Effect of a Recombinant Human Soluble Thrombomodulin on Baseline Coagulation Biomarker Levels and Mortality Outcome in Patients With Sepsis-Associated Coagulopathy

Understanding, assessing and treating immune, endothelial and haemostasis dysfunctions in bacterial sepsis

The interplay between the immune system, coagulation, and endothelium is critical in regulating the host response to infection. However, in sepsis and other critical illnesses, a dysregulated immune response can lead to excessive alterations in these mechanisms, resulting in coagulopathy, endothelial dysfunction, and multi-organ dysfunction. This review aims to provide a comprehensive analysis of the pathophysiological mechanisms that govern the complex interplay between immune dysfunction, endothelial dysfunction, and coagulation in sepsis. It emphasises clinical significance, evaluation methods, and potential therapeutic interventions. Understanding these mechanisms is essential for developing effective treatments that can modulate the immune response, mitigate thrombosis, restore endothelial function, and ultimately improve patient survival.

Novel nomogram for the prediction of sepsis-induced coagulopathy in the PICU: A multicentre retrospective study

INTRODUCTION

Sepsis-induced coagulopathy (SIC) is a severe complication of sepsis, characterized by poor prognosis and high mortality. However, the predictors of SIC in pediatric patients have yet to be identified. Our aim was to develop a user-friendly and efficient nomogram for predicting SIC in sepsis patients admitted to the pediatric intensive care unit (PICU).

MATERIALS AND METHODS

We screened 948 sepsis patients admitted to the PICU in three hospitals located in Shandong, China. Least absolute shrinkage and selector operation (LASSO) regression was used in the training cohort for variable selection and regularization. The selected variables were utilized to construct a nomogram for predicting the risk of SIC among sepsis patients admitted to the PICU.

RESULTS

Overall, SIC was observed in 324 (40.3 %) patients. The morbidity of SIC in sepsis patients is associated with age, fibrinogen, prothrombin time, C-reactive protein, lactate and the pediatric sequential organ failure assessment score. We developed a nomogram for the early identification of SIC in the training cohort (area under the curve [AUC] 0.869, 95 % confidence interval [CI] 0.830-0.907, sensitivity 75.7 %, specificity 84.8 %) and validation cohorts (validation cohort 1: AUC 0.854, 95 % CI 0.805-0.903, sensitivity 72.0 %, specificity 86.9 %; validation cohort 2: AUC 0.853, 95 % CI 0.796-0.910, sensitivity 70.1 %, specificity 87.8 %). The calibration plots of the nomogram demonstrated a high level of concordance in the SIC probabilities between the observed and predicted values.

CONCLUSIONS

The novel nomogram showed excellent predictive performance for the morbidity of SIC among sepsis patients admitted to the PICU, potentially assisting healthcare professionals in early identification and intervention for SIC.

Towards personalized medicine: a scoping review of immunotherapy in sepsis

Despite significant progress in our understanding of the pathophysiology of sepsis and extensive clinical research, there are few proven therapies addressing the underlying immune dysregulation of this life-threatening condition. The aim of this scoping review is to describe the literature evaluating immunotherapy in adult patients with sepsis, emphasizing on methods providing a "personalized immunotherapy" approach, which was defined as the classification of patients into a distinct subgroup or subphenotype, in which a patient's immune profile is used to guide treatment. Subgroups are subsets of sepsis patients, based on any cut-off in a variable. Subphenotypes are subgroups that can be reliably discriminated from other subgroup based on data-driven assessments. Included studies were randomized controlled trials and cohort studies investigating immunomodulatory therapies in adults with sepsis. Studies were identified by searching PubMed, Embase, Cochrane CENTRAL and ClinicalTrials.gov, from the first paper available until January 29th, 2024. The search resulted in 15,853 studies. Title and abstract screening resulted in 1409 studies (9%), assessed for eligibility; 771 studies were included, of which 282 (37%) were observational and 489 (63%) interventional. Treatment groups included were treatments targeting the innate immune response, the complement system, coagulation and endothelial dysfunction, non-pharmalogical treatment, pleiotropic drugs, immunonutrition, concomitant treatments, Traditional Chinese Medicine, immunostimulatory cytokines and growth factors, intravenous immunoglobulins, mesenchymal stem cells and immune-checkpoint inhibitors. A personalized approach was incorporated in 70 studies (9%). Enrichment was applied using cut-offs in temperature, laboratory, biomarker or genetic variables. Trials often showed conflicting results, possibly due to the lack of patient stratification or the potential influence of severity and timing on immunomodulatory therapy results. When a personalized approach was applied, trends of clinical benefit for several interventions emerged, which hold promise for future clinical trials using personalized immunotherapy.

Efficacy and safety of heparin for sepsis-induced disseminated intravascular coagulation (HepSIC): study protocol for a multicenter randomized controlled trial

BACKGROUND

Disseminated intravascular coagulation (DIC) occurs in 30-50% of septic patients and contributes to high mortality in the intensive care unit (ICU). However, there are few proven interventions for coagulation disorder management in sepsis. Experimental and clinical data have demonstrated that sepsis could benefit from unfractionated heparin (UFH) treatment. To date, there are no large multicenter trials to determine the safety and efficacy of UFH in septic patients with suspected DIC.

METHODS

A multicenter, double-blinded, placebo-controlled randomized trial is designed to recruit 600 patients who met sepsis 3.0 criteria and suspected DIC. Participants will be randomized (1:1) to receive UFH or saline via continuous intravenous administration for 7 days within 6 h of enrolment. The primary outcome is ICU mortality. The secondary outcome includes 28-day all-cause mortality, the improvement of Sequential Organ Failure Assessment scores, and the incidence of major hemorrhage. Investigators, participants, and statisticians will be blinded to the allocation.

DISCUSSION

The HepSIC trial is to evaluate the efficacy and safety of UFH on sepsis-related DIC across different areas of China. The small dosage of UFH administration would offer a new potential approach for treating sepsis-related coagulation disorders.

ETHICS AND DISSEMINATION

Ethical approval was granted by all the ethics committees of 20 participant centers. Results will be disseminated via peer-reviewed publications and presented at conferences.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02654561. Registered on 13 January 2016.

Why anticoagulant studies on sepsis fail frequently --- start with SCARLET

The Sepsis Coagulopathy Asahi Recombinant LE Thrombomodulin (SCARLET) trial has many defects, and thus cannot be the terminator of recombinant thrombomodulin (rTM). On the contrary, it provides sufficient evidence for further research. Based on analysis focusing on the failure of SCARLET and several previous anticoagulant studies, it is most important for new studies to grasp the following two points: (1) The enrolled cases should have sufficient disease severity and a clear standard for disseminated intravascular coagulation; (2) Heparin should not be used in combination with the investigated drugs. Multiple post-hoc analyses show that no combination of heparin will not increase the risk of thromboembolism. In fact, the combination of heparin can mask the true efficacy of the investigated drug. Due to the complexity of sepsis treatment and the limitations of clinical studies, the results of all treatment studies should be repeatedly verified, rather than be determined at one stroke. Some research conclusions contrary to disease physiology, pharmacology and clinical practice may be deceptive, and should be cautious rather than be simply accepted. On the other hand, the dissenting voices in the "consensus" scene are often well discussed by the authors and should be highly valued.

Distinct host-response signatures in circulatory shock: a narrative review

Circulatory shock is defined syndromically as hypotension associated with tissue hypoperfusion and often subcategorized according to hemodynamic profile (e.g., distributive, cardiogenic, hypovolemic) and etiology (e.g., infection, myocardial infarction, trauma, among others). These shock subgroups are generally considered homogeneous entities in research and clinical practice. This current definition fails to consider the complex pathophysiology of shock and the influence of patient heterogeneity. Recent translational evidence highlights previously under-appreciated heterogeneity regarding the underlying pathways with distinct host-response patterns in circulatory shock syndromes. This heterogeneity may confound the interpretation of trial results as a given treatment may preferentially impact distinct subgroups. Re-analyzing results of major 'neutral' treatment trials from the perspective of biological mechanisms (i.e., host-response signatures) may reveal treatment effects in subgroups of patients that share treatable traits (i.e., specific biological signatures that portend a predictable response to a given treatment). In this review, we discuss the emerging literature suggesting the existence of distinct biomarker-based host-response patterns of circulatory shock syndrome independent of etiology or hemodynamic profile. We further review responses to newly prescribed treatments in the intensive care unit designed to personalize treatments (biomarker-driven or endotype-driven patient selection in support of future clinical trials).

Endothelial dysfunction and immunothrombosis in sepsis

Sepsis is a life-threatening clinical syndrome characterized by multiorgan dysfunction caused by a dysregulated or over-reactive host response to infection. During sepsis, the coagulation cascade is triggered by activated cells of the innate immune system, such as neutrophils and monocytes, resulting in clot formation mainly in the microcirculation, a process known as immunothrombosis. Although this process aims to protect the host through inhibition of the pathogen’s dissemination and survival, endothelial dysfunction and microthrombotic complications can rapidly lead to multiple organ dysfunction. The development of treatments targeting endothelial innate immune responses and immunothrombosis could be of great significance for reducing morbidity and mortality in patients with sepsis. Medications modifying cell-specific immune responses or inhibiting platelet–endothelial interaction or platelet activation have been proposed. Herein, we discuss the underlying mechanisms of organ-specific endothelial dysfunction and immunothrombosis in sepsis and its complications, while highlighting the recent advances in the development of new therapeutic approaches aiming at improving the short- or long-term prognosis in sepsis.

Sepsis-related coagulopathy treatment based on the disseminated intravascular coagulation diagnostic criteria: a post-hoc analysis of a prospective multicenter observational study

BACKGROUND

The development of disseminated intravascular coagulation (DIC) in patients with sepsis has been repeatedly confirmed as a factor associated with poor prognosis. Anticoagulant therapy has been expected to improve sepsis patient outcomes, whereas no randomized controlled trials have demonstrated the survival benefit of anticoagulant therapies in non-specific overall sepsis. Patient selection based on the component of "high disease severity" in addition to "sepsis with DIC" has recently proved important in identifying appropriate targets for anticoagulant therapy. The aims of this study were to characterize "severe" sepsis DIC patients and to identify the patient population benefiting from anticoagulant therapy.

METHODS

This retrospective sub-analysis of a prospective multicenter study included 1,178 adult patients with severe sepsis from 59 intensive care units in Japan from January 2016 to March 2017. We examined the association of patient outcomes, including organ dysfunction and in-hospital mortality, with the DIC score and prothrombin time-international normalized ratio (PT-INR), one of the components of the DIC score, using multivariable regression models including the cross-product term between these indicators. Multivariate Cox proportional hazard regression analysis with non-linear restricted cubic spline including a three-way interaction term (anticoagulant therapy × the DIC score × PT-INR) was also performed. Anticoagulant therapy was defined as the administration of antithrombin, recombinant human thrombomodulin, or their combination.

RESULTS

In total, we analyzed 1013 patients. The regression model showed that organ dysfunction and in-hospital mortality deteriorated with higher PT-INR values in the range of < 1.5 and that this trend was more pronounced with higher DIC scores. Three-way interaction analysis demonstrated that anticoagulant therapy was associated with better survival outcome in patients with a high DIC score and high PT-INR. Furthermore, we identified a DIC score ≥ 5 and PT-INR ≥ 1.5 as the clinical threshold for identification of optimal targets for anticoagulant therapy.

CONCLUSIONS

The combined use of the DIC score and PT-INR helps in selecting the optimal patient population for anticoagulant therapy in sepsis-induced DIC. The results obtained from this study will provide valuable information regarding the study design of randomized controlled trials examining the effects of anticoagulant therapy for sepsis.

TRIAL REGISTRATION

UMIN-CTR, UMIN000019742. Registered on November 16, 2015.

How to manage coagulopathies in critically ill patients

Coagulopathy is a severe and frequent complication in critically ill patients, for which the pathogenesis and presentation may be variable depending on the underlying disease. Based on the dominant clinical phenotype, the current review differentiates between hemorrhagic coagulopathies, characterized by a hypocoagulable and hyperfibrinolysis state, and thrombotic coagulopathies with a systemic prothrombotic and antifibrinolytic phenotype. We discuss the differences in pathogenesis and treatment of the common coagulopathies.

Sepsis-Associated DIC with Decreased Levels of Antithrombin and Fibrinogen is the Target for Combination Therapy with Thrombomodulin Alfa and Antithrombin

Background  Disseminated intravascular coagulation (DIC) is not a homogeneous condition, but rather includes heterogeneous conditions, and its pathophysiology and outcome vary considerably depending on the background. Although anticoagulant therapy is expected to be of benefit in the treatment of DIC, previous studies have suggested that the benefits are limited only to a specific subtype. Objects  The purpose of this study was to identify the group that would benefit from combination therapy using thrombomodulin/antithrombin. Methods  The data from 2,839 patients registered in the postmarketing surveillance of thrombomodulin were evaluated. The patients were divided into four groups depending on antithrombin and fibrinogen levels, and the additive effects of antithrombin on thrombomodulin were examined in the groups. Results  The DIC score, Sequential Organ Failure Assessment score, and mortality were significantly higher in the DIC group with low-antithrombin/low-fibrinogen than in the DIC groups without either low antithrombin or low fibrinogen. The survival curve was significantly higher in DIC patients with combination therapy than in patients treated with thrombomodulin monotherapy, but this effect was seen only in patients with infection-based DIC. Conclusion  DIC patients with low-antithrombin/low-fibrinogen risk poor outcomes, but they can be the target of combination therapy with antithrombin and thrombomodulin as long as the DIC is due to infection.

Age-dependent thrombin generation predicts 30-day mortality and symptomatic thromboembolism after multiple trauma

Trauma-induced coagulopathy (TIC) is a risk factor for death and is associated with deviations in thrombin generation. TIC prevalence and thrombin levels increase with age. We assayed in vivo and ex vivo thrombin generation in injured patients (n = 418) to specifically investigate how age impacts thrombin generation in trauma and to address the prognostic ability of thrombin generation. Biomarkers of thrombin generation were elevated in young (< 40 years) and older (≥ 40 years) trauma patients. In vivo thrombin generation was associated with Injury Severity Score (ISS) and this association was stronger in young than older patients. In vivo thrombin generation decreased faster after trauma in the young than the older patients. Across age groups, in vivo thrombin generation separated patients dying/surviving within 30 days at a level comparable to the ISS score (AUC 0.80 vs. 0.82, p > 0.76). In vivo and ex vivo thrombin generation also predicted development of thromboembolic events within the first 30 days after the trauma (AUC 0.70-0.84). In conclusion, younger trauma patients mount a stronger and more dynamic in vivo thrombin response than older patients. Across age groups, in vivo thrombin generation has a strong ability to predict death and/or thromboembolic events 30 days after injury.

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.

Management Strategies in Septic Coagulopathy: A Review of the Current Literature

One of the 'organs' that can be affected by sepsis is the coagulation system. Coagulopathy in sepsis may take the form of sepsis-induced coagulopathy (SIC) or sepsis-associated disseminated intravascular coagulation (DIC). It is important to identify SIC early, as at this stage of coagulopathy anticoagulants may be of the greatest benefit. The most recent diagnostic scoring systems for septic coagulopathy come from the International Society on Thrombosis and Hemostasis and the Japanese Association for Acute Medicine. Recommendations regarding the management of septic coagulopathy differ between organizations. Moreover, septic coagulopathy is an area of intense research in recent years. Therefore we searched three databases to review the most recent management strategies in septic coagulopathy. The mainstream management strategies in septic coagulopathy include the causal treatment of sepsis, unfractionated heparin, low-molecular-weight heparin, antithrombin, and recombinant human thrombomodulin. The last two have been associated with the highest survival benefit. Nevertheless, the indiscriminate use of these anticoagulants should be avoided due to the lack of mortality benefit and increased risk of bleeding. The early diagnosis of SIC and monitoring of coagulation status during sepsis is crucial for the timely management and selection of the most suitable treatment at a time. New directions in septic coagulopathy include new diagnostic biomarkers, dynamic diagnostic models, genetic markers for SIC management, and new therapeutic agents. These new research avenues may potentially result in timelier SIC diagnosis and improved management of all stages of septic coagulopathy by making it more effective, safe, and personalized.

Coagulation Disorders in Sepsis and COVID-19-Two Sides of the Same Coin? A Review of Inflammation-Coagulation Crosstalk in Bacterial Sepsis and COVID-19

Sepsis is a major cause of morbidity and mortality worldwide. Sepsis-associated coagulation disorders are involved in the pathogenesis of multiorgan failure and lead to a subsequently worsening prognosis. Alongside the global impact of the COVID-19 pandemic, a great number of research papers have focused on SARS-CoV-2 pathogenesis and treatment. Significant progress has been made in this regard and coagulation disturbances were once again found to underlie some of the most serious adverse outcomes of SARS-CoV-2 infection, such as acute lung injury and multiorgan dysfunction. In the attempt of untangling the mechanisms behind COVID-19-associated coagulopathy (CAC), a series of similarities with sepsis-induced coagulopathy (SIC) became apparent. Whether they are, in fact, the same disease has not been established yet. The clinical picture of CAC shows the unique feature of an initial phase of intravascular coagulation confined to the respiratory system. Only later on, patients can develop a clinically significant form of systemic coagulopathy, possibly with a consumptive pattern, but, unlike SIC, it is not a key feature. Deepening our understanding of CAC pathogenesis has to remain a major goal for the research community, in order to design and validate accurate definitions and classification criteria.

Communication from the Scientific and Standardization Committee of the International Society on Thrombosis and Haemostasis on sepsis-induced coagulopathy in the management of sepsis

Disseminated intravascular coagulation (DIC) is a life-threatening complication in sepsis and other critical conditions. The International Society on Thrombosis and Haemostasis (ISTH) released the diagnostic criteria for overt DIC in 2001. Since then, ISTH overt DIC has been used as the global standard criterion for a decompensated stage of DIC. Because detecting an earlier stage of DIC would be useful for therapeutic considerations, the scientific standardization committees of the ISTH introduced the sepsis-induced coagulopathy (SIC) scoring system in 2019. The SIC scoring system is specifically designed to detect the compensated phase of DIC in sepsis, which can lead to overt DIC with disease progression. Studies examining the performance of the SIC scoring system have reported its usefulness over the past 5 years. The reported incidence of SIC was approximately 60% in patients with sepsis, which was twice as much as that of overt DIC. Almost all patients with overt DIC were diagnosed with SIC earlier. The reported mortality of SIC was ≥30% and, thus, can be used for patient selection for anticoagulant therapy. Despite the limited data, some continue to suggest the potential efficacy of anticoagulant therapy in patients with SIC. Although heparin, antithrombin, and thrombomodulin are the candidates for anticoagulation, none of them have proven to be effective with robust evidence, and future trials are warranted.

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.

Current sepsis therapeutics

Management of the patient with sepsis comprises three key branches: control of the underlying infection, haemodynamic stabilization, and modulation of the host response. Each aspect should be considered in all patients and, when relevant, managed at the same time. Infection control is applicable to all patients with sepsis and will include antibiotic therapy and often surgical intervention to remove an infectious source. Haemodynamic support involves fluid administration in all patients and vasoactive agents in patients with associated circulatory shock. Noradrenaline is the first choice vasopressor agent; inotropic agents, usually dobutamine, may be added in case of myocardial depression. No interventions directed at individual components of the host response to sepsis have yet been shown to improve outcomes, but glucocorticoids and vasopressin have a global impact on the response and can thus be considered in this category. A move toward more personalized treatment is needed across all three arms of sepsis management.

Gaps and opportunities in sepsis translational research

Infection initiates sepsis, but the clinical disease arises through the innate immune response of the host. A rapidly evolving understanding of the biology of that response has not been paralleled by the development of successful new treatment. The COVID-19 pandemic has begun to change this revealing the promise of distinct therapeutic approaches and the feasibility of new approaches to evaluate them. We review the history of mediator-targeted therapy for sepsis and explore the conceptual, biological, technological, and organizational challenges that must be addressed to enable the development of effective treatments for a leading cause of global morbidity and mortality.

Effect of anticoagulant and platelet inhibition on the risk of bacteremia among patients with acute pyelonephritis: a retrospective cohort study

Background

An increasing number of patients are being prescribed anticoagulants and platelet inhibitors (antithrombotic treatment). Basic research has suggested an association between antithrombotic treatment and bacteremia during kidney infection. Here, we investigated the association between antithrombotic treatment, bacteremia and acute kidney injury in patients with acute pyelonephritis.

Methods

A retrospective cohort study was conducted in a large university hospital in Sweden. Data were retrieved from electronic medical records for adult patients with acute pyelonephritis in 2016. The main outcome was bacteremia and secondary outcome acute kidney injury. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated through multiple logistic regression. Treatment with different groups of antithrombotic agents were compared to no antithrombotic treatment.

Results

1814 patients with acute pyelonephritis were included, in whom bacteremia developed in 336 (18.5%). Low-molecular-weight heparin (LMWH) at prophylactic doses was associated with a lower risk of bacteremia, compared to no antithrombotic treatment (OR 0.5; 95% CI 0.3–0.7). Other antithrombotic treatments were not associated with a risk of bacteremia. Additionally, patients with prophylactic doses of LMWH had a lower risk of acute kidney injury (OR 0.5; 95% CI 0.3–0.8).

Conclusions

We found no association between antithrombotic treatment and an increased risk of bacteremia during acute pyelonephritis. Conversely, patients with prophylactic doses of LMWH had a slightly reduced risk of bacteremia. LMWH at prophylactic doses was also associated with a lower risk of acute kidney injury. Our results suggest that it is safe to continue antithrombotic treatment during acute pyelonephritis, in regards to bacteremia and acute kidney injury risk.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07474-4.

Web-based application for predicting the potential target phenotype for recombinant human thrombomodulin therapy in patients with sepsis: analysis of three multicentre registries

A recent randomised controlled trial failed to demonstrate a beneficial effect of recombinant human thrombomodulin (rhTM) on sepsis. However, there is still controversy in the effects of rhTM for sepsis due to the heterogeneity of the study population. We previously identified patients with a distinct phenotype that could be a potential target of rhTM therapy (rhTM target phenotype). However, for application in the clinical setting, a simple tool for determining this target is necessary. Thus, using three multicentre sepsis registries, we aimed to develop and validate a machine learning model for predicting presence of the target phenotype that we previously identified for targeted rhTM therapy. The predictors were platelet count, PT-INR, fibrinogen, fibrinogen/fibrin degradation products, and D-dimer. We also implemented the model as a web-based application. Two of the three registries were used for model development (n = 3694), and the remaining registry was used for validation (n = 1184). Approximately 8-9% of patients had the rhTM target phenotype in each cohort. In the validation, the C statistic of the developed model for predicting the rhTM target phenotype was 0.996 (95% CI 0.993-0.998), with a sensitivity of 0.991 and a specificity of 0.967. Among patients who were predicted to have the potential target phenotype (predicted target patients) in the validation cohort (n = 142), rhTM use was associated with a lower in-hospital mortality (adjusted risk difference, - 31.3% [- 53.5 to - 9.1%]). The developed model was able to accurately predict the rhTM target phenotype. The model, which is available as a web-based application, could profoundly benefit clinicians and researchers investigating the heterogeneity in the treatment effects of rhTM and its mechanisms.

Performance evaluation of thrombus molecular markers thrombomodulin, thrombin-antithrombin complex, plasmin-α2-plasmin inhibitor complex, and tissue plasminogen activator-inhibitor complex by a chemiluminescence analyzer

OBJECTIVE

To comprehensively evaluate the primary performance regarding the task of detecting thrombomodulin (TM), thrombin-antithrombin complex (TAT), plasmin-α2-plasmin inhibitor complex (PIC), and tissue plasminogen activator/plasminogen activator inhibitor-1 complex (t-PAIC) by Sysmex HisCL5000 high sensitivity chemiluminescence analyzer.

METHODS

The performance of the chemiluminescence analyzer was evaluated according to the Clinical and Laboratory Standards Institute (CLSI) documents for in-batch precision, daytime precision, carryover rate, linearity, and reference range.

RESULTS

The intra-batch and inter-day variation coefficients of the test items were all less than 5 %, and the contamination rate of each index was less than 10 %. The linear verification analysis showed that the correlation coefficients of TM, TAT, PIC, and t-PAIC were 0.9968, 0.9988, 0.9981, and 0.9930, respectively. The project recommended reference range was applicable to our laboratory.

CONCLUSION

The high-sensitivity chemiluminescence analyzer has good performance in the detection of TM, TAT, PIC, and t-PAIC and is suitable for the detection of clinical specimens. HIPPOKRATIA 2022, 26 (2):78-82.

Nevertheless, the importance of coagulation abnormalities should be emphasized in international sepsis guidelines

It is generally accepted that a coagulation/fibrinolysis disorder is involved in the pathogenesis of sepsis, and the association of disseminated intravascular coagulation (DIC) and poor outcomes have been reported. Based on these findings, recently released "Japanese Surviving Sepsis Campaign guidelines 2020" recommend the diagnosis of DIC and the application of anticoagulants for sepsis-associated DIC. Meanwhile, the updated "International Guidelines for the Management of Sepsis and Septic Shock 2021" did not mention coagulation abnormalities or DIC. Because management strategies continue to evolve to provide improved outcomes in sepsis, the role of adjunctive anticoagulant treatment should be included in subsequent international guidelines.

Effect of Recombinant Human Soluble Thrombomodulin on Coagulation-Related Variables in Patients With Sepsis-Induced Disseminated Intravascular Coagulation: A Retrospective Observational Study

To evaluate associations among coagulation-related variables, resolution of disseminated intravascular coagulation (DIC) and mortality, we retrospectively investigated 123 patients with sepsis-induced DIC treated with recombinant human soluble thrombomodulin (rTM). Changes in coagulation-related variables before and after treatment with rTM were examined. Further, associations between coagulation-related variables and DIC resolution were evaluated. The platelet count, prothrombin international normalized ratio (PT-INR), and fibrin/fibrinogen degradation products (FDP) significantly (p < .001) improved after rTM administration in survivors (n = 98), but not in nonsurvivors (n = 25). However, the DIC score significantly (p < .001) reduced in survivors and in nonsurvivors. Among coagulation-related variables examined before rTM, only PT-INR was significantly (p = .0395) lower in survivors than in nonsurvivors, and PT-INR before rTM was significantly (p = .0029) lower in patients attaining than not attaining DIC resolution (n = 87 and 36, respectively). The 28-day mortality was significantly lower in patients attaining than not attaining DIC resolution (11.5% vs 41.7%, p = .0001). In conclusion, the initiation of rTM administration before marked PT-INR elevation may be important to induce DIC resolution and thus to decrease mortality in patients with sepsis-induced DIC. Conversely, the treatment with rTM in patients with marked PT-INR elevation may be not so effective in achieving such goals.

Signaling pathways and intervention therapies in sepsis

Sepsis is defined as life-threatening organ dysfunction caused by dysregulated host systemic inflammatory and immune response to infection. Over decades, advanced understanding of host-microorganism interaction has gradually unmasked the genuine nature of sepsis, guiding toward new definition and novel therapeutic approaches. Diverse clinical manifestations and outcomes among infectious patients have suggested the heterogeneity of immunopathology, while systemic inflammatory responses and deteriorating organ function observed in critically ill patients imply the extensively hyperactivated cascades by the host defense system. From focusing on microorganism pathogenicity, research interests have turned toward the molecular basis of host responses. Though progress has been made regarding recognition and management of clinical sepsis, incidence and mortality rate remain high. Furthermore, clinical trials of therapeutics have failed to obtain promising results. As far as we know, there was no systematic review addressing sepsis-related molecular signaling pathways and intervention therapy in literature. Increasing studies have succeeded to confirm novel functions of involved signaling pathways and comment on efficacy of intervention therapies amid sepsis. However, few of these studies attempt to elucidate the underlining mechanism in progression of sepsis, while other failed to integrate preliminary findings and describe in a broader view. This review focuses on the important signaling pathways, potential molecular mechanism, and pathway-associated therapy in sepsis. Host-derived molecules interacting with activated cells possess pivotal role for sepsis pathogenesis by dynamic regulation of signaling pathways. Cross-talk and functions of these molecules are also discussed in detail. Lastly, potential novel therapeutic strategies precisely targeting on signaling pathways and molecules are mentioned.

Endothelial dysfunction: a therapeutic target in bacterial sepsis?

INTRODUCTION

Endothelial cells maintain vascular integrity, tone, and patency and have important roles in hemostasis and inflammatory responses. Although some degree of endothelial dysfunction with increased vascular permeability may be necessary to control local infection, excessive dysfunction plays a central role in the pathogenesis of sepsis-related organ dysfunction and failure as it results in dysregulated inflammation, vascular leakage, and abnormal coagulation. The vascular endothelium has thus been proposed as a potential target for therapeutic intervention in patients with sepsis.

AREAS COVERED

Different mechanisms underlying sepsis-related dysfunction of the vascular endothelium are discussed, including glycocalyx shedding, nitrosative stress, and coagulation factors. Potential therapeutic implications of each mechanism are mentioned.

EXPERT OPINION

Multiple targets to protect or restore endothelial function have been suggested, but endothelium-driven treatments remain a future potential at present. As some endothelial dysfunction and permeability may be necessary to remove infection and repair damaged tissue, targeting the endothelium may be a particular challenge. Ideally, therapies should be guided by biomarkers related to that specific pathway to ensure they are given only to patients most likely to respond. This enrichment based on biological plausibility and theragnostics will increase the likelihood of a beneficial response in individual patients and enable more personalized treatment.

The Roles of Coagulation Disorder and Microthrombosis in Sepsis: Pathophysiology, Diagnosis, and Treatment

The diagnostic criteria of overt disseminated intravascular coagulation (DIC) were established by the International Society on Thrombosis and Haemostasis (ISTH) in 2001. Since then, DIC has long been associated with adverse outcomes. However, recent advances in sepsis shed light on the role of coagulation disorders in the progression of sepsis. Currently, inflammation and coagulation are recognized as the two drivers that promote organ dysfunction in sepsis and septic shock. The ISTH has published new diagnostic criteria for improved management, namely sepsis-induced coagulopathy (SIC), in 2017. SIC is a pragmatic scoring system composed of platelet count, prothrombin time, and organ dysfunction score to detect the early-stage of sepsis-associated DIC. Since overt DIC represents an uncompensated coagulation disorder, a two-step approach using SIC and overt DIC criteria is a novel strategy to evaluate the severity and manage this challenging complication. Although there is no globally agreed on anticoagulant therapy for DIC, the Japanese Surviving Sepsis Campaign Guidelines 2020 recommend using antithrombin and recombinant thrombomodulin for sepsis associated DIC. Since research in this area has been previously reported, an international collaborative study is necessary to develop future diagnostic tools and treatment strategies.

Specific detection of high mobility group box 1 degradation product with a novel ELISA

BACKGROUND

During sepsis or sterile tissue injury, the nuclear protein high mobility group box 1 (HMGB1) can be released to the extracellular space and ultimately into systemic circulation, where it mediates systemic inflammation and remote organ failure. The proinflammatory effects of HMGB1 can be suppressed by recombinant thrombomodulin (rTM), in part through a mechanism involving thrombin-rTM-mediated degradation of HMGB1. Given that HMGB1 is proinflammatory but the HMGB1 degradation product (desHMGB1) is not, an analytical method that discriminates between these two molecules may provide a more in-depth understanding of HMGB1-induced pathogenicity as well as rTM-mediated therapeutic efficiency.

METHODS

A peptide that has a shared amino-terminal structure with desHMGB1 was synthesized. C3H/lpr mice were immunized with the desHMGB1 peptide conjugate, and antibody-secreting hybridoma cells were developed using conventional methods. The reactivity and specificity of the antibodies were then analyzed using antigen-coated enzyme-linked immunosorbent assay (ELISA) as well as antibody-coated ELISA. Next, plasma desHMGB1 levels were examined in a cecal ligation and puncture (CLP)-induced septic mouse model treated with rTM.

RESULTS

Through a series of screening steps, we obtained a monoclonal antibody that recognized desHMGB1 but did not recognize intact HMGB1. ELISA using this antibody specifically detected desHMGB1, which was significantly increased in CLP-induced septic mice treated with rTM compared with those treated with saline.

CONCLUSIONS

In this study, we obtained a desHMGB1-specific monoclonal antibody. ELISA using the novel monoclonal antibody may be an option for the in-depth analysis of HMGB1-induced pathogenicity as well as rTM-mediated therapeutic efficiency.

An Experience of Multiple Hematomas in a Coronavirus Disease-19 Patient Administered with ART-123 and Heparin

Background

Anticoagulant therapy for patients with severe coronavirus disease (COVID-19) pneumonia is considered to improve the hypercoagulable and inflammatory state. However, bleeding complications should also be considered.

Case Presentation

A 77-year-old man with a history of falls was diagnosed with COVID-19. Owing to his severe condition, he was intubated and transferred to our hospital for intensive care. Favipiravir, tocilizumab, unfractionated heparin, and ART-123 were administered to treat COVID-19 and manage the antithrombotic prophylaxis for paroxysmal atrial fibrillation (Af). On the 6th day after admission, a hematoma was noted on the left chest wall. Computed tomography (CT) revealed multiple hematomas, including hematomas on his chest wall and obturatorius internus muscle. Emergency angiography transcatheter embolization (TAE) was performed. The patient was transferred to another hospital 23 days after TAE, without complications.

Conclusion

Our findings show that anticoagulation therapy and a history of falls induced multiple hematomas in a COVID-19 patient and that the condition was managed with TAE. When anticoagulants are considered in the management of Af and COVID-19 associated coagulopathy, it is necessary to closely monitor potential bleeding complications.

Efficacy and safety of human soluble thrombomodulin (ART-123) for treatment of patients in France with sepsis-associated coagulopathy: post hoc analysis of SCARLET

BACKGROUND

The phase 3 multinational SCARLET study evaluated the efficacy and safety of a recombinant human soluble thrombomodulin (ART-123) for treatment of sepsis-associated coagulopathy (SAC), which correlates with increased mortality risk in patients with sepsis. Although no significant reduction in mortality was observed with ART-123 compared with placebo in the full analysis set (FAS), an efficacy signal of ART-123 was observed in subgroups of patients who sustained coagulopathy until the first treatment and those not administered concomitant heparin. Post hoc analysis was performed of patients treated in France, the country with the largest enrollment (19% of the FAS) and consistent patient enrollment throughout the study duration.

METHODS

Adult patients with SAC (international normalized ratio > 1.4; platelets > 30 × 10⁹/L to < 150 × 10⁹/L or platelet decrease > 30% within 24 h) and evidence of bacterial infection were included. The primary efficacy outcome was 28-day all-cause mortality. Safety outcomes included adverse, serious adverse, and major bleeding events. This analysis assessed patient characteristics and efficacy and safety outcomes in France compared with the rest of the world (ROW; excluding France). Mortality rates were assessed in patients in France or the ROW with characteristics previously associated with ART-123 efficacy.

RESULTS

Baseline characteristics were similar between France and the ROW, but some measurements of disease severity were higher in patients in France. The 28-day all-cause mortality absolute risk reductions (ARRs) with ART-123 were 8.3% in France and 1.1% in the ROW. The greater ARR in France may be related to a higher rate of sustained coagulopathy and lower rate of heparin use. In France and the ROW, 84.6% and 78.0% of patients sustained coagulopathy from the time of initial SAC diagnosis to first treatment with the study drug, and 65.8% and 43.9% did not receive heparin, respectively. The ARRs for these subgroups of patients in France were 13.4% and 16.6%, respectively. Safety of ART-123 was comparable between France and the ROW.

CONCLUSIONS

Results from this exploratory analysis suggest that patients with sustained SAC not receiving concomitant heparin may benefit from ART-123, a fact that should be confirmed in future studies with more restrictive inclusion criteria.

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.

Preoperative disseminated intravascular coagulation complicated by thoracic aortic aneurysm treated using recombinant human soluble thrombomodulin: A case report

RATIONALE

Chronic disseminated intravascular coagulation (DIC) associated with thoracic aortic aneurysm is characterized by enhanced fibrinolysis and is thought to be stable in the compensated/asymptomatic stage, with few bleeding symptoms. However, DIC can lead to decompensated/hemorrhagic stage disseminated intravascular coagulation, resulting in severe bleeding diathesis, and there is currently no established strategy for treatment of DIC in aortic aneurysms.

PATIENT CONCERNS

A 77-year-old woman underwent angiography and cardiac catheterization, before descending aortic replacement surgery. She developed DIC in postprocedure week 2 with extensive, uncontrollable massive subcutaneous hemorrhage.

DIAGNOSES

Her acute-phase DIC score was 7 points, and the risk of mortality within 30 days after surgery according to the JapanSCORE was estimated to be 33.6%.

INTERVENTIONS

Therapy was a combination of recombinant human soluble thrombomodulin (rhTM) and an aortic stent-graft treatment.

OUTCOMES

Short-term improvements were seen in both DIC and bleeding diathesis. The thoracic aortic aneurysm with severe DIC was eventually corrected by administration of rhTM.

LESSONS

We report the use of rhTM as an effective, novel anticoagulant drug with anti-inflammatory activity for treating DIC with suppressed fibrinolysis, which is typically associated with sepsis. In patients with a high hemorrhagic diathesis, in whom preoperative control of DIC cannot be achieved with conventional anticoagulation and radical surgical repair cannot be performed, a combination of rhTM and endovascular therapy may be a powerful new treatment option.

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.

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.