Recombinant human soluble thrombomodulin improves mortality in patients with sepsis especially for severe coagulopathy: a retrospective study

Machine learning-based prediction model for hypofibrinogenemia after tigecycline therapy

BACKGROUND

In clinical practice, the incidence of hypofibrinogenemia (HF) after tigecycline (TGC) treatment significantly exceeds the probability claimed by drug manufacturers.

OBJECTIVE

We aimed to identify the risk factors for TGC-associated HF and develop prediction and survival models for TGC-associated HF and the timing of TGC-associated HF.

METHODS

This single-center retrospective cohort study included 222 patients who were prescribed TGC. First, we used binary logistic regression to screen the independent factors influencing TGC-associated HF, which were used as predictors to train the extreme gradient boosting (XGBoost) model. Receiver operating characteristic curve (ROC), calibration curve, decision curve analysis (DCA), and clinical impact curve analysis (CICA) were used to evaluate the performance of the model in the verification cohort. Subsequently, we conducted survival analysis using the random survival forest (RSF) algorithm. A consistency index (C-index) was used to evaluate the accuracy of the RSF model in the verification cohort.

RESULTS

Binary logistic regression identified nine independent factors influencing TGC-associated HF, and the XGBoost model was constructed using these nine predictors. The ROC and calibration curves showed that the model had good discrimination (areas under the ROC curves (AUC) = 0.792 [95% confidence interval (CI), 0.668-0.915]) and calibration ability. In addition, DCA and CICA demonstrated good clinical practicability of this model. Notably, the RSF model showed good accuracy (C-index = 0.746 [95%CI, 0.652-0.820]) in the verification cohort. Stratifying patients treated with TGC based on the RSF model revealed a statistically significant difference in the mean survival time between the low- and high-risk groups.

CONCLUSIONS

The XGBoost model effectively predicts the risk of TGC-associated HF, whereas the RSF model has advantages in risk stratification. These two models have significant clinical practical value, with the potential to reduce the risk of TGC therapy.

Rethinking coagulation: from enzymatic cascade and cell-based reactions to a convergent model involving innate immune activation

ABSTRACT

Advancements in the conceptual thinking of hemostasis and thrombosis have been catalyzed by major developments within health research over several decades. The cascade model of coagulation was first described in the 1960s, when biochemistry gained prominence through innovative experimentation and technical developments. This was followed by the cell-based model, which integrated cellular coordination to the enzymology of clot formation and was conceptualized during the growth period in cell biology at the turn of the millennium. Each step forward has heralded a revolution in clinical therapeutics, both in procoagulant and anticoagulant treatments to improve patient care. In current times, the COVID-19 pandemic may also prove to be a catalyst: thrombotic challenges including the mixed responses to anticoagulant treatment and the vaccine-induced immune thrombotic thrombocytopenia have exposed limitations in our preexisting concepts while simultaneously demanding novel therapeutic approaches. It is increasingly clear that innate immune activation as part of the host response to injury is not separate but integrated into adaptive clot formation. Our review summarizes current understanding of the major molecules facilitating such a cross talk between immunity, inflammation and coagulation. We demonstrate how such effects can be layered upon the cascade and cell-based models to evolve conceptual understanding of the physiology of immunohemostasis and the pathology of immunothrombosis.

Recombinant Human Thrombomodulin Reduces Mortality and Acute Lung Injury Caused by Septic Peritonitis in Rats

This study aimed to investigate the therapeutic effects of recombinant human thrombomodulin (rhTM) on acute lung injury (ALI) caused by sepsis in rats. Rats that underwent cecal ligation and puncture (CLP) were treated with or without rhTM, and then mortality was analyzed. In another set of experiments, ALI was assessed. Furthermore, microthrombosis in the lungs was investigated by immunohistochemistry. Moreover, plasma inflammatory and anti-inflammatory cytokines, such as TNF-α, high-mobility group box chromosomal protein 1 (HMGB-1), and IL-10, were evaluated by ELISA. Production of TNF-α and HMGB-1 by isolated tissue macrophages (Mφs) was assessed in vitro. Mortality after CLP was significantly improved by rhTM treatment. In addition, rhTM treatment improved the wet/dry weight ratio of the lungs, the pulmonary microvascular permeability, and the lung injury scores in animals that underwent CLP. Microthrombosis was detected in the lungs after CLP. These pathophysiological changes were blunted by rhTM treatment. Increased plasma TNF-α and HMGB-1 levels were blunted by rhTM treatment; however, the anti-inflammatory cytokine IL-10 was significantly greater in the rhTM(+) group than in the rhTM(-) group. Increased TNF-α and HMGB-1 production by the tissue Mφs stimulated with LPS were significantly blunted by rhTM treatment in vitro, but the production of IL-10 by the tissue Mφs was not changed in the cells incubated with rhTM. Overall, rhTM improved the mortality caused by septic peritonitis. The possible mechanisms are most likely anti-inflammatory and anticoagulant effects, which lead to the prevention of ALI.

Emerging therapeutic targets for sepsis

Introduction: Sepsis is characterized by a dysregulated host response to infection. Sepsis-associated morbidity/mortality demands concerted research efforts toward therapeutic interventions which are reliable, broadly effective, and etiologically based. More intensive and extensive investigations on alterations in cellular signaling pathways, gene targeting as a means of modifying the characteristic hyper and/or hypo-immune responses, prevention through optimization of the microbiome, and the molecular pathways underlying the septic immune response could improve outcomes.] Areas covered: The authors discuss key experimental mammalian models and clinical trials. They provide an evaluation of evolving therapeutics in sepsis and how they have built upon past and current treatments. Relevant literature was derived from a PubMed search spanning 1987-2020.Expert opinion: Given the complex nature of sepsis and the elicited immune response, it is not surprising that a single cure-all therapeutic intervention, which is capable of effectively and reliably improving patient outcomes has failed to emerge. Innovative approaches seek to address not only the disease process but modify underlying patient factors. A true improvement in sepsis-associated morbidity/mortality will require a combination of unique therapeutic modalities.

Recombinant Human Thrombomodulin Has Additive Effects in Septic Patients Undergoing Continuous Hemodiafiltration Due to Intestinal Perforation

BACKGROUND

Disseminated intravascular coagulation (DIC) is associated with high mortality in patients with severe sepsis. The purpose of this study was to investigate the effects of recombinant human thrombomodulin (rhTM) in septic patients undergoing continuous hemodiafiltration (CHDF). Furthermore, effects of rhTM in acute lung injury, the first target organ in sepsis, were investigated using a sepsis model in rats.

METHODS

Clinical laboratory data, and the DIC, Sequential Organ Failure Assessment (SOFA), and Acute Physiologic and Chronic Health Evaluation (APACHE) II scores were compared between patients undergoing CHDF alone (rhTM- group; n = 23 cases) and patients undergoing CHDF treated with rhTM (rhTM+ group; n = 21 cases). Rats underwent cecal ligation and puncture (CLP) treated with or without rhTM, and acute lung injury (ALI) was analyzed. Production of TNF-α by isolated tissue macrophages (Mfs) was assessed.

RESULTS

The numbers of leukocytes, and C-reactive protein and D-dimer levels were significantly suppressed, and platelet counts recovered significantly faster in the rhTM+ group compared with the rhTM- group. The DIC score was reduced in both groups. The SOFA and APACHE II scores gradually reduced in the rhTM+ group. The CHDF treatment and ICU admission periods were shortened in the rhTM+ group compared with the rhTM- group. Treatment of rhTM was an independent factor for CHDF treatment period by multivariate analyses. CLP-induced ALI was significantly improved by rhTM. Increased TNF-α production by tissue Mfs was significantly suppressed by rhTM in vivo and in vitro.

CONCLUSION

Additive effects of rhTM treatment were observed in septic patients undergoing CHDF.

The hypercoagulable state in COVID-19: Incidence, pathophysiology, and management

The 2019 coronavirus disease (COVID-19) presents with a large variety of clinical manifestations ranging from asymptomatic carrier state to severe respiratory distress, multiple organ dysfunction and death. While it was initially considered primarily a respiratory illness, rapidly accumulating data suggests that COVID-19 results in a unique, profoundly prothrombotic milieu leading to both arterial and venous thrombosis. Consistently, elevated D-dimer level has emerged as an independent risk factor for poor outcomes, including death. Several other laboratory markers and blood counts have also been associated with poor prognosis, possibly due to their connection to thrombosis. At present, the pathophysiology underlying the hypercoagulable state is poorly understood. However, a growing body of data suggests that the initial events occur in the lung. A severe inflammatory response, originating in the alveoli, triggers a dysfunctional cascade of inflammatory thrombosis in the pulmonary vasculature, leading to a state of local coagulopathy. This is followed, in patients with more severe disease, by a generalized hypercoagulable state that results in macro- and microvascular thrombosis. Of concern, is the observation that anticoagulation may be inadequate in many circumstances, highlighting the need for alternative or additional therapies. Numerous ongoing studies investigating the pathophysiology of the COVID-19 associated coagulopathy may provide mechanistic insights that can direct appropriate interventional strategies.

Sepsis therapies: learning from 30 years of failure of translational research to propose new leads

Sepsis has been identified by the World Health Organization (WHO) as a global health priority. There has been a tremendous effort to decipher underlying mechanisms responsible for organ failure and death, and to develop new treatments. Despite saving thousands of animals over the last three decades in multiple preclinical studies, no new effective drug has emerged that has clearly improved patient outcomes. In the present review, we analyze the reasons for this failure, focusing on the inclusion of inappropriate patients and the use of irrelevant animal models. We advocate against repeating the same mistakes and propose changes to the research paradigm. We discuss the long-term consequences of surviving sepsis and, finally, list some putative approaches-both old and new-that could help save lives and improve survivorship.

Role of Antithrombin III and Tissue Factor Pathway in the Pathogenesis of Sepsis

The pathobiology of the septic process includes a complex interrelationship between inflammation and the coagulations system. Antithrombin (AT) and tissue factor are important components of the coagulation system and have potential roles in the production and amplification of sepsis. Sepsis is associated with a decrease in AT levels, and low levels are also associated with the development of multiple organ failure and death. Treatment strategies incorporating AT replacement therapy in sepsis and septic shock have not resulted in an improvement in survival or reversal of disseminated intravascular coagulation.

Human Soluble Recombinant Thrombomodulin, ART-123, Resolved Early Phase Coagulopathies, but Did Not Significantly Alter the 28 Day Outcome in the Treatment of DIC Associated with Infectious Systemic Inflammatory Response Syndromes

Disseminated intravascular coagulation (DIC) is a catastrophic systemic disorder of coagulation, resulting in uncontrollable bleeding, multiple organ failure, and death. Sepsis is one of the common causes of DIC. Despite many attempts to correct these coagulation pathologies, no adjunctive treatments have been shown to improve the mortality of DIC associated with sepsis. Although some clinical studies showed a recently developed human recombinant thrombomodulin, ART-123, might be effective in the treatment of DIC, few randomized, placebo-controlled studies have been conducted. In this study, we treated 60 DIC patients associated with systemic inflammatory response syndrome (SIRS) using ART-123 (n = 29) or saline as a placebo (n = 31). The basal clinical characteristics were similar in both groups. We compared clinical severity scores and DIC score in acute phase, and 28 day mortality between the two groups. Our study demonstrated the DIC score improved a few days earlier in the ART-123 group than the placebo group, and there were no major life-threatening adverse events in both groups. The overall survival rate at day 28 was not significantly altered. In conclusion, ART-123 can be used safely in DIC associated with infectious SIRS patients; however, its true efficacy in the treatment of DIC needs to be further investigated.