Bacterial Porins and Their Procoagulant Role: Implication in the Pathophysiology of Several Thrombotic Complications during Sepsis.

The association between sepsis and thrombotic complications is still not well known. Different mechanisms have been shown to be involved in the sepsis-induced prothrombotic state, but clinical scenarios may differ. In this review, we have summarized the role that bacterial products such as porins and toxins can have in the induction of the prothrombotic state during sepsis and the interaction that they can have with each other. Furthermore, the above-mentioned mechanisms might be involved in the pattern of the clinical presentation of thrombotic events during bacterial sepsis, which would secondarily explain the association between sepsis and venous thromboembolism, the association between sepsis and disseminated intravascular coagulation, and the association between sepsis and microangiopathic venous thromboembolism.

Coagulopatías por consumo en el paciente con cáncer / Consumptive Coagulopathies in the Patient with Cancer

Introducción: Los trastornos de la coagulación durante el perioperatorio de pacientes oncológicos, son eventos más frecuentes de lo que se conoce en realidad, debido a que un gran número de estos transitan de forma inadvertida. Objetivo: Describir los factores fisiopatológicos que propician la ocurrencia de las coagulopatías adquiridas por consumo durante el perioperatorio del paciente oncológico. Métodos: Se realizó una revisión narrativa, en idiomas español e inglés, se utilizaron como fuente de búsqueda las bases de datos Ebsco, SciElo, Pubmed, Cubmed, Hinary, durante el período de enero a marzo de 2022, y el referenciador Zotero versión 5.0. Resultados: Para comprender qué pasa en el paciente con cáncer en relación con las coagulopatías por consumo es necesario entender la fisiología de los mecanismos de la coagulación. En este sentido, se pueden observar tanto trastornos trombóticos como hemorrágicos, por el incremento del factor tisular que determina la formación de trombina y el fallo de los mecanismos antifibrinolíticos. También, factores como la radioterapia, la quimioterapia y la transfusión de hemocomponentes, aumentan el riesgo de padecerlas. Conclusiones: la coagulopatía por consumo en el paciente oncológico es una entidad multifactorial, compleja y dinámica, en la que se debe pensar y diagnosticar para evitar complicaciones graves en el período perioperatorio.

Introduction: Coagulation disorders during the perioperative period of cancer patients are more frequent events than is actually known, due to the fact that a large number of these go unnoticed. Objective: To describe the pathophysiological factors that favor the occurrence of consumption-acquired coagulopathies during the perioperative period of cancer patients. Methods: A narrative review was carried out, in Spanish and English, using the Ebsco, Scielo, Pubmed, Cubmed, Hinary databases as a search source, during the period from January to March 2022, and the Zotero version 5.0 referer. 96.3. Results: To understand what happens in cancer patients in relation to consumption coagulopathies, it is necessary to understand the physiology of coagulation mechanisms. In this sense, both thrombotic and hemorrhagic disorders can be observed, due to the increase in the tissue factor that determines the formation of thrombin and the failure of antifibrinolytic mechanisms. Also, factors such as radiotherapy, chemotherapy and transfusion of blood components, increase the risk of suffering from them. Conclusions: consumption coagulopathy in cancer patients is a multifactorial, complex and dynamic entity, which must be considered and diagnosed to avoid serious complications in the perioperative period.

Comprehensive Analyses of Coagulation Parameters in Patients with Vascular Anomalies.

BACKGROUND: Vascular anomalies comprise a diverse group of rare diseases with altered blood flow and are often associated with coagulation disorders. The most common example is a localized intravascular coagulopathy in venous malformations leading to elevated D-dimers. In severe cases, this may progress to a disseminated intravascular coagulopathy with subsequent consumption of fibrinogen and thrombocytes predisposing to serious bleeding. A separate coagulopathy is the Kasabach-Merritt phenomenon in kaposiform hemangioendothelioma characterized by platelet trapping leading to thrombocytopenia and eventually consumptive coagulopathy. Our previous work showed impaired von Willebrand factor and platelet aggregometry due to abnormal blood flow, i.e., in ventricular assist devices or extracorporeal membrane oxygenation. With altered blood flow also present in vascular anomalies, we hypothesized that, in particular, the von Willebrand factor parameters and the platelet function may be similarly impacted. METHODS: We prospectively recruited 73 patients with different vascular anomaly entities and analyzed their coagulation parameters. RESULTS: Acquired von Willebrand syndrome was observed in both of our patients with Kasabach-Merritt phenomenon. In six out of nine patients with complex lymphatic anomalies, both the vWF antigen and activity were upregulated. Platelet aggregometry was impaired in both patients with Kasabach-Merritt phenomenon and in seven out of eight patients with an arteriovenous malformation. CONCLUSIONS: The analysis of coagulation parameters in our patients with vascular anomalies advanced our understanding of the underlying pathophysiologies of the observed coagulopathies. This may lead to new treatment options for the, in part, life-threatening bleeding risks in these patients in the future.

Which Septic Shock Patients With Non-Overt DIC Progress to DIC After Admission? Point-of-Care Thromboelastography Testing.

BACKGROUND: Disseminated intravascular coagulation (DIC) is a life-threatening complication of septic shock; however, risk factors for its development after admission are unknown. Thromboelastography (TEG) can reflect coagulation disturbances in early non-overt DIC that are not detected by standard coagulation tests. This study investigated the risk factors including TEG findings as early predictors for DIC development after admission in septic shock patients with non-overt DIC. METHODS: This retrospective observation study included 295 consecutive septic shock patients with non-overt DIC at admission between January 2016 and December 2019. DIC was defined as an International Society on Thrombosis and Hemostasis (ISTH) score ≥ 5. The primary outcome was non-overt DIC at admission that met the ISTH DIC criteria within 3 days after admission. RESULTS: Of the 295 patients with non-overt DIC, 89 (30.2%) developed DIC after admission. The DIC group showed a higher ISTH score and 28-day mortality rate than the non-DIC group (2 vs. 3, P < 0.001; 13.6% vs. 27.0%, P = 0.008, respectively). The DIC rate increased with the ISTH score (7.7%, 13.3%, 15.8%, 36.5%, and 61.4% for scores of 0, 1, 2, 3, and 4, respectively). Among TEG values, the maximum amplitude (MA) was higher in the non-DIC group (P < 0.001). On multivariate analysis, an MA < 64 mm was independently associated with DIC development (odds ratio, 2.311; 95% confidence interval, 1.298-4.115). CONCLUSIONS: DIC more often developed among those with admission ISTH scores ≥ 3 and was associated with higher mortality rates. An MA < 64 mm was independently associated with DIC development in septic shock patients.

Chronic intravascular coagulation in liver cirrhosis predicts a high hemorrhagic risk.

OBJECTIVE: In liver cirrhosis, a complex coagulopathy does exist. The aim was to investigate whether a possible chronic consumption coagulopathy is the underlying phenomenon of the disease. PATIENTS AND METHODS: We measured endogenous thrombin generation with and without thrombomodulin (ETP ratio) along with D-Dimer in a group of consecutive 282 cirrhotic patients. Fibrinogen, Platelet count and the Hemorrhagic score were previously computed in the same patients. The ETP ratio represents the resistance to the anticoagulant activity of TM and should be considered as an index of a procoagulant imbalance. RESULTS: ETP ratio and D-Dimer showed higher values in the cirrhotic patients when compared to controls thus showing a hypercoagulable state. When the patients were divided based on the Hemorrhagic score >7, we found that Fibrinogen, ETP ratio, D-Dimer and the platelet count were significantly different between the two groups. Again, when we considered ETP ratio >0.88, the median value of the cirrhotic patients, all parameters, were statistically different between the two groups. D-Dimer were higher while fibrinogen and platelet count were statistically lower in cirrhotic patients with higher ETP ratio values. Even when the same patients were divided based on their platelet count ( 100 x 109/L) the results showed a similar behavior. ROC curves showed significant AUCs when the hemorrhagic score was challenged against Fibrinogen, D-Dimer, Platelet count and ETP ratio. CONCLUSIONS: In liver cirrhosis hypercoagulable state is associated with an increase in D-Dimer levels along with a decrease in fibrinogen and platelet count thus indicating a low-grade intravascular coagulation which predicts a high hemorrhagic risk.

Vaccine-Induced Immune Thrombotic Thrombocytopenia with Disseminated Intravascular Coagulation and Death following the ChAdOx1 nCoV-19 Vaccine.

Coronavirus is a novel human pathogen causing fulminant respiratory syndrome (COVID-19). Although COVID-19 is primarily a disease of the lungs with florid respiratory manifestations, there are increasing reports of cardiovascular, musculoskeletal, gastrointestinal, and thromboembolic complications. Developing an effective and reliable vaccine was emergently pursued to control the catastrophic spread of the global pandemic. We report a fatal case of vaccine-induced immune thrombotic thrombocytopenia (VITT) after receiving the first dose of the ChAdOx1 nCoV-19 vaccine. We attribute this fatal thrombotic condition to the vaccine due to the remarkable temporal relationship. The proposed mechanism of VITT is production of rogue antibodies against platelet factor-4 resulting in massive platelet aggregation. Healthcare providers should be aware of the possibility of such fatal complication, and the vaccine recipients should be warned about the symptoms of VITT.

Cardiovascular, hematological and neurosensory impact of COVID-19 and variants.

OBJECTIVE: The purpose of this article was to review our clinical experience with COVID-19 patients observed in the Cardiovascular Division of Pompidou Hospital (University of Paris, France) and the Department of Neurology of the Eastern Piedmont University (Novara, Italy), related to the impact on the cardiovascular, hematological, and neurologic systems and sense organs. PATIENTS AND METHODS: We sought to characterize cardiovascular, hematological, and neurosensory manifestations in patients with COVID-19 and variants. Special attention was given to initial signs and symptoms to facilitate early diagnosis and therapy. Indications of ECMO (extracorporeal membrane oxygenation) for cardiorespiratory support were evaluated. RESULTS: Preliminary neurosensorial symptoms, such as anosmia and dysgeusia, are useful for diagnosis, patient isolation, and treatment. Early angiohematological acro-ischemic syndrome includes hand and foot cyanosis, Raynaud digital ischemia phenomenon, skin bullae, and dry gangrene. This was associated with neoangiogenesis, vasculitis, and vessel thrombosis related to immune dysregulation, resulting from "cytokine storm syndrome". The most dangerous complication is disseminated intravascular coagulation, with mortality risks for both children and adults. CONCLUSIONS: COVID-19 is a prothrombotic disease with unique global lethality. A strong inflammatory response to viral infection severely affects cardiovascular and neurological systems, as well as respiratory, immune, and hematological systems. Rapid identification of acro-ischemic syndrome permits the treatment of disseminated intravascular coagulation complications. Early sensorial symptoms, such as gustatory and olfactory loss, are useful for COVID-19 diagnosis. New variants of SARS-CoV-2 are emerging, principally from United Kingdom, South Africa, and Brazil. These variants seem to spread more easily and quickly, which may lead to more cases of COVID.

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 topics regarding this difficult situation. EVIDENCE ACQUISITION: Online search of published medical literature through MEDLINE and Web of Science 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.

Complement activation and coagulopathy - an ominous duo in COVID19.

INTRODUCTION: COVID-19 has similarities to the Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS) outbreaks, as severe patients and non-survivors have frequently shown abnormal coagulation profiles. Immune-mediated pathology is a key player in this disease; hence, the role of the complement system needs assessment. The complement system and the coagulation cascade share an intricate network, where multiple mediators maintain a balance between both pathways. Coagulopathy in COVID-19, showing mixed features of complement-mediated and consumption coagulopathy, creates a dilemma in diagnosis and management. AREAS COVERED: Pathophysiology of coagulopathy in COVID-19 patients, with a particular focus on D-dimer and its role in predicting the severity of COVID-19 has been discussed. A comprehensive search of the medical literature on PubMed was done till May 30th, 2020 with the keywords 'COVID-19', 'SARS-CoV-2', 'Coronavirus', 'Coagulopathy', and 'D-dimer'. Twenty-two studies were taken for weighted pooled analysis of D-dimer. EXPERT OPINION: A tailored anticoagulant regimen, including intensification of standard prophylactic regimens with low-molecular-weight heparin is advisable for COVID-19 patients. Atypical manifestations and varying D-dimer levels seen in different populations bring forth the futility of uniform recommendations for anticoagulant therapy. Further, direct thrombin inhibitors and platelet inhibitors in a patient-specific manner should also be considered.

The impact of the definition of preeclampsia on disease diagnosis and outcomes: a retrospective cohort study.

BACKGROUND: The diagnostic criteria for preeclampsia have evolved from the traditional definition of de novo hypertension and proteinuria to a broader definition of hypertension with evidence of end-organ dysfunction. Although this change is endorsed by various societies such as the International Society for the Study of Hypertension in Pregnancy and the American College of Obstetricians and Gynecologists, there remains controversy with regard to the implementation of broader definitions and the most appropriate definition of end-organ dysfunction. OBJECTIVE: This study aimed to assess the impact of different diagnostic criteria for preeclampsia on rates of disease diagnosis, disease severity, and adverse outcomes and to identify associations between each component of the different diagnostic criteria and adverse pregnancy outcomes. STUDY DESIGN: We performed a retrospective cohort study of singleton pregnancies at Monash Health between January 1, 2016 and July 31, 2018. Within this population, all cases of gestational hypertension and preeclampsia were reclassified according to the International Society for the Study of Hypertension in Pregnancy 2001, American College of Obstetricians and Gynecologists 2018, and International Society for the Study of Hypertension in Pregnancy 2018 criteria. Differences in incidence of preeclampsia and maternal and perinatal outcomes were compared between the International Society for the Study of Hypertension in Pregnancy 2001 group and the extra cases identified by American College of Obstetricians and Gynecologists 2018 and International Society for the Study of Hypertension in Pregnancy 2018. Outcomes assessed included biochemical markers of preeclampsia, a composite of adverse maternal outcomes, and a composite of adverse perinatal outcomes. Multiple logistic regression analysis was also performed to assess each component of the American College of Obstetricians and Gynecologists 2018 and International Society for the Study of Hypertension in Pregnancy 2018 criteria and their associations with adverse maternal and perinatal outcomes. RESULTS: Of 22,094 pregnancies, 751 (3.4%) women had preeclampsia as defined by any of the 3 criteria. Compared with International Society for the Study of Hypertension in Pregnancy 2001, the American College of Obstetricians and Gynecologists 2018 criteria identified an extra 42 women (n=654 vs n=696, 6.4% relative increase) with preeclampsia, and International Society for the Study of Hypertension in Pregnancy 2018 identified an extra 97 women (n=654 vs n=751, 14.8% relative increase). The additional women identified by International Society for the Study of Hypertension in Pregnancy 2018 exhibited a milder form of disease with lower rates of severe hypertension (62.4% vs 44.3%; P<.01) and magnesium sulfate use (11.9% vs 4.1%; P<.05) and a trend toward lower rates of adverse maternal outcomes (9.8% vs 4.1%). These women also delivered at a later gestation, and their babies had a lower number of neonatal intensive care unit admissions and adverse perinatal outcomes. Objective features such as fetal growth restriction, thrombocytopenia, renal and liver impairment, and proteinuria were associated with an increased risk of adverse maternal and perinatal outcomes, whereas subjective neurologic features demonstrated poorer associations. CONCLUSION: Implementation of broader definitions of preeclampsia will result in an increased incidence of disease diagnosis. However, because women who exclusively fulfill the new criteria have a milder phenotype of the disease, it remains uncertain whether this will translate to improved outcomes.

COVID-19-associated coagulopathy and disseminated intravascular coagulation.

The pathology of coronavirus disease 2019 (COVID-19) is exacerbated by the progression of thrombosis, and disseminated intravascular coagulation (DIC), and cytokine storms. The most frequently reported coagulation/fibrinolytic abnormality in COVID-19 is the increase in D-dimer, and its relationship with prognosis has been discussed. However, limits exist to the utility of evaluation by D-dimer alone. In addition, since the coagulation/fibrinolytic condition sometimes fluctuates within a short period of time, regular examinations in recognition of the significance of the examination are desirable. The pathophysiology of disseminated intravascular coagulation (DIC) associated with COVID-19 is very different from that of septic DIC, and both thrombotic and hemorrhagic pathologies should be noted. COVID-19 thrombosis includes macro- and microthrombosis, with diagnosis of the latter depending on markers of coagulation and fibrinolysis. Treatment of COVID-19 is classified into antiviral treatment, cytokine storm treatment, and thrombosis treatment. Rather than providing uniform treatment, the treatment method most suitable for the severity and stage should be selected. Combination therapy with heparin and nafamostat is expected to develop in the future. Fibrinolytic therapy and adsorption therapy require further study.

Coagulopathy in COVID-19 and Its Implication for Safe and Efficacious Thromboprophylaxis.

The novel coronavirus, SARS-CoV-2, is causing a global pandemic of life-threatening multiorgan disease, called COVID-19. Accumulating evidence indicates that patients with COVID-19 are at significant risk of thromboembolic complications, mainly affecting the venous, but also the arterial vascular system. While the risk of venous thromboembolism (VTE) appears to be higher in patients requiring intensive care unit support compared to those admitted to general wards, recent autopsy findings and data on the timing of VTE diagnosis relative to hospitalization clearly suggest that thromboembolic events also contribute to morbidity and mortality in the ambulatory setting. In addition to a severe hypercoagulable state caused by systemic inflammation and viral endotheliitis, some patients with advanced COVID-19 may develop a coagulopathy, which meets established laboratory criteria for disseminated intravascular coagulation, but is not typically associated with relevant bleeding. Similar to other medical societies, the Society of Thrombosis and Haemostasis Research has issued empirical recommendations on initiation, dosing, and duration of pharmacological VTE prophylaxis in COVID-19 patients.

Diabetes and severity of COVID-19: What is the link?

In Diabetes Mellitus the loss of capacity to regulate immunity, the reduction of pulmonary functions and the pro-thrombotic state determine the severity of COVID-19.

COVID-19: A Global Threat to the Nervous System.

In less than 6 months, the severe acute respiratory syndrome-coronavirus type 2 (SARS-CoV-2) has spread worldwide infecting nearly 6 million people and killing over 350,000. Initially thought to be restricted to the respiratory system, we now understand that coronavirus disease 2019 (COVID-19) also involves multiple other organs, including the central and peripheral nervous system. The number of recognized neurologic manifestations of SARS-CoV-2 infection is rapidly accumulating. These may result from a variety of mechanisms, including virus-induced hyperinflammatory and hypercoagulable states, direct virus infection of the central nervous system (CNS), and postinfectious immune mediated processes. Example of COVID-19 CNS disease include encephalopathy, encephalitis, acute disseminated encephalomyelitis, meningitis, ischemic and hemorrhagic stroke, venous sinus thrombosis, and endothelialitis. In the peripheral nervous system, COVID-19 is associated with dysfunction of smell and taste, muscle injury, the Guillain-Barre syndrome, and its variants. Due to its worldwide distribution and multifactorial pathogenic mechanisms, COVID-19 poses a global threat to the entire nervous system. Although our understanding of SARS-CoV-2 neuropathogenesis is still incomplete and our knowledge is evolving rapidly, we hope that this review will provide a useful framework and help neurologists in understanding the many neurologic facets of COVID-19. ANN NEUROL 2020;88:1-11 ANN NEUROL 2020;88:1-11.

Novel Treatment Strategy for Patients with Venom-Induced Consumptive Coagulopathy from a Pit Viper Bite.

Pit viper venom commonly causes venom-induced consumptive coagulopathy (VICC), which can be complicated by life-threatening hemorrhage. VICC has a complex pathophysiology affecting multiple steps of the coagulation pathway. Early detection of VICC is challenging because conventional blood tests such as prothrombin time (PT) and activated partial thromboplastin time (aPTT) are unreliable for early-stage monitoring of VICC progress. As the effects on the coagulation cascade may differ, even in the same species, the traditional coagulation pathways cannot fully explain the mechanisms involved in VICC or may be too slow to have any clinical utility. Antivenom should be promptly administered to neutralize the lethal toxins, although its efficacy remains controversial. Transfusion, including fresh frozen plasma, cryoprecipitate, and specific clotting factors, has also been performed in patients with bleeding. The effectiveness of viscoelastic monitoring in the treatment of VICC remains poorly understood. The development of VICC can be clarified using thromboelastography (TEG), which shows the procoagulant and anticoagulant effects of snake venom. Therefore, we believe that TEG may be able to be used to guide hemostatic resuscitation in victims of VICC. Here, we aim to discuss the advantages of TEG by comparing it with traditional coagulation tests and propose potential treatment options for VICC.