level. Meanwhile, it is significant of TAT levels among various phases of cardioembolic stroke and the acute phase are markedly elevated (MD 7.75, 95CI%, 6.07-9.43, P < 0.001). However, no difference was found in the atherothrombotic (P = 0.13) and lacunar stroke (P = 0.34). Besides, the higher TAT level is closely related to the poor prognosis of patients with ischemic stroke, including higher recurrence, mortality, unfavorable recovery (modified Rankin scale > 2), and poor revascularization.

CONCLUSIONS

This study suggested that plasma TAT levels are different in ischemic stroke subtypes, which are closely associated with the progression and might have an effect on the prognosis.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD: 42021248787.

Fibroblast growth factor 2 (FGF2) ameliorates the coagulation abnormalities in sepsis

BACKGROUND

Sepsis is defined as a life-threatening organ dysfunction caused by dysregulation of the host response to infection. There is still a lack of specific treatment for sepsis. Here, we report that Fibroblast growth factor-2 (FGF2) can reduce the mortality of sepsis by ameliorating the coagulation abnormalities.

METHODS

FGF2 was intraperitoneally injected into septic mice induced by lipopolysaccharide (LPS) and then assessed for coagulation response, organ damage and survival. RAW264.7 cells with or without FGF2 pretreating were exposed to LPS, and then changes in coagulation related factors expression and signaling were tested.

RESULTS

The findings showed that intraperitoneal injection of FGF2 inhibited coagulation activity, reduced lung and liver damage, and increased survival in septic mice. In RAW264.7 cells, LPS upregulated the expression of tissue factor (TF) and plasminogen activator inhibitor-1 (PAI-1); however, pretreatment with FGF2 prevented this upregulation, while FGF2 knockdown exacerbated TF upregulation. Moreover, FGF2 suppressing the AKT/mTOR/S6K1 signaling pathway in septic mice and RAW264.7 cells stimulated by LPS.

CONCLUSIONS

This study revealed a therapeutic role of FGF2 in ameliorating the coagulation abnormalities during sepsis.

Sepsis-Induced Coagulopathy: An Update on Pathophysiology, Biomarkers, and Current Guidelines

Significant cross talk occurs between inflammation and coagulation. Thus, coagulopathy is common in sepsis, potentially aggravating the prognosis. Initially, septic patients tend to exhibit a prothrombotic state through extrinsic pathway activation, cytokine-induced coagulation amplification, anticoagulant pathways suppression, and fibrinolysis impairment. In late sepsis stages, with the establishment of disseminated intravascular coagulation (DIC), hypocoagulability ensues. Traditional laboratory findings of sepsis, including thrombocytopenia, increased prothrombin time (PT) and fibrin degradation products (FDPs), and decreased fibrinogen, only present late in the course of sepsis. A recently introduced definition of sepsis-induced coagulopathy (SIC) aims to identify patients at an earlier stage when changes to coagulation status are still reversible. Nonconventional assays, such as the measurement of anticoagulant proteins and nuclear material levels, and viscoelastic studies, have shown promising sensitivity and specificity in detecting patients at risk for DIC, allowing for timely therapeutic interventions. This review outlines current insights into the pathophysiological mechanisms and diagnostic options of SIC.

Clinical study on the feasibility of new thrombus markers in predicting massive cerebral infarction

Objective

This study investigated the diagnostic performance of the thrombin-antithrombin complex (TAT), plasmin-α2 plasmin inhibitor complex (PIC), tissue plasminogen activator-plasminogen activator inhibitor complex (t-PAIC), and thrombomodulin (TM) in the early identification of massive cerebral infarction.

Method

A total of 423 patients with cerebral infarction confirmed by imaging examination were divided into the massive cerebral infarction (MCI) group and the non-massive cerebral infarction (NMCI) group. TAT, PIC, t-PAIC, and TM were measured immediately after admission. The diagnostic performance was analyzed by the receiver characteristic operating curve (ROC).

Result

The median plasma concentrations of TAT, PIC, and t-PAIC in patients with MCI at early onset were 5.10 ng/ml, 1.11 μg/ml, and 8.80 ng/ml, respectively, which were higher than those in patients with NMCI (2.20 ng/ml, 0.59 μg/ml, and 7.35 ng/ml), and the difference was statistically significant (P < 0.001). TAT was shown to be an independent risk factor for the development of massive cerebral infarction by a multivariate logistic regression analysis (OR = 1.138). A ROC curve analysis showed that PIC had the best performance in identifying MCI at an early stage (AUC = 82.8%), with a sensitivity of 80.7% and a specificity of 76.2% when the PIC concentration was ≥0.8 μg/ml; TAT had the highest specificity in identifying MCI, with a specificity of 80.6% when the TAT concentration was ≥3.97 ng/ml.

Conclusion

The detection of PIC, TAT, t-PAIC, and TM is a comprehensive assessment of vascular endothelial damage and activation of the coagulation and fibrinolytic systems and has diagnostic value for early identification of patients with MCI, which, together with its ease of detection, can be used as a plasma marker for early identification of large vessel occlusion.

Fibrinogen Is Associated with Prognosis of Critically Ill Patients with Sepsis: A Study Based on Cox Regression and Propensity Score Matching

Introduction

Sepsis is a common syndrome in critically ill patients. Fibrinogen was reported to be associated with the prognosis of sepsis patients.

Materials and Methods

Data was acquired from Multiparameter Intelligent Monitoring in Intensive Care Database IV (MIMIC-IV) version 1.0. Cox proportional hazards regression was utilized to estimate the relationship between fibrinogen and inhospital mortality. The cumulative incidence of mortality by fibrinogen level was estimated through the Kaplan-Meier curve. Restricted cubic spline (RCS) was used to assess nonlinear relationship. Subgroup analysis was also conducted to evaluate the robustness of the association between fibrinogen and inhospital mortality. Propensity score matching (PSM) was applied to adjust for confounding factors.

Results

A total of 3365 patients, including 2031 survivors and 1334 nonsurvivors, were enrolled in our study. The survivors had a significantly elevated levels of fibrinogen compared with the deceased. The elevated level of fibrinogen was significantly associated with a decrease in mortality in multivariate Cox regression before and after PSM (HR 0.66, P < 0.001 and HR 0.73, P < 0.001, respectively). RCS showed a nearly linear relationship. Subgroup analysis demonstrated the robustness of the association in most subpopulations. However, the association between decreased levels of fibrinogen and increased inhospital mortality was denied after PSM.

Conclusion

The elevated level of fibrinogen hints at better overall survival in critically ill patients with sepsis. Decreased levels of fibrinogen may be of little value in identifying patients with a high risk of death.

Liang-Ge Decoction Ameliorates Coagulation Dysfunction in Cecal Ligation and Puncture-Induced Sepsis Model Rats through Inhibiting PAD4-Dependent Neutrophil Extracellular Trap Formation

Liang-Ge (LG) decoction could ameliorate coagulation dysfunction in septic model rats. However, the mechanism of LG in treating sepsis still needs to be clarified. Our current study established a septic rat model to evaluate the effect of LG on coagulation dysfunction in septic rats first. Second, we investigated the effect of LG on NET formation in septic rats. Finally, NETs and PAD4 inhibitors were further used to clarify if LG could improve the mechanism of sepsis coagulation dysfunction by inhibiting NET formation. Our findings indicated that treatment with LG improved the survival rate, reduced inflammatory factor levels, enhanced hepatic and renal function, and reduced pathological changes in rats with sepsis. LG could also alleviate coagulation dysfunction in septic model rats. Besides, LG treatment reduced NETs formation and decreased PAD4 expression in neutrophiles. In addition, LG treatment showed a similar result in comparison to the treatment with either NET inhibitors or PAD4 inhibitors alone. In conclusion, this study confirmed that LG has therapeutic effects on septic rats. Furthermore, the improvement of coagulation dysfunction in septic rats by LG was achieved through inhibiting PAD4-mediated NET formation.

Potential Biomarkers for Early Diagnosis, Evaluation, and Prognosis of Sepsis-Induced Coagulopathy

Sepsis-induced coagulopathy (SIC) is a life-threatening complication characterized by the systemic activation of coagulation in sepsis. The diagnostic criteria of SIC consist of three items, including Sequential Organ Failure Assessment (SOFA) score, platelet count, and prothrombin time (PT)-international normalized ratio (INR). SIC has a high prevalence and it can lead to a higher mortality rate and longer length of hospital and ICU stay. Thus, the early detection of SIC is extremely important. It is unfortunate that there is still no precise biomarker for early diagnosis and assessment of the prognosis of SIC. We reviewed the current literature and discovered that some potential biomarkers, such as soluble thrombomodulin (sTM), thrombin-antithrombin complex (TAT), tissue plasminogen activator-inhibitor complex (t-PAIC), α2-plasmin inhibitor-plasmin complex (PIC), C-type lectin-like receptor 2 (CLEC-2), neutrophil extracellular traps (NETs), prothrombin fragment 1.2 (F1.2), Angiopoietin-2 (Ang-2), plasminogen activator inhibitor-1 (PAI-1), and tissue inhibitor of metalloproteinase-1 (TIMP-1) may be useful for early diagnosis, evaluation, and prognosis of SIC. Early initiation of treatment without missing any therapeutic opportunities may improve SIC patients' prognosis. Further large-scale clinical studies are still needed to confirm the role of these biomarkers in the diagnosis and prognosis assessment of SIC.

Salvianolic acid A alleviates lipopolysaccharide-induced disseminated intravascular coagulation by inhibiting complement activation

Introduction

Disseminated intravascular coagulation (DIC) is a syndrome characterized by coagulopathy, microthrombus, and multiple organ failure. The complement system in DIC is overactivated, and the functions of complement and coagulation pathways are closely related. Our previous screening revealed that salvianolic acid A (SAA) has anti-complement activity. The hyper-activated complement system was involved in the lipopolysaccharide (LPS) induced DIC in rats. The effects of SAA anti-complement action on LPS-induced DIC in rats were investigated.

Methods

The complement activity of the classical pathway and alternative pathway was detected through an in vitro hemolysis assay. The binding sites of SAA and complement C3b were predicted by molecular docking. LPS-induced disseminated coagulation experiments were performed on male Wistar rats to assess coagulation function, complement activity, inflammation, biochemistry, blood routine, fibrinolysis, and survival.

Results

SAA had an anti-complement activity in vivo and in vitro and inhibited the complement activation in the classical and alternative pathway of complement. The infusion of LPS into the rats impaired the coagulation function, increased the plasma inflammatory cytokine level, complemented activation, reduced the clotting factor levels, fibrinogen, and platelets, damaged renal, liver, and lung functions, and led to a high mortality rate (85%). SAA treatment of rats inhibited complement activation and attenuated the significant increase in D-dimer, interleukin-6, alanine aminotransferase, and creatinine. It ameliorated the decrease in plasma levels of fibrinogen and platelets and reversed the decline in activity of protein C and antithrombin III. The treatment reduced kidney, liver, and lung damage, and significantly improved the survival rate of rats (46.2 and 78.6% for the low- and high-dose groups, respectively).

Conclusion

SAA reduced LPS-induced DIC by inhibiting complement activation. It has considerable potential in DIC treatment.

Assessment of coagulation markers, serum zinc and copper in children with beta-thalassemia major in Egypt

BACKGROUND

Thalassemia is one of the commonest single gene disorders usually associated with many complications. Coagulation changes as well as trace elements levels alterations have been described in children with β thalassemia. Activation of coagulation can be assessed by measuring thrombin-antithrombin (TAT) complex, plasmin-antiplasmin (PAP) complex and β-thromboglobulin (β-TG).

METHODS

A total of 200 children and adolescents were enrolled in the study; 100 were from the Al-Azhar University hospital's pediatric hematology clinic diagnosed as thalassemia major, while the other 100 were apparently healthy volunteers who acted as the control group. Complete blood count, liver function test, kidney function tests, TAT complex, PAP complex, β-TG as indicators of coagulation changes, serum zinc and copper were performed on all participants.

RESULTS

Significantly higher levels of TAT complex, PAP complex and β-TG in thalassemia children than the controls. Decreased serum zinc and increased serum copper levels in thalassemia children compared to the controls. A negative correlation was observed between the serum level of TAT and hemoglobin level, besides the negative correlation of TAT complex and β-TG with the serum zinc.

CONCLUSION

Thalassemia major was associated with increased serum level of coagulation activation markers, increased serum copper while decreased serum zinc.

Extracellular Histones Trigger Disseminated Intravascular Coagulation by Lytic Cell Death

Histones are cationic nuclear proteins that are essential for the structure and functions of eukaryotic chromatin. However, extracellular histones trigger inflammatory responses and contribute to death in sepsis by unknown mechanisms. We recently reported that inflammasome activation and pyroptosis trigger coagulation activation through a tissue-factor (TF)-dependent mechanism. We used a combination of various deficient mice to elucidate the molecular mechanism of histone-induced coagulation. We showed that histones trigger coagulation activation in vivo, as evidenced by coagulation parameters and fibrin deposition in tissues. However, histone-induced coagulopathy was neither dependent on intracellular inflammasome pathways involving caspase 1/11 and gasdermin D (GSDMD), nor on cell surface receptor TLR2- and TLR4-mediated host immune response, as the deficiency of these genes in mice did not protect against histone-induced coagulopathy. The incubation of histones with macrophages induced lytic cell death and phosphatidylserine (PS) exposure, which is required for TF activity, a key initiator of coagulation. The neutralization of TF diminished the histone-induced coagulation. Our findings revealed lytic cell death as a novel mechanism of histone-induced coagulation activation and thrombosis.

Biomarkers Predicting Tissue Pharmacokinetics of Antimicrobials in Sepsis: A Review

The pathophysiology of sepsis alters drug pharmacokinetics, resulting in inadequate drug exposure and target-site concentration. Suboptimal exposure leads to treatment failure and the development of antimicrobial resistance. Therefore, we seek to optimize antimicrobial therapy in sepsis by selecting the right drug and the correct dosage. A prerequisite for achieving this goal is characterization and understanding of the mechanisms of pharmacokinetic alterations. However, most infections take place not in blood but in different body compartments. Since tissue pharmacokinetic assessment is not feasible in daily practice, we need to tailor antibiotic treatment according to the specific patient’s pathophysiological processes. The complex pathophysiology of sepsis and the ineffectiveness of current targeted therapies suggest that treatments guided by biomarkers predicting target-site concentration could provide a new therapeutic strategy. Inflammation, endothelial and coagulation activation markers, and blood flow parameters might be indicators of impaired tissue distribution. Moreover, hepatic and renal dysfunction biomarkers can predict not only drug metabolism and clearance but also drug distribution. Identification of the right biomarkers can direct drug dosing and provide timely feedback on its effectiveness. Therefore, this might decrease antibiotic resistance and the mortality of critically ill patients. This article fills the literature gap by characterizing patient biomarkers that might be used to predict unbound plasma-to-tissue drug distribution in critically ill patients. Although all biomarkers must be clinically evaluated with the ultimate goal of combining them in a clinically feasible scoring system, we support the concept that the appropriate biomarkers could be used to direct targeted antibiotic dosing.

The prognostic utility of protein C as a biomarker for adult sepsis: a systematic review and meta-analysis

Background

Sepsis, the dysregulated host response to infection, triggers abnormal pro-coagulant and pro-inflammatory host responses. Limitations in early disease intervention highlight the need for effective diagnostic and prognostic biomarkers. Protein C’s role as an anticoagulant and anti-inflammatory molecule makes it an appealing target for sepsis biomarker studies. This meta-analysis aims to assess the diagnostic and prognostic value of protein C (PC) as a biomarker for adult sepsis.

Methods

We searched MEDLINE, PubMed, EMBASE, CINAHL and Cochrane Library from database inception to September 12, 2021. We included prospective observational studies of (1) adult patients (> 17) with sepsis or suspicion of sepsis that; (2) measured PC levels with 24 h of study admission with; and (3) the goal of examining PC as a diagnostic or prognostic biomarker. Two authors screened articles and conducted risk of bias (RoB) assessment, using the Quality in Prognosis Studies (QUIPS) and the Quality Assessment in Diagnostic Studies-2 (QUADAS-2) tools. If sufficient data were available, meta-analysis was conducted to estimate the standardized mean difference (SMD) between patient populations.

Results

Twelve studies were included, and 8 were synthesized for meta-analysis. Pooled analysis demonstrated moderate certainty of evidence that PC levels were less reduced in sepsis survivors compared to non-survivors (6 studies, 741 patients, SMD = 0.52, 95% CI 0.24–0.81, p = 0.0003, I² = 55%), and low certainty of evidence that PC levels were less reduced in septic patients without disseminated intravascular coagulation (DIC) compared to those with DIC (3 studies, 644 patients, SMD = 0.97, 95% CI 0.62–1.32, p < 0.00001, I² = 67%). PC could not be evaluated as a diagnostic tool due to heterogeneous control populations between studies.

Conclusion and relevance

Our review demonstrates that PC levels were significantly higher in sepsis survivors compared to non-survivors and patients with sepsis but not disseminated intravascular coagulation (DIC). Our evaluation is limited by high RoB in included studies and poor reporting of the sensitivity and specificity of PC as a sepsis biomarker. Future studies are needed to determine the sensitivity and specificity of PC to identify its clinical significance as a biomarker for early sepsis recognition.

Trial Registration PROSPERO registration number: CRD42021229786. The study protocol was published in BMJ Open.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-03889-2.

Monitoring coagulation-fibrinolysis activation prompted timely diagnosis of hemophagocytic lymphohistiocytosis-related disseminated intravascular coagulation

Background

Timely diagnosis of disseminated intravascular coagulation (DIC) in hemophagocytic lymphohistiocytosis (HLH) patients is crucial but challenging, as HLH interferes with the results of the laboratory tests included in the DIC score system.

Case presentation

Here, we reported a case of lymphoma-associated HLH, in which coagulation-fibrinolysis activation /inhibition markers (TAT, tPAIC, and PIC), prompted timely diagnosis of early stage DIC (initial phase of microvascular thrombosis, yet non-overt), prior to the development of organ failures and/or bleedings.

Conclusions

This report highlights the importance of the implementation of new biomarkers (such as TAT, tPAIC, and PIC), into the diagnostic work-up for coagulation disorders. These biomarkers are directly suggestive of microthrombus formation, therefore they can be of paramount importance in diagnosing DIC with complicated etiologies, such as hematological diseases-related DIC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12959-021-00338-y.

HSF1 Alleviates Microthrombosis and Multiple Organ Dysfunction in Mice with Sepsis by Upregulating the Transcription of Tissue-Type Plasminogen Activator

Sepsis is a life-threatening complication of infection closely associated with coagulation abnormalities. Heat shock factor 1 (HSF1) is an important transcription factor involved in many biological processes, but its regulatory role in blood coagulation remained unclear. We generated a sepsis model in HSF1-knockout mice to evaluate the role of HSF1 in microthrombosis and multiple organ dysfunction. Compared with septic wild-type mice, septic HSF1-knockout mice exhibited a greater degree of lung, liver, and kidney tissue damage, increased fibrin/: fibrinogen deposition in the lungs and kidneys, and increased coagulation activity. RNA-seq analysis revealed that tissue-type plasminogen activator (t-PA) was upregulated in the lung tissues of septic mice, and the level of t-PA was significantly lower in HSF1-knockout mice than in wild-type mice in sepsis. The effects of HSF1 on t-PA expression were further validated in HSF1-knockout mice with sepsis and in vitro in mouse brain microvascular endothelial cells using HSF1 RNA interference or overexpression under lipopolysaccharide stimulation. Bioinformatics analysis, combined with electromobility shift and luciferase reporter assays, indicated that HSF1 directly upregulated t-PA at the transcriptional level. Our results reveal, for the first time, that HSF1 suppresses coagulation activity and microthrombosis by directly upregulating t-PA, thereby exerting protective effects against multiple organ dysfunction in sepsis.

Delayed Administration of Antibiotics Beyond the First Hour of Recognition Is Associated with Increased Mortality Rates in Children with Sepsis/Severe Sepsis and Septic Shock

OBJECTIVE

To compare the risk of mortality and other clinical outcomes in children with sepsis, severe sepsis, or septic shock who received antibiotics within the first hour of recognition (early antibiotics group) with those who received antibiotics after the first hour (delayed antibiotics group).

STUDY DESIGN

In this prospective cohort study, we enrolled children <17 years of age presenting to the pediatric emergency and diagnosed with sepsis or septic shock without prior antibiotic therapy. Primary outcome was mortality and the secondary outcomes were day 1 Pediatric Logistic Organ Dysfunction score, ventilator-free days, and hospital-free days. These outcomes were compared between the early and the delayed antibiotic groups. The reference point for defining early and delayed antibiotic groups was time 0, which was measured from the time the patient was diagnosed to have sepsis, severe sepsis, or septic shock to the time of administration of the first dose of antibiotics.

RESULTS

About three-fourths (77%) of the 441 children enrolled had septic shock. A total of 241 (55%) and 200 (45%) children were in the delayed and early antibiotic groups, respectively. Children in the delayed group had significantly higher odds of mortality than those in the early group (29% vs 20%; aOR 1.83; 95% CI, 1.14-2.92; P = .01). The time to shock reversal was significantly shorter, and the ventilator-free days and hospital-free days were significantly greater, in the early antibiotic group. There was no difference between the groups with regard to any of the other clinical outcomes.

CONCLUSIONS

Delayed administration of antibiotics beyond 1 hour of recognition was associated with higher mortality rates in children with sepsis, severe sepsis, and septic shock. Antibiotics should be administered within the first hour, along with other resuscitative measures, in these children.

Adipose-Derived Inflammatory and Coagulant Mediators in Patients With Sepsis

ABSTRACT

Results from preclinical sepsis studies using rodents are often criticized as not being reproducible in humans. Using a murine model, we previously reported that visceral adipose tissues (VAT) are highly active during the acute inflammatory response, serving as a major source of inflammatory and coagulant mediators. The purpose of this study was to determine whether these findings are recapitulated in patients with sepsis and to evaluate their clinical significance. VAT and plasma were obtained from patients undergoing intra-abdominal operations with noninflammatory conditions (control), local inflammation, or sepsis. In mesenteric and epiploic VAT, gene expression of pro-inflammatory (TNFα, IL-6, IL-1α, IL-1β) and pro-coagulant (PAI-1, PAI-2, TSP-1, TF) mediators was increased in sepsis compared with control and local inflammation groups. In the omentum, increased expression was limited to IL-1β, PAI-1, and PAI-2, showing a depot-specific regulation. Histological analyses showed little correlation between cellular infiltration and gene expression, indicating a resident source of these mediators. Notably, a strong correlation between PAI-1 expression in VAT and circulating protein levels was observed, both being positively associated with markers of acute kidney injury (AKI). In another cohort of septic patients stratified by incidence of AKI, circulating PAI-1 levels were higher in those with versus without AKI, thus extending these findings beyond intra-abdominal cases. This study is the first to translate upregulation of VAT mediators in sepsis from mouse to human. Collectively, the data suggest that development of AKI in septic patients is associated with high plasma levels of PAI-1, likely derived from resident cells within VAT.

Fibrinolytic Alterations in Sepsis: Biomarkers and Future Treatment Targets

Sepsis is a life-threatening condition which develops as a dysregulated immune response in the face of infection and which is associated with profound hemostatic disturbances and in the most extreme cases disseminated intravascular coagulation (DIC). In addition, the fibrinolytic system is subject to alterations during infection and sepsis, and impaired fibrinolysis is currently considered a key player in sepsis-related microthrombus formation and DIC. However, we still lack reliable biomarkers to assess fibrinolysis in the clinical setting. Furthermore, drugs targeting the fibrinolytic system have potential value in sepsis patients with severe fibrinolytic disturbances, but these are still being tested in the preclinical stage. The present review provides an overview of key fibrinolytic changes in sepsis, reviews the current literature on potential laboratory markers of altered fibrinolysis in adult sepsis patients, and discusses future perspectives for diagnosis and treatment of fibrinolytic disturbances in sepsis patients.

Characterization of circulating thrombin in patients with septic shock: a prospective observational study

Septic shock is characterized by a dysregulated response to infection, hypotension and activation of the coagulation system. Markers of coagulation activation are commonly used to diagnose and monitor ensuing coagulopathies. In this study, we sought to determine levels of circulating thrombin in patients with septic shock. To characterize levels of circulating, active thrombin in patients with septic shock. 48 patients with septic shock were included in this prospective, observational study. Blood samples were obtained on admission, day 1, day 3 and day 6. Levels of active thrombin were measured using a standardized, clinically applicable oligonucleotide (aptamer)-based enzyme-capture assay (OECA). Thrombin levels were correlated with established indirect thrombin parameters, conventional coagulation tests, laboratory parameters, patient characteristics and outcome. Elevated levels of thrombin were detected in 27 patients (56.3%) during the course of the study. Thrombin levels were positively correlated with thrombin-antithrombin complexes (r = 0.30, p < 0.05) and negatively associated with FVII levels (r = - 0.28, p < 0.05). Thrombin levels on admission did not predict 30-day mortality (OR 0.82, 95% CI 0.23-2.92, p = 0.77). Circulating levels of active thrombin can be measured in a subset of patients with septic shock. Although thrombin levels are correlated with established markers of coagulation, they do not provide additional prognostic information.

Evaluation of analytic and clinical performance of thrombin-antithrombin complex and D-dimer assay in prognosis of acute ischemic stroke

: To evaluate analytic and clinical performance of plasma thrombin-antithrombin complex (TAT) and D-dimer assay in assessing the severity and outcome of acute ischemic stroke. The prospective study was conducted and extended from January 2018 to December 2018. A total of 236 patients admitted within 24 h after neurologic symptoms onset were recruited. The median TAT and D-dimer levels were significantly higher in the acute ischemic stroke patients than in the controls. The average TAT levels in patients with mild, moderately severe and severe stroke were 1.75 [interquartile ranges (IQR), 1.1-2.6], 3.3 (IQR, 1.8-4.5) and 13.5 (IQR, 7.2-15.3) ng/ml. The D-dimer levels of respective patient groups were 0.39 (IQR, 0.22-0.73), 0.58 (IQR, 0.39-1.25) and 3.59 (IQR, 1.73-4.74) mg/l. With the optimal cut-off TAT level (1.75 ng/ml) determined from receiver operating characteristic analysis, the Area under the curve (AUC), the sensitivity and specificity of TAT for stroke diagnosis were 0.763, 58.1 and 87.8%. The cut-off D-dimer level was 0.38 mg/l and the AUC, the sensitivity and specificity were 0.772, 60.2 and 88.9%. The Area under the receiver operating characteristic curves (AUROCs) and sensitivity in the moderate to severe stroke increased to 0.903 and 86.9% for TAT, and 0.880 and 80.3% for D-dimer, respectively. Age and high TAT level were significant independent risk factors for stroke severity. Age, high initial National Institutes of Health Stroke Scale score and high TAT level were significant independent poor prognostic factors on multivariate analysis. TAT and D-dimer were superior in separating the moderate-to-severe stroke than mild stroke. A high TAT plasma level is an independent predictor for stroke severity and poor prognosis during 1-month follow-up.

Incidence and risk factors of venous thromboembolism after percutaneous nephrolithotomy: a single-center experience

PURPOSE

To determine the incidence and risk factors of the venous thromboembolism (VTE) in patients undergoing percutaneous nephrolithotomy (PCNL).

METHODS

We retrospectively reviewed the records of 896 consecutive cases receiving PCNL between July 2018 and August 2020 in our institution. Univariate analysis was performed to identify the risk factors of VTE, and multivariate logistic regression analysis was further performed to determine the independent risk factors. Furthermore, the corresponding nomogram was conducted to establish a predicted model for VTE.

RESULTS

The overall incidence of VTE was 2.8%. The multivariate logistic regression analysis showed that discontinued anticoagulant or antiplatelet therapies (OR 4.505, 95% CI 1.410-14.401), increased postoperative 12-h D-dimer (OR 11.162, 95% CI 2.370-52.574), hydronephrosis (OR 3.303, 95% CI 1.303-8.375), higher Caprini risk assessment model (RAM) score (OR 3.233, 95% CI 1.207-8.659) and postoperative sepsis or septic shock (OR 3.784, 95% CI 1.163-12.306) were independent risk factors of VTE following PCNL. Moreover, the area under the curve of postoperative 12-h D-dimer, hydronephrosis and Caprini RAM score was 0.826, 0.621 and 0.660, respectively. Based on the identified independent risk factors, the well-calibrated nomogram showed a moderate discriminative ability with concordance index 0.731.

CONCLUSIONS

2.8% of patients developed VTE following PCNL. Regarding those patients who have independent risk factors in this study, due attention should be paid to the effective thromboprophylaxis and the early detection of VTE.

Therapeutic strategies in patients with coagulopathy and disseminated intravascular coagulation: awareness of the phase-dependent characteristics

INTRODUCTION

Disseminated intravascular coagulation (DIC) has long been understood as a condition where both thrombotic and hemostatic abnormalities coexist. DIC is a difficult complication for clinicians to manage as it is due to multiple underlying complications of pathophysiologic abnormalities in diverse disease states. Ongoing research continues to define the meaning of DIC, evaluate therapeutic options, and how it presents with the complex paradigm of systemic activation of coagulation. In this review we introduce the current topis regarding this tough situation.

EVIDENCE ACQUISITION

Online search of published medical literature through MEDLINE and Web of Sience using the term "disseminated intravascular coagulation", "coagulopathy", "coagulation disorder", "hemostasis", "fibrinolysis", "thrombus" and "anticoagulants".

EVIDENCE SYNTHESIS

Articles were chosen for inclusion based on their relevance to disseminated intravascular coagulation, coagulopathy, hemostasis and thrombosis in sepsis, COVID-19, trauma, and obstetrics. Reference lists were reviewed to identify additional relevant articles.

CONCLUSIONS

DIC is recognized as a pathologically triggered and dysregulated systemic activation of coagulation in response to various noxious stimuli. DIC's phenotype and clinical manifestations can vary from prothrombotic to hemorrhagic, depending on the underlying diseases. However, the fundamental mechanisms of systemic and vascular endothelial dysfunction can be explained as different phases of the acute response, with an initial prothrombotic phase that can commonly change to hemostatic insufficiency. Thrombin is the key initiator of the pathophysiologic process along with endothelial injury and initially fibrinolysis activation followed by fibrinolysis suppression. There is no established approach for managing DIC beyond initially treating the underlying disease and replacement therapy for the management of coagulopathy. Targeting anticoagulation therapy with antithrombin concentrates and recombinant thrombomodulin for the prevention of microthrombus formation, and antifibrinolytic therapy using tranexamic acid for the coagulopathy after massive bleeding, continue to be studied as therapeutic options.

Endotheliopathy in septic conditions: mechanistic insight into intravascular coagulation

Endothelial cells play a key role in maintaining intravascular patency through their anticoagulant properties. They provide a favorable environment for plasma anticoagulant proteins, including antithrombin, tissue factor pathway inhibitor, and protein C. Under septic conditions, however, the anticoagulant properties of endothelial cells are compromised. Rather, activated/injured endothelial cells can provide a scaffold for intravascular coagulation. For example, the expression of tissue factor, an important initiator of the coagulation pathway, is induced on the surface of activated endothelial cells. Phosphatidylserine, a high-affinity scaffold for gamma-carboxyglutamate domain containing coagulation factors, including FII, FVII, FIX, and FX, is externalized to the outer leaflet of the plasma membrane of injured endothelial cells. Hemodilution decreases not only coagulation factors but also plasma anticoagulant proteins, resulting in unleashed activation of coagulation on the surface of activated/injured endothelial cells. The aberrant activation of coagulation can be suppressed in part by the supplementation of recombinant antithrombin and recombinant thrombomodulin. This review aims to overview the physiological and pathological functions of endothelial cells along with proof-of-concept in vitro studies. The pathophysiology of COVID-19-associated thrombosis is also discussed.

Disseminated intravascular coagulation: epidemiology, biomarkers, and management

Disseminated intravascular coagulation (DIC) is a systemic activation of the coagulation system, which results in microvascular thrombosis and, simultaneously, potentially life-threatening haemorrhage attributed to consumption of platelets and coagulation factors. Underlying conditions, e.g. infection, cancer, or obstetrical complications are responsible for the initiation and propagation of the DIC process. This review provides insights into the epidemiology of DIC and the current understanding of its pathophysiology. It details the use of diagnostic biomarkers, current diagnostic recommendations from international medical societies, and it provides an overview of emerging diagnostic and prognostic biomarkers. Last, it provides guidance on management. It is concluded that timely and accurate diagnosis of DIC and its underlying condition is essential for the prognosis. Treatment should primarily focus on the underlying cause of DIC and supportive treatment should be individualised according to the underlying aetiology, patient's symptoms and laboratory records.

Heparin prevents caspase-11-dependent septic lethality independent of anticoagulant properties

Heparin, a mammalian polysaccharide, is a widely used anticoagulant medicine to treat thrombotic disorders. It is also known to improve outcomes in sepsis, a leading cause of mortality resulted from infection-induced immune dysfunction. Whereas it is relatively clear how heparin exerts its anticoagulant effect, the immunomodulatory mechanisms enabled by heparin remain enigmatic. Here, we show that heparin prevented caspase-11-dependent immune responses and lethality in sepsis independent of its anticoagulant properties. Heparin or a chemically modified form of heparin without anticoagulant function inhibited the alarmin HMGB1-lipopolysaccharide (LPS) interaction and prevented the macrophage glycocalyx degradation by heparanase. These events blocked the cytosolic delivery of LPS in macrophages and the activation of caspase-11, a cytosolic LPS receptor that mediates lethality in sepsis. Survival was higher in septic patients treated with heparin than those without heparin treatment. The identification of this previously unrecognized heparin function establishes a link between innate immune responses and coagulation.

HSF1 Alleviates Microthrombosis and Multiple Organ Dysfunction in Mice with Sepsis by Upregulating the Transcription of Tissue-Type Plasminogen Activator

Sepsis is a life-threatening complication of infection closely associated with coagulation abnormalities. Heat shock factor 1 (HSF1) is an important transcription factor involved in many biological processes, but its regulatory role in blood coagulation remained unclear. We generated a sepsis model in HSF1-knockout mice to evaluate the role of HSF1 in microthrombosis and multiple organ dysfunction. Compared with septic wild-type mice, septic HSF1-knockout mice exhibited a greater degree of lung, liver, and kidney tissue damage, increased fibrin/: fibrinogen deposition in the lungs and kidneys, and increased coagulation activity. RNA-seq analysis revealed that tissue-type plasminogen activator (t-PA) was upregulated in the lung tissues of septic mice, and the level of t-PA was significantly lower in HSF1-knockout mice than in wild-type mice in sepsis. The effects of HSF1 on t-PA expression were further validated in HSF1-knockout mice with sepsis and in vitro in mouse brain microvascular endothelial cells using HSF1 RNA interference or overexpression under lipopolysaccharide stimulation. Bioinformatics analysis, combined with electromobility shift and luciferase reporter assays, indicated that HSF1 directly upregulated t-PA at the transcriptional level. Our results reveal, for the first time, that HSF1 suppresses coagulation activity and microthrombosis by directly upregulating t-PA, thereby exerting protective effects against multiple organ dysfunction in sepsis.

Recent advances in the research and management of sepsis-associated DIC

Disseminated intravascular coagulation (DIC) is a common and life-threatening complication in sepsis. Sepsis-associated DIC is recognized as the systemic activation in coagulation with suppressed fibrinolysis that leads to organ dysfunction in combination with systemic intravascular inflammation. In this process, thrombin contributes a key role in connecting both coagulation and inflammation. Endothelial injury, a result of sepsis, causes DIC due to the effect of multiple activated factors that include neutrophils, platelets, and damage-associated molecular patterns. Recent advances in the understanding of pathophysiology have made it possible to diagnose sepsis-associated DIC at earlier timing with better accuracy. However, progress in the treatment is still limited, and new therapeutics for sepsis-associated DIC are needed.

Validating plasminogen activator inhibitor-1 as a poor prognostic factor in sepsis

Aim

Our previous report indicated that plasminogen activator inhibitor‐1 (PAI‐1) levels of ≥83 ng/mL in patients with sepsis tended to be associated with disseminated intravascular coagulation (DIC), suppressed fibrinolysis, multiple organ dysfunction, and mortality. Therefore, the present study aimed to validate whether 83 ng/mL was a useful cut‐off value for using PAI‐1 levels to predict a poor prognosis in sepsis.

Methods

Patients with sepsis were included in this single‐center retrospective study. The patients were classified as having high or low PAI‐1 values (<83 ng/mL versus ≥83 ng/mL), and were compared in terms of their pre‐DIC state, intensive care unit‐free days, continuous renal replacement therapy‐free days, ventilator‐free days, catecholamine‐free days, and 28‐day survival rate.

Results

The high PAI‐1 group included 61 patients (54%) and the low PAI‐1 group included 52 patients (46%). The high PAI‐1 group had significantly higher frequencies of a pre‐DIC state within 1 week (P = 0.009). There was no significant difference in ventilator‐free days. However, the high PAI‐1 group had significantly lower values for intensive care unit‐free days (P = 0.01), continuous renal replacement therapy‐free days (P = 0.02), and catecholamine‐free days (P = 0.02). The high PAI‐1 group also had a significantly lower 28‐day survival rate based on the Kaplan–Meier analysis (log–rank, P = 0.03).

Conclusion

Patients with sepsis and PAI‐1 levels of ≥83 ng/mL had elevated risks of coagulopathy, organ failure, and mortality. Thus, these results suggest that 83 ng/mL could be a useful cut‐off value for prognostication based on PAI‐1 levels in this setting.

Acute Ischemic Stroke in COVID-19: Putative Mechanisms, Clinical Characteristics, and Management

The emergence and spread of the highly contagious novel coronavirus disease (COVID-19) have triggered the greatest public health challenge of the last century. Aside from being a primary respiratory disease, acute ischemic stroke has emerged as a complication of the disease. While current evidence shows COVID-19 could cause ischemic stroke especially in severe disease, there are similarities in the risk factors for severe COVID-19 as well as ischemic stroke, underscoring the complex relationship between these two conditions. The pandemic has created challenges for acute stroke care. Rapid assessment and time-sensitive interventions required for optimum outcomes in acute stroke care have been complicated by COVID-19 due to the need for disease transmission preventive measures. The purpose of this article is to explore the putative mechanisms of ischemic stroke in COVID-19 and the clinical characteristics of COVID-19 patients who develop ischemic stroke. In addition, we discuss the challenges of managing acute ischemic stroke in the setting of COVID-19 and review current management guidelines. We also highlighted potential areas for future research.

The role of type 1 interferons in coagulation induced by gram-negative bacteria

Bacterial infection not only stimulates innate immune responses but also activates coagulation cascades. Overactivation of the coagulation system in bacterial sepsis leads to disseminated intravascular coagulation (DIC), a life-threatening condition. However, the mechanisms by which bacterial infection activates the coagulation cascade are not fully understood. Here we show that type 1 interferons (IFNs), a widely expressed family of cytokines that orchestrate innate antiviral and antibacterial immunity, mediate bacterial infection-induced DIC by amplifying the release of high-mobility group box 1 (HMGB1) into the bloodstream. Inhibition of the expression of type 1 IFNs and disruption of their receptor IFN-α/βR or downstream effector (eg, HMGB1) uniformly decreased gram-negative bacteria-induced DIC. Mechanistically, extracellular HMGB1 markedly increased the procoagulant activity of tissue factor by promoting the externalization of phosphatidylserine to the outer cell surface, where phosphatidylserine assembles a complex of cofactor-proteases of the coagulation cascades. These findings not only provide novel insights into the link between innate immune responses and coagulation, but they also open a new avenue for developing novel therapeutic strategies to prevent DIC in sepsis.

Enigmatic role of coagulopathy among sepsis survivors: a review of coagulation abnormalities and their possible link to chronic critical illness

There are sparse clinical data addressing the persistence of disordered coagulation in sepsis and its role in chronic critical illness. Coagulopathy in the absence of anticoagulant therapy and/or liver disease can be highly variable in sepsis, but it tends to be prolonged in patients in the intensive care unit with a length of stay greater than 14 days. These coagulation abnormalities tend to precede multisystem organ failure and persistence of these coagulation derangements can predict 28-day mortality. The studies evaluated in this review consistently link sepsis-associated coagulopathy to poor long-term outcomes and indicate that disordered coagulation is associated with unfavorable outcomes in chronic critical illness. However, the causative mechanism and the definitive link remain unclear. Longer follow-up and more granular data will be required to fully understand coagulopathy in the context of chronic critical illness.

Bacterial outer membrane vesicles induce disseminated intravascular coagulation through the caspase-11-gasdermin D pathway

BACKGROUND

Disseminated intravascular coagulation (DIC), a severe complication of sepsis, promotes multiple organ dysfunctions and lethality. Bacterial infection is the most common cause of sepsis. We previously show an important role of bacteria-released outer membrane vesicles (OMVs) in bacterial infection-induced DIC. In the light of recent advance that activation of caspase-11 and its enzymatic substrate gasdermin D (GSDMD) is able to trigger coagulation, we postulate that OMVs might induce DIC through the caspase-11-GSDMD pathway.

METHODS

Caspase-11- or GSDMD-deficient mice and their wild-type (WT) controls were injected with purified Escherichia coli-derived OMVs. Blood samples were then collected. The development of DIC was assessed in terms of the occurrence of coagulopathy, the organ injuries and the lethality. Peritoneal macrophages derived from WT, Caspase-11- or GSDMD-deficient mice were stimulated with OMVs. Then the cell surface tissue factor (TF) activity and thrombin generation were assessed.

RESULTS

Genetic deletion of Caspase-11 or GSDMD or pharmacological inhibition of caspase-11 markedly attenuated OMVs-induced coagulopathy, multiple organ injuries and mortality. Caspase-11- or GSDMD-deficient macrophages exhibited markedly reduced TF activity after OMVs stimulation.

CONCLUSION

OMVs induce DIC through the caspase-11-GSDMD pathway. These findings might open a new avenue to prevent or treat bacterial infection-induced DIC.

Phospho-Tyr705 of STAT3 is a therapeutic target for sepsis through regulating inflammation and coagulation

BACKGROUND

Sepsis is an infection-induced aggressive and life-threatening organ dysfunction with high morbidity and mortality worldwide. Infection-associated inflammation and coagulation promote the progression of adverse outcomes in sepsis. Here, we report that phospho-Tyr705 of STAT3 (pY-STAT3), not total STAT3, contributes to systemic inflammation and coagulopathy in sepsis.

METHODS

Cecal ligation and puncture (CLP)-induced septic mice were treated with BP-1-102, Napabucasin, or vehicle control respectively and then assessed for systemic inflammation, coagulation response, lung function and survival. Human pulmonary microvascular endothelial cells (HPMECs) and Raw264.7 cells were exposed to lipopolysaccharide (LPS) with pharmacological or genetic inhibition of pY-STAT3. Cells were assessed for inflammatory and coagulant factor expression, cell function and signaling.

RESULTS

Pharmacological inhibition of pY-STAT3 expression by BP-1-102 reduced the proinflammatory factors, suppressed coagulation activation, attenuated lung injury, alleviated vascular leakage and improved the survival rate in septic mice. Pharmacological or genetic inhibition of pY-STAT3 diminished LPS-induced cytokine production in macrophages and protected pulmonary endothelial cells via the IL-6/JAK2/STAT3, NF-κB and MAPK signaling pathways. Moreover, the increase in procoagulant indicators induced by sepsis such as tissue factor (TF), the thrombin-antithrombin complex (TAT) and D-Dimer were down-regulated by pY-STAT3 inhibition.

CONCLUSIONS

Our results revealed a therapeutic role of pY-STAT3 in modulating the inflammatory response and defective coagulation during sepsis. Video Abstract.

Biomarkers of sepsis: time for a reappraisal

INTRODUCTION

Sepsis biomarkers can have important diagnostic, therapeutic, and prognostic functions. In a previous review, we identified 3370 references reporting on 178 different biomarkers related to sepsis. In the present review, we evaluate the progress in the research of sepsis biomarkers.

METHODS

Using the same methodology as in our previous review, we searched the PubMed database from 2009 until September 2019 using the terms "Biomarker" AND "Sepsis." There were no restrictions by age or language, and all studies, clinical and experimental, were included.

RESULTS

We retrieved a total of 5367 new references since our previous review. We identified 258 biomarkers, 80 of which were new compared to our previous list. The majority of biomarkers have been evaluated in fewer than 5 studies, with 81 (31%) being assessed in just a single study. Apart from studies of C-reactive protein (CRP) or procalcitonin (PCT), only 26 biomarkers have been assessed in clinical studies with more than 300 participants. Forty biomarkers have been compared to PCT and/or CRP for their diagnostic value; 9 were shown to have a better diagnostic value for sepsis than either or both of these biomarkers. Forty-four biomarkers have been evaluated for a role in answering a specific clinical question rather than for their general diagnostic or prognostic properties in sepsis.

CONCLUSIONS

The number of biomarkers being identified is still increasing although at a slower rate than in the past. Most of the biomarkers have not been well-studied; in particular, the clinical role of these biomarkers needs to be better evaluated.

Clinical investigation of the utility of a pair of coagulation-fibrinolysis markers for definite diagnosis of sepsis-induced disseminated intravascular coagulation: A single-center, diagnostic, prospective, observational study

BACKGROUND

Disseminated intravascular coagulation (DIC) often occurs with sepsis. A scoring system has been used for the diagnosis of DIC, but the system included at least 4 parameters. The purpose of this study was to propose a simple set of DIC criteria with coagulation-fibrinolysis markers (CFMs).

METHODS

Patients with ≥2 signs of systemic inflammatory response syndrome and a quick Sequential Organ Failure Assessment score ≥ 2 points were investigated. All blood samples were collected on Days 0, 1, 3, and 7. Cutoff values of CFMs were calculated by receiver operating curve analysis. Positive predictive values (PPVs) and negative predictive values (NPVs) for the Japanese Association for Acute Medicine (JAAM) DIC criteria were evaluated by pairing the markers. Differences were analyzed by the Mann-Whitney U test, Kruskal-Wallis test, and the log-rank test.

RESULTS

A total of 107 patients were enrolled. The cutoff values of soluble fibrin (SF), protein C (PC), and plasminogen activator inhibitor (PAI)-1 were 48 μg/mL, 42%, and 71 ng/mL according to the International Society of Thrombosis and Hemostasis DIC criteria. The PPV of the severe SFxPC group was 100% for the JAAM DIC criteria, excluding Day 0.

CONCLUSION

Cutoff values of SF over 48 μg/mL and PC <42% could almost definitely identify JAAM DIC.

Fc-modified HIT-like monoclonal antibody as a novel treatment for sepsis

Sepsis is characterized by multiorgan system dysfunction that occurs because of infection. It is associated with high morbidity and mortality and is in need of improved therapeutic interventions. Neutrophils play a crucial role in sepsis, releasing neutrophil extracellular traps (NETs) composed of DNA complexed with histones and toxic antimicrobial proteins that ensnare pathogens, but also damage host tissues. At presentation, patients often have a significant NET burden contributing to the multiorgan damage. Therefore, interventions that inhibit NET release would likely be ineffective at preventing NET-based injury. Treatments that enhance NET degradation may liberate captured bacteria and toxic NET degradation products (NDPs) and likely be of limited therapeutic benefit as well. We propose that interventions that stabilize NETs and sequester NDPs may be protective in sepsis. We showed that platelet factor 4 (PF4), a platelet-associated chemokine, binds and compacts NETs, increasing their resistance to DNase I. We now show that PF4 increases NET-mediated bacterial capture, reduces the release of NDPs, and improves outcome in murine models of sepsis. A monoclonal antibody KKO which binds to PF4-NET complexes, further enhances DNase resistance. However, the Fc portion of this antibody activates the immune response and increases thrombotic risk, negating any protective effects in sepsis. Therefore, we developed an Fc-modified KKO that does not induce these negative outcomes. Treatment with this antibody augmented the effects of PF4, decreasing NDP release and bacterial dissemination and increasing survival in murine sepsis models, supporting a novel NET-targeting approach to improve outcomes in sepsis.

Severe Antithrombin Deficiency May be Associated With a High Risk of Pathological Progression of DIC With Suppressed Fibrinolysis

The frequency of severe antithrombin deficiency (SAD) was examined in the hematopoietic disorder-, infectious-, and basic-types of the disseminated intravascular coagulation (DIC). A posthoc analysis of 3008 DIC patients (infectious-type, 1794; hematological disorder-type, 813; and basic-type, 401) from post-marketing surveillance data of thrombomodulin alfa was performed. The clinical features of patients and outcomes were compared between patients with and without SAD, using an antithrombin cutoff value of 50%. Patients with SAD accounted for 40.4% of infectious-type DIC, 8.0% of hematopoietic disorder-type DIC, and 26.7% of basic-type DIC. There was no significant difference in thrombin-antithrombin complex levels between patients with and without SAD. The decreased fibrinogen level and differences in clinical features were significantly greater but the increases in fibrinolytic markers were significantly lower in patients with SAD than in those without. The 28-day survival rate was significantly lower in patients with SAD than in those without. Severe antithrombin deficiency was observed in all types of DIC, including hematopoietic disorders. Both hypofibrinolysis and hypercoagulability in patients with SAD may cause multiple organ failure and poor outcomes.

Diagnostic and Prognostic Value of TAT, PIC, TM, and t-PAIC in Malignant Tumor Patients With Venous Thrombosis

BACKGROUND

Venous thromboembolism (VTE) is an important complication in patients with malignant tumors. Its exact diagnosis and treatment are still lacking. We used a high-sensitive chemiluminescence method to detect thrombin-antithrombin III complex (TAT), plasmin-α2-plasmininhibitor complex (PIC), thrombomodulin (TM), and tissue plasminogen activator-inhibitor complex(t-PAIC) in combination with D-dimer and fibrin degradation product (FDP) to analyze their diagnostic and prognostic value in patients with malignant tumors.

METHODS

In total, 870 patients with confirmed malignant tumors were included, 82 of whom had diagnosed VTE; 200 healthy individuals were classified as the control group. The TAT, PIC, TM, and t-PAIC were detected using Sysmex HISCL5000 automated analyzers, whereas FDP and D-dimer were detected using Sysmex CS5100 coagulation analyzer. Receiver operating characteristic (ROC) curves were used to evaluate the diagnostic efficiency. Survival probabilities were determined using Kaplan-Meier analysis, and multivariate analyses were performed using a Cox regression model.

RESULTS

Compared with healthy controls, patients with malignant tumors showed significantly elevated TAT, PIC, TM, t-PAIC, D-dimer, and FDP. Similarly, compared with patients in the non-thrombosis group, those in the thrombosis group showed significantly elevated levels of the above mentioned markers. Logistic regression analysis showed that TAT, PIC, TM, t-PAIC, D-Dimer, and FDP were all associated with VTE. ROC analysis showed that "TAT+PIC+TM+t-PAIC+D-dimer+FDP"showed the highest sensitivity and specificity. Patients with elevated TAT, PIC, TM, and t-PAIC had a significantly shorter survival. Multivariate Cox survival analysis showed that TM and t-PAIC were significantly associated with poor prognosis. In addition, the incidence of VTE was significantly lower in patients with malignant tumors who were treated with low-molecular-weight heparin (LMWH), and their survival period was significantly longer than that of patients with malignant tumors who were not treated with LMWH.

CONCLUSION

TAT, PIC, TM, and t-PAIC combined with D-dimer and FDP were better than the application of a single marker in the diagnosis of VTE in patients with malignant tumors. TAT and PIC can be used as sensitive markers in the diagnosis of VTE but not as prognostic markers. TM and t-PAIC might be independent prognostic indicators in patients with malignant tumors, regardless of the state of thrombus.

Bacterial Endotoxin Activates the Coagulation Cascade through Gasdermin D-Dependent Phosphatidylserine Exposure

Excessive activation of the coagulation system leads to life-threatening disseminated intravascular coagulation (DIC). Here, we examined the mechanisms underlying the activation of coagulation by lipopolysaccharide (LPS), the major cell-wall component of Gram-negative bacteria. We found that caspase-11, a cytosolic LPS receptor, activated the coagulation cascade. Caspase-11 enhanced the activation of tissue factor (TF), an initiator of coagulation, through triggering the formation of gasdermin D (GSDMD) pores and subsequent phosphatidylserine exposure, in a manner independent of cell death. GSDMD pores mediated calcium influx, which induced phosphatidylserine exposure through transmembrane protein 16F, a calcium-dependent phospholipid scramblase. Deletion of Casp11, ablation of Gsdmd, or neutralization of phosphatidylserine or TF prevented LPS-induced DIC. In septic patients, plasma concentrations of interleukin (IL)-1α and IL-1β, biomarkers of GSDMD activation, correlated with phosphatidylserine exposure in peripheral leukocytes and DIC scores. Our findings mechanistically link immune recognition of LPS to coagulation, with implications for the treatment of DIC.