fibrin and Sepsis

The human contact system consists of plasma proteins, which - after contact to foreign surfaces - are bound to them, thereby activating the zymogens of the system into enzymes. This activation mechanism gave the system its name - contact system. It is considered as a procoagulant and proinflammatory response mechanism, as activation finally leads to the generation of fibrin and bradykinin. To date, no physiological processes have been described that are mediated by contact activation. However, contact system factors play a pathophysiological role in numerous diseases, such as cardiovascular diseases, arthritis, colitis, sepsis, and cancer. Contact system factors are therefore an interesting target for new therapeutic options in different clinical conditions.

Topics: Animals; Blood Proteins; Bradykinin; Cardiovascular Diseases; Fibrin; Humans; Inflammation; Neoplasms; Sepsis

The COVID-19 pandemic has become an urgent issue in every country. Based on recent reports, the most severely ill patients present with coagulopathy, and disseminated intravascular coagulation (DIC)-like massive intravascular clot formation is frequently seen in this cohort. Therefore, coagulation tests may be considered useful to discriminate severe cases of COVID-19. The clinical presentation of COVID-19-associated coagulopathy is organ dysfunction primarily, whereas hemorrhagic events are less frequent. Changes in hemostatic biomarkers represented by increase in D-dimer and fibrin/fibrinogen degradation products indicate the essence of coagulopathy is massive fibrin formation. In comparison with bacterial-sepsis-associated coagulopathy/DIC, prolongation of prothrombin time, and activated partial thromboplastin time, and decrease in antithrombin activity is less frequent and thrombocytopenia is relatively uncommon in COVID-19. The mechanisms of the coagulopathy are not fully elucidated, however. It is speculated that the dysregulated immune responses orchestrated by inflammatory cytokines, lymphocyte cell death, hypoxia, and endothelial damage are involved. Bleeding tendency is uncommon, but the incidence of thrombosis in COVID-19 and the adequacy of current recommendations regarding standard venous thromboembolic dosing are uncertain.

Topics: Anticoagulants; Blood Coagulation; Blood Coagulation Disorders; Blood Coagulation Tests; COVID-19; Cytokines; Disseminated Intravascular Coagulation; Fibrin; Fibrin Fibrinogen Degradation Products; Fibrinogen; Fibrinolysis; Hemorrhage; Hemostasis; Humans; Inflammation; Lung; Lymphocytes; Partial Thromboplastin Time; Protease Inhibitors; Prothrombin Time; Sepsis; Thrombosis

Topics: Animals; Bacterial Infections; Cecum; Colon; Disease Models, Animal; Fibrin; Ligation; Lipopolysaccharides; Mice; Pneumonia; Sepsis; Stents

Activation of the plasma contact system triggers several cascade systems such as the kallikrein-kinin system, the intrinsic pathway of coagulation, the classical complement cascade and the fibrinolytic system. Recent studies have shown a critical role of the contact system for arterial and venous thrombus formation and thromboembolic disease. In contrast, the function of the contact system for host-defense reactions and its physiological functions have remained enigmatic. Experimental animal studies and clinical data have linked the contact system to bacterial infections with implications for sepsis disease. The present review summarizes the role of the contact system and its activation for bacterial infections.

Topics: Animals; Bacteria; Bacterial Infections; Blood Coagulation; Capillary Permeability; Complement Pathway, Classical; Fibrin; Fibrinolysis; Humans; Immunity, Innate; Kallikrein-Kinin System; Sepsis; Signal Transduction

Inflammation and coagulation are two main host-defence systems that interact with each other. Inflammation activates coagulation and coagulation modulates the inflammatory activity in many ways. The contributing molecular pathways are reviewed. Thrombin and activated protein C (APC) and its receptor EPCR constitute a major physiological regulatory system to control vascular wall permeability during sepsis. Pro-inflammatory cellular effects of coagulation proteases as well as the anti-inflammatory effects of APC/EPCR are mediated by signaling via protease activated receptors PAR on mononuclear cells, endothelial cells, platelets, fibroblast, and smooth muscle cells. The beneficial effects of APC in sepsis are mainly dependent on the PAR-mediated cell-protective properties rather than the anticoagulant protease function on coagulation cofactors FV/Va and FVIII/VIIIa. Animal experiments with signaling selective APC-variants show promise in improving the therapeutic efficacy and safety of APC in sepsis.

Topics: Animals; Antithrombins; Blood Coagulation; Fibrin; Humans; Inflammation; Inflammation Mediators; Protein C; Receptors, Proteinase-Activated; Sepsis

Sepsis is a complex multifaceted response to a local infectious insult. One important facet is the circulatory system dysfunction, which includes capillary bed plugging. This review addresses the mechanisms of capillary plugging and highlights our recent discoveries on the roles of NO, ROS, and activated coagulation in platelet adhesion and blood flow stoppage in septic mouse capillaries. We show that sepsis increases platelet adhesion, fibrin deposition and flow stoppage in capillaries, and that NADPH oxidase-derived ROS, rather than NO, play a detrimental role in this adhesion/stoppage. P-selectin and activated coagulation are required for adhesion/stoppage. Further, platelet adhesion in capillaries (i) strongly predicts capillary flow stoppage, and (ii) may explain why severe sepsis is associated with a drop in platelet count in systemic blood. Significantly, we also show that a single bolus of the antioxidant ascorbate (injected intravenously at clinically relevant dose of 10 mg/kg) inhibits adhesion/stoppage. Our data suggest that eNOS-derived NO at the platelet-endothelial interface is anti-adhesive and required for the inhibitory effect of ascorbate. Because of the critical role of ROS in capillary plugging, ascorbate bolus administration may be beneficial to septic patients whose survival depends on restoring microvascular perfusion.

Topics: Animals; Ascorbic Acid; Blood Coagulation; Blood Flow Velocity; Blood Platelets; Capillaries; Fibrin; Humans; Mice; Models, Biological; Nitric Oxide; Oxidative Stress; Platelet Adhesiveness; Reactive Oxygen Species; Sepsis

Intravascular and extravascular fibrin formation are characteristic findings in patients with sepsis, suggesting that the activation of coagulation and the inhibiton of fibrinolysis are important in the pathogenesis of sepsis. Activation of coagulation during sepsis is primarily driven by the tissue factor (TF) pathway, while inhibition of fibrinolysis is primarily due to increases in plasminogen activator inhibitor -1(PAI-1). Downregulation of the anticoagulant Protein C pathway also plays an important role in the modulation of coagulation and inflammation in sepsis. Recent advances in the understanding of pathogenetic mechanisms of coagulation and fibrinolysis in sepsis may have therapeutic implications. Recombinant human activated protein C (rhAPC) is currently the only pharmacologic therapy that has been shown to reduce mortality in adults with severe sepsis, highlighting the importance of coagulation and fibrinolysis as a therapeutic target in sepsis. This review summarizes recent basic and clinical findings with regard to the role of the coagulation cascade in sepsis and explores potential therapeutic targets in the coagulation and fibrinolytic pathways in the management of sepsis.

Topics: Animals; Blood Coagulation; Drug Delivery Systems; Fibrin; Fibrinolysis; Humans; Plasminogen Activator Inhibitor 1; Protein C; Recombinant Proteins; Sepsis; Thromboplastin

Tissue factor plays an essential role in the initiation of coagulation in vivo. In severe conditions, including sepsis and acute lung injury, increased expression of tissue factor may induce disseminated intravascular coagulation and fibrin deposition in organs, which are believed to have a determining impact on patient outcome. Tissue factor also acts as a signaling receptor and is involved in the systemic inflammatory response, as in cancer progression and atherosclerosis. Interventions aiming at limiting tissue factor activities have been evaluated in multiple experimental studies and the observed results have supported the potential benefits for coagulation disorders, inflammation, and survival. The effects of the main physiological inhibitor of tissue factor, tissue factor pathway inhibitor, have been evaluated in two large clinical trials in sepsis. Even though they are not associated with an improved outcome, the observed data support further clinical studies.

Topics: Animals; Blood Coagulation; Clinical Trials as Topic; Disease Models, Animal; Disseminated Intravascular Coagulation; Fibrin; Humans; Inflammation; Lipoproteins; Lung; Lung Injury; Sepsis; Signal Transduction; Thromboplastin

Inhibition of the tissue factor-factor VIIa complex reduces coagulation and inflammation in animal models of endotoxemia and sepsis and in patients with severe sepsis. However, the mechanism by which tissue factor-dependent activation of the coagulation cascade enhances inflammation is not known. We tested the hypothesis that coagulation proteases enhance inflammation during endotoxemia by activating protease-activated receptors (PARs) within the vasculature. We found that genetically modified mice expressing low levels of tissue factor exhibited reduced interleukin-6 expression and increased survival in a mouse model of endotoxemia compared with control mice. In contrast, hirudin inhibition of thrombin or a deficiency in either PAR-1 or PAR-2 did not affect interleukin-6 expression or mortality. However, combining hirudin treatment to inhibit thrombin signaling through PAR-1 and PAR-4 with PAR-2 deficiency reduced lipopolysaccharide-induced interleukin-6 expression and increased survival. Taken together, our results suggest that activation of multiple PARs by coagulation proteases enhances inflammation during endotoxemia.

Topics: Animals; Anticoagulants; Blood Coagulation; Endopeptidases; Endotoxemia; Fibrin; Humans; Protein C; Receptors, Proteinase-Activated; Sepsis; Thrombin; Thromboplastin

The transmembrane glycoprotein tissue factor (TF) is the initiator of the coagulation cascade in vivo. When TF is exposed to blood, it forms a high-affinity complex with the coagulation factors factor VII/activated factor VIIa (FVII/VIIa), activating factor IX and factor X, and ultimately leading to the formation of an insoluble fibrin clot. TF plays an essential role in hemostasis by restraining hemorrhage after vessel wall injury. An overview of biological and physiological aspects of TF, covering aspects consequential for thrombosis and hemostasis such as TF cell biology and biochemistry, blood-borne (circulating) TF, TF associated with microparticles, TF encryption-decryption, and regulation of TF activity and expression is presented. However, the emerging role of TF in the pathogenesis of diseases such as sepsis, atherosclerosis, certain cancers and diseases characterized by pathological fibrin deposition such as disseminated intravascular coagulation and thrombosis, has directed attention to the development of novel inhibitors of tissue factor for use as antithrombotic drugs. The main advantage of inhibitors of the TF*FVIIa pathway is that such inhibitors have the potential of inhibiting the coagulation cascade at its earliest stage. Thus, such therapeutics exert minimal disturbance of systemic hemostasis since they act locally at the site of vascular injury.

Topics: Animals; Arteriosclerosis; Blood Coagulation; Blood Coagulation Disorders; Blood Coagulation Factors; Blood Vessels; Disseminated Intravascular Coagulation; Fibrin; Gene Expression Regulation; Humans; Neoplasms; Sepsis; Thromboplastin; Thrombosis

To review the dual characteristics of disseminated intravascular coagulation (DIC), as both a contributor to multiple organ failure as well as a symptom of severe underlying disease associated with systemic vascular changes.. Published literature data and unpublished results from the authors.. Clinical and experimental studies strongly suggest that DIC contributes to multiple organ failure and death in patients with severe systemic disorders such as sepsis. DIC is evoked by systemic cytokine activity, and the inflammatory response aggravates vascular permeability, inflammation, and cell damage in tissues. In addition to intravascular fibrin formation, thrombin and fibrin generation in tissues is also an important aspect of DIC. An example of DIC at the organ level is adult respiratory distress syndrome, where fibrin in the lung is a characteristic feature. Intravascular fibrin formation and occlusion may elicit a hypoxic response with induction of hypoxia related transcription factors. The resulting ischemic preconditioning may offer protective effects to the involved organ(s).. Overall, the beneficial or harmful effects of activated coagulation and fibrin formation for organ pathology and recovery from DIC remain to be explored. This may be a critical element in the assessment of ischemia-reperfusion effects of specific anticoagulant therapy.

Topics: Anticoagulants; Capillary Permeability; Cytokines; Disseminated Intravascular Coagulation; Endothelium, Vascular; Fibrin; Humans; Inflammation; Microcirculation; Multiple Organ Failure; Respiratory Distress Syndrome; Sepsis; Thrombin

Topics: Animals; Disease Models, Animal; Disease Progression; Drug Evaluation, Preclinical; Fibrin; Fibrinolysis; Humans; Lipoproteins; Multiple Organ Failure; Protein C; Respiratory Distress Syndrome; Sepsis; Treatment Outcome

Topics: Animals; Anticoagulants; Bacteria; Bacterial Infections; Blood Coagulation; Blood Coagulation Factor Inhibitors; Blood Coagulation Factors; Fibrin; Fibrinogen; Fibrinolysis; Hemostasis; Humans; Sepsis; Shock, Septic

Abscess formation has been viewed as a host defense strategy to contain the spread of infection. However, abscesses are also serious and life-threatening manifestations of persisting microbial infection. The initiation of abscess formation, both clinically and experimentally, involves the release of bacteria and an abscess-potentiating agent (e.g., fecal fiber or an analog) into a sterile site, with host defense mechanisms being unable to eliminate the infecting organisms. Abscess formation is aided by a combination of factors that share a common feature: impairment of phagocytic killing and hence clearance of microorganisms. These include bacterial virulence factors (e.g., capsule formation, succinic acid production); complement activation by the abscess potentiating agent; fibrin deposition; and microbial sequestration within abscess neutrophils. Recruitment of cells into the peritoneal cavity follows mast cell activation in the pathogenesis of infection: histamine and tumor necrosis factor alpha can be detected in the peritoneal cavity within minutes of challenge with an abscess-inducing mixture. However, the role of mast cells in host defense is made less clear by the finding of diminished abscess formation (but no mortality or increased morbidity) in mast-cell-depleted mice. This may indicate that mast cell products have a role in not only the initiation of an inflammatory response but also the promotion of fibrin deposition and abscess formation.

Topics: Abdominal Abscess; Animals; Disease Models, Animal; Fibrin; Humans; Inflammation; Mast Cells; Mice; Sepsis; Time Factors

Topics: Blood Platelets; Complement Activation; Endothelium; Fibrin; Humans; Lung; Multiple Organ Failure; Neutrophils; Respiratory Distress Syndrome; Sepsis; Shock, Traumatic

Septic pulmonary injury remains a significant cause of morbidity and mortality among hospitalized patients today and is likely to increase in prevalence as advances in medical technology allow the salvage of more critically ill and immunocompromised hosts. Treatment of the host's underlying disease and even of the infection itself has appeared to redeem septic patients only to have them succumb in increasing numbers to the pulmonary injury reaction. Our understanding of the mechanisms and mediators of lung dysfunction in sepsis is in a rapidly expanding phase. Currently we recognize the contributions of several blood elements, lipids, and peptides to pulmonary injury, although the relative importance and points of interaction and interdependence of these mediators remain to be established. It is hoped that a more complete understanding of the process of pulmonary injury in sepsis will suggest effective means of intervention at a stage in which damage may be reversed or minimized.

Topics: Animals; Cell Aggregation; Complement System Proteins; Fibrin; Humans; Leukotriene B4; Lung; Neutrophils; Platelet Aggregation; Prostaglandins; Respiratory Distress Syndrome; Sepsis; SRS-A

Topics: Arthritis, Rheumatoid; Binding Sites; Cell Transformation, Neoplastic; Collagen; Disseminated Intravascular Coagulation; Fibrin; Fibronectins; Humans; Molecular Weight; Opsonin Proteins; Sepsis; Surgical Procedures, Operative; Wounds and Injuries

Tissue factor is an ubiquitous phospholipid-protein complex, which triggers blood coagulation through the so-called extrinsic pathway. Reactions initiated by tissue factor bypass many of the early stages of coagulation (contact phase) and involve factors VII, X, V, II and fibrinogen but also factor IX (and VIII) as it was recently demonstrated. So, it appears that tissue factor has a key-role in the haemostasic process as it has been suggested by the mildness or the absence of haemorrhagic syndrome in contact factors deficiencies. Tissue factor activity has been found in many types of cells, especially in white bloods cells. Experimental studies have demonstrated the presence of tissue factor activity in polymorphonuclears, lymphocytes, monocytes (or macrophages). This activity is enhanced by gram-negative endotoxin stimulation, inflammation, cell mediated immunologic phenomena or malignancy. These data are in good agreement with a wild range of features observed in human pathology: fibrin deposits in inflammatory lesions, disseminated intravascular coagulation (DIC) during the course of gram-negative septicemias or acute promyelocytic leukemias, local thrombi at the early phase of graft rejection. The protective effect of a phospholipase C against DIC induced in rats by tissue factor infusion suggests in the future, a specific therapy would be possible in man that, in the frequent clinical conditions involving clotting activation through tissue factor pathway.

Topics: Animals; Blood Coagulation; Blood Coagulation Factors; Disseminated Intravascular Coagulation; Fibrin; Graft Rejection; Humans; Inflammation; Leukemia; Leukocytes; Rabbits; Sepsis; Thromboplastin

Defibrination is a fairly common clinical entity seen in a wide variety of clinical disorders. With an awareness of the likely clinical settings, a high degree of suspicion, and widely available sensitive laboratory tests, the diagnosis is ordinarily easily made. The best therapy is usually that which is directed at the underlying disease rather than at the defibrination syndrome itself. In certain symptomatic cases, heparin and/or replacement therapy is indicated, especially if the underlying disorder cannot be immediately successfully treated. On occasion, antifibrinolytic therapy will be useful, always with due regard to the danger of renal cortical necrosis. Depending on the clinical setting, it may be advisable to give heparin with the antifibrinolytic therapy to minimize that danger.

Topics: Adult; Aged; Antifibrinolytic Agents; Blood Cell Count; Blood Coagulation Factors; Disseminated Intravascular Coagulation; Female; Fetal Death; Fibrin; Fibrin Fibrinogen Degradation Products; Fibrinolysis; Heparin; Humans; Male; Postoperative Complications; Pregnancy; Prostatic Neoplasms; Sepsis; Syndrome

Topics: Animals; Antibodies, Bacterial; Bacteria; Blood Platelets; Coronary Disease; Endocarditis; Endocarditis, Bacterial; Endocarditis, Subacute Bacterial; Fibrin; Heart Failure; Heart Valves; Humans; Platelet Aggregation; Prognosis; Rupture, Spontaneous; Sepsis; Thrombosis

Topics: Abruptio Placentae; Blood Coagulation; Blood Coagulation Disorders; Blood Coagulation Factors; Blood Coagulation Tests; Blood Platelet Disorders; Blood Transfusion; Disseminated Intravascular Coagulation; Embolism, Amniotic Fluid; Factor XIII Deficiency; Female; Fetal Death; Fetal Diseases; Fibrin; Fibrinogen; Fibrinolysis; Hemophilia A; Humans; Liver Diseases; Pre-Eclampsia; Pregnancy; Pregnancy Complications, Hematologic; Sepsis; Uterine Hemorrhage; Vitamin K

Topics: Adolescent; Adrenal Glands; Adult; Aged; Blood Coagulation Disorders; Child; Female; Fibrin; Hemorrhagic Disorders; Heparin; Humans; Kidney; Male; Meningitis; Middle Aged; Pneumococcal Infections; Sepsis; Splenectomy; Splenic Diseases; Thrombosis; Waterhouse-Friderichsen Syndrome

The opportunistic pathogen Pseudomonas aeruginosa causes a wide range of infections in multiple hosts by releasing an arsenal of virulence factors such as pyocyanin. Despite numerous reports on the pleiotropic cellular targets of pyocyanin toxicity in vivo, its impact on erythrocytes remains elusive. Erythrocytes undergo an apoptosis-like cell death called eryptosis which is characterized by cell shrinkage and phosphatidylserine (PS) externalization; this process confers a procoagulant phenotype on erythrocytes as well as fosters their phagocytosis and subsequent clearance from the circulation. Herein, we demonstrate that P. aeruginosa pyocyanin-elicited PS exposure and cell shrinkage in erythrocyte while preserving the membrane integrity. Mechanistically, exposure of erythrocytes to pyocyanin showed increased cytosolic Ca(2+) activity as well as Ca(2+) -dependent proteolytic processing of μ-calpain. Pyocyanin further up-regulated erythrocyte ceramide abundance and triggered the production of reactive oxygen species. Pyocyanin-induced increased PS externalization in erythrocytes translated into enhanced prothrombin activation and fibrin generation in plasma. As judged by carboxyfluorescein succinimidyl-ester labelling, pyocyanin-treated erythrocytes were cleared faster from the murine circulation as compared to untreated erythrocytes. Furthermore, erythrocytes incubated in plasma from patients with P. aeruginosa sepsis showed increased PS exposure as compared to erythrocytes incubated in plasma from healthy donors. In conclusion, the present study discloses the eryptosis-inducing effect of the virulence factor pyocyanin, thereby shedding light on a potentially important mechanism in the systemic complications of P. aeruginosa infection.

Topics: Adult; Aged; Aged, 80 and over; Blood Coagulation; Calcium; Calpain; Cations, Divalent; Ceramides; Eryptosis; Erythrocytes; Female; Fibrin; Humans; Ion Transport; Male; Middle Aged; Phosphatidylserines; Prothrombin; Pseudomonas aeruginosa; Pseudomonas Infections; Pyocyanine; Reactive Oxygen Species; Sepsis; Virulence Factors

PROWESS (Recombinant Human Activated Protein C Worldwide Evaluation in Severe Sepsis) was a phase III, randomized, double blind, placebo controlled, multicenter trial conducted in patients with severe sepsis from 164 medical centers. Here we report data collected at study entry for 1690 patients and over the following 7 days for the 840 patients who received placebo (in addition to usual standard of care).. Nineteen biomarkers of coagulation activation, anticoagulation, fibrinolysis, endothelial injury, and inflammation were analyzed to determine the relationships between baseline values and their change over time, with 28-day survival, and type of infecting causative micro-organism.. Levels of 13 of the 19 biomarkers at baseline correlated with Acute Physiology and Chronic Health Evaluation II scores, and nearly all patients exhibited coagulopathy, endothelial injury, and inflammation at baseline. At study entry, elevated D-dimer, thrombin-antithrombin complexes, IL-6, and prolonged prothrombin time were present in 99.7%, 95.5%, 98.5%, and 93.4% of patients, respectively. Markers of endothelial injury (soluble thrombomodulin) and deficient protein C, protein S, and antithrombin were apparent in 72%, 87.6%, 77.8%, and 81.7%, respectively. Impaired fibrinolysis (elevated plasminogen activator inhibitor-1) was observed in 44% of patients. During the first 7 days, increased prothrombin time (which is readily measurable in most clinical settings) was highly evident among patients who were not alive at 28 days.. Abnormalities in biomarkers of inflammation and coagulation were related to disease severity and mortality outcome in patients with severe sepsis. Coagulopathy and inflammation were universal host responses to infection in patients with severe sepsis, which were similar across causative micro-organism groups.

Topics: APACHE; Biomarkers; Blood Coagulation Disorders; C-Reactive Protein; Disseminated Intravascular Coagulation; Endothelium; Fibrin; Fibrinolysis; Humans; Inflammation; Partial Thromboplastin Time; Placebos; Prognosis; Protein C; Recombinant Proteins; Sensitivity and Specificity; Sepsis; Severity of Illness Index; Surgical Procedures, Operative; Surgical Wound Infection

To assess whether adding low-dose heparin to the infusate of patients receiving parenteral nutrition reduced the incidence of septic complications related to the central venous catheter, 80 consecutive patients requiring intravenous feeding were studied. Half of these patients received heparin 1 unit/ml of infusate, while in the remaining 40 (controls) an equal volume of physiological saline was added to the infusate. Strict criteria for the management of the indwelling CVC were observed. The catheter tips were cultured after removal: only one was infected in the heparin group compared with nine in the control group. This significant reduction may have been due to the heparin preventing a fibrin sleeve from forming around the catheter tip. It is recommended that, as well as observing the usual aseptic precautions in managing the cannula, 500 units of heparin are added to each 500 ml of fluid infused to reduce the incidence of catheter-associated sepsis.

Topics: Bacterial Infections; Catheters, Indwelling; Drug Administration Schedule; Fibrin; Heparin; Humans; Injections, Intravenous; Parenteral Nutrition; Sepsis

Sepsis is a lethal syndrome characterized by systemic inflammation and abnormal coagulation. Despite therapeutic advances, sepsis mortality remains substantially high. Herein, we investigated the role of the plasminogen/plasmin (Plg/Pla) system during sepsis. Plasma levels of Plg were significantly lower in mice subjected to severe compared with nonsevere sepsis, whereas systemic levels of IL-6, a marker of sepsis severity, were higher in severe sepsis. Plg levels correlated negatively with IL-6 in both septic mice and patients, whereas plasminogen activator inhibitor-1 levels correlated positively with IL-6. Plg deficiency render mice susceptible to nonsevere sepsis induced by cecal ligation and puncture (CLP), resulting in greater numbers of neutrophils and M1 macrophages, liver fibrin(ogen) deposition, lower efferocytosis, and increased IL-6 and neutrophil extracellular trap (NET) release associated with organ damage. Conversely, inflammatory features, fibrin(ogen), and organ damage were substantially reduced, and efferocytosis was increased by exogenous Pla given during CLP- and LPS-induced endotoxemia. Plg or Pla protected mice from sepsis-induced lethality and enhanced the protective effect of antibiotics. Mechanistically, Plg/Pla-afforded protection was associated with regulation of NET release, requiring Pla-protease activity and lysine binding sites. Plg/Pla are important host-protective players during sepsis, controlling local and systemic inflammation and collateral organ damage.

Topics: Animals; Extracellular Traps; Fibrin; Fibrinolysin; Inflammation; Interleukin-6; Mice; Plasminogen; Sepsis

Previous studies identified decreased clot permeability, without differences in fibrin fiber density in clots, from patients with cirrhosis compared with those from healthy controls (HCs). Fibrinogen hypersialylation could be the reason for this discrepancy.. The aim of this work was to study mechanical properties of clots and reassess clot permeability in relation to hypersialylation in patients with stable cirrhosis, acute decompensation, and acute-on-chronic liver failure (ACLF). Sepsis patients without liver disease were included to distinguish between liver-specific and inflammation-driven phenotypes.. Pooled plasma was used for rheology and permeability experiments. Permeability was assessed with compression using a rheometer and by liquid permeation. Purified fibrinogen treated with neuraminidase was used to study the effects of fibrinogen hypersialylation on liquid permeation.. Mechanical properties of clots from patients with stable cirrhosis and acute decompensation were similar to those of clots from HCs, but clots from patients with ACLF were softer and ruptured at lower shear stress. Clots from sepsis patients without liver disease were stiffer than those from the other groups, but this effect disappeared after adjusting for increased plasma fibrinogen concentrations. Permeability was similar between clots under compression from HCs and clots under compression from patients but decreased with increasing disease severity in liquid permeation. Removal of fibrinogen sialic acid residues increased permeability more in patients than in controls.. Clots from patients with ACLF have weak mechanical properties despite unaltered fibrin fiber density. Previous liquid permeation experiments may have erroneously concluded that clots from patients with ACLF are prothrombotic as fibrinogen hypersialylation leads to underestimation of clot permeability in this setting, presumably due to enhanced water retention.

Topics: Acute-On-Chronic Liver Failure; Fibrin; Fibrinogen; Fibrinolysis; Fibrosis; Hemostatics; Humans; Liver Cirrhosis; Sepsis; Thrombosis

Disseminated fibrin-rich microthrombi have been reported in patients who died from COVID-19. Our objective is to determine whether the fibrin clot structure and function differ between critically ill patients with or without COVID-19 and to correlate the structure with clinical coagulation biomarkers.. A cross-sectional observational study. Platelet poor plasma was used to analyze fibrin clot structure; the functional implications were determined by quantifying clot turbidity and porosity.. ICU at an academic medical center and an academic laboratory.. Patients admitted from July 1 to August 1, 2020, to the ICU with severe acute respiratory syndrome coronavirus 2 infection confirmed by reverse transcription-polymerase chain reaction or patients admitted to the ICU with sepsis.. None.. Blood was collected from 36 patients including 26 ICU patients with COVID-19 and 10 ICU patients with sepsis but without COVID-19 at a median of 11 days after ICU admission (interquartile range, 3-16). The cohorts were similar in age, gender, body mass index, comorbidities, Sequential Organ Failure Assessment (SOFA) score, and mortality. More patients with COVID-19 (100% vs 70%; p = 0.003) required anticoagulation. Ex vivo fibrin clots formed from patients with COVID-19 appeared to be denser and to have smaller pores than those from patients with sepsis but without COVID-19 (percent area of fluorescent fibrin 48.1% [SD, 16%] vs 24.9% [SD, 18.8%]; p = 0.049). The turbidity and flow-through assays corroborated these data; fibrin clots had a higher maximum turbidity in patients with COVID-19 compared with patients without COVID-19 (0.168 vs 0.089 OD units; p = 0.003), and it took longer for buffer to flow through these clots (216 vs 103 min; p = 0.003). In patients with COVID-19, d-dimer levels were positively correlated with percent area of fluorescent fibrin (ρ = 0.714, p = 0.047). Denser clots (assessed by turbidity and thromboelastography) and higher SOFA scores were independently associated with delayed clot lysis.. We found aberrant fibrin clot structure and function in critically ill patients with COVID-19. These findings may contribute to the poor outcomes observed in COVID-19 patients with widespread fibrin deposition.

Topics: COVID-19; Critical Illness; Cross-Sectional Studies; Fibrin; Fibrinolysis; Humans; Sepsis; Thromboembolism; Thrombosis

Background: Endotoxemia causes endothelial dysfunction and microthrombosis, which are pathogenic mechanisms of coagulopathy and organ failure during sepsis. Simvastatin has potential anti-thrombotic effects on liver endothelial cells. We investigated the hemostatic changes induced by lipopolysaccharide (LPS) and explored the protective effects of simvastatin against liver vascular microthrombosis. Methods and results: We compared male Wistar rats exposed to LPS (5 mg/kg one i.p. dose) or saline in two experimental protocols—placebo (vehicle) and simvastatin (25 mg/kg die, orally, for 3 days before LPS). Morphological studies were performed by light- and electron-microscopy analyses to show intravascular fibrin deposition, vascular endothelial structure and liver damage. Peripheral- and organ-hemostatic profiles were analyzed using whole blood viscoelastometry by ROTEM, liver biopsy and western-blot/immunohistochemistry of thrombomodulin (TM), as well as immunohistochemistry of the von Willebrand factor (VWF). LPS-induced fibrin deposition and liver vascular microthrombosis were combined with a loss of sinusoidal endothelial TM expression and VWF-release. These changes were associated with parenchymal eosinophilia and necrosis. ROTEM analyses displayed hypo-coagulability in the peripheral blood that correlated with the degree of intrahepatic fibrin deposition (p < 0.05). Simvastatin prevented LPS-induced fibrin deposition by preserving TM expression in sinusoidal cells and completely reverted the peripheral hypo-coagulability caused by endotoxemia. These changes were associated with a significant reduction of liver cell necrosis without any effect on eosinophilia. Conclusions: Simvastatin preserves the antithrombotic properties of sinusoidal endothelial cells disrupted by LPS, deserving pharmacological properties to contrast sepsis-associated coagulopathy and hepatic failure elicited by endotoxemia

Topics: Animals; Disease Models, Animal; Endothelial Cells; Endotoxemia; Fibrin; Hemostatics; Lipopolysaccharides; Liver Diseases; Male; Necrosis; Rats; Rats, Wistar; Sepsis; Simvastatin; Thrombosis; von Willebrand Factor

Excessive activation of the coagulation cascades leads to life-threatening disseminated intravascular coagulation (DIC) in sepsis. Two recent studies by our group and others have both demonstrated the noncanonical inflammasome is pivotal for the endotoxin or gram-negative bacterial-induced coagulation. Based on this, we further evaluated the function of the NLRP3 inflammasome, the most studied inflammasome, in endotoxin-induced coagulation.. We established an endotoxin-induced coagulation model by intraperitoneal injection of sublethal doses of LPS in mice. Mice were sacrificed 8 h after injection and blood was collected for thrombin-antithrombin (TAT), plasminogen activator inhibitor-1 (PAI-1), prothrombin time (PT), D-dimer, IL-1β and tissue factor (TF) measurements by commercial ELISA. Lungs and livers were examined via HE staining images to determine injury scores and immunohistochemistry for TF expression and fibrin deposits. The role of NLRP3 activation was evaluated in wild-type (WT), Nlrp3. Inhibition of NLRP3 by MCC950 as well as NLRP3 or ASC deficiency decreased TAT, PAI-1, PT, D-dimer, and TF levels in blood and impaired the thrombus formation and fibrin deposition, as well as declined expression of TF in the liver and lung in endotoxin-induced coagulation but not caspase-11 deficiency. Impressively, IL-1β release is increased in LPS-treated Caspase-11. The NLRP3 inflammasome contributes to endotoxin-induced coagulation by promoting TF expression at least in part through the induction of IL-1β release. These findings broadened our understanding of the mechanism of coagulation and implicated a possible therapeutic strategy for preventing coagulation in sepsis.

Topics: Animals; Caspases; Endotoxins; Fibrin; Humans; Inflammasomes; Interleukin-1beta; Lipopolysaccharides; Mice; NLR Family, Pyrin Domain-Containing 3 Protein; Plasminogen Activator Inhibitor 1; Sepsis

Implantation of bacteria embedded in a fibrin clot allows for successful establishment of sepsis in preclinical models. This model allows the investigator to modulate the strain of bacteria as well as the bacterial load delivered. As it allows for a slow release of standardized bacteria, the use of a fibrin clot model may be considered in studying the initial and later phases of sepsis and the host response to infection. Here we describe methods for performing the fibrin clot model of sepsis.

Topics: Animals; Bacteria; Disease Models, Animal; Female; Fibrin; Male; Mice; Mice, Inbred C57BL; Sepsis; Thrombosis

Topics: Blood Coagulation Disorders; Disseminated Intravascular Coagulation; Fibrin; Humans; Prothrombin Time; Sepsis

Topics: Blood Coagulation Disorders; Disseminated Intravascular Coagulation; Fibrin; Humans; Prothrombin Time; Sepsis

The histological findings in the heart in cases of fatal sepsis can show myocytolysis, interstitial fibrosis, necrotic contraction band, mononuclear infiltrates, and interstitial edema, which can be used in post mortem diagnosis of sepsis. Septic myocardial calcification is a very rare condition, and only a few cases have been reported in the literature. In general, the pathogenesis of the myocardial calcification has not been well clarified, but two pathogenic mechanisms have been universally recognized: metastatic or dystrophic. We present a rare case of sepsis-related myocardial calcification. Here we report a case involving a 72-year-old white male who was admitted to a hospital for a polytrauma caused by a motorbike accident. On the 110th day of hospitalization, the patient was diagnosed with a septic process and a subsequent transesophageal echocardiogram revealed the presence of a calcification on the right atrial wall. According to the medical history of the patient there were no systemic factors predisposing to calcium crystals deposition in tissues. Patient died due to multi-organ failure in the course of multimicrobial septic shock during the 149th day. The autopsy revealed both the presence of a greenish-brown formation and a greater consistency of the right atrial wall. The histological investigation of the right atrium wall showed a wide calcification area localized at subendocardial level, which contained fibrin deposition and was surrounded by fibrotic tissue.

Topics: Aged; Calcinosis; Fatal Outcome; Fibrin; Fibrosis; Heart Atria; Humans; Male; Multiple Organ Failure; Sepsis; Shock, Septic

The clinical benefit of second-generation drug-eluting stents (2nd DES) has been established, compared to first-generation drug-eluting stents (1st DES). However, pathological response after 2nd DES implantation remains unclear, particularly in the Japanese population.. Using specimens obtained by autopsy, we compared the histology between 2nd DES (41 sections) and 1st DES (38 sections) lesions within 1 year after stent implantation to evaluate early tissue reaction in Japanese patients. Stent segments were fixed with 10% buffered formalin and embedded in plastic, followed by hematoxylin-eosin and Masson's trichrome staining. Ratio of covered stent struts was calculated, and the area of fibrin deposition was morphometrically evaluated. The degree of inflammation around struts was examined semi-quantitatively (score 0-3).. The ratio of covered struts and mean fibrin area of 2nd DES were 0.69±0.05 and 658.0±173.4μm. Histopathological analysis showed advanced healing process in 2nd DES compared with 1st DES lesions. These results are consistent with clinical beneficial outcome of 2nd DES implantation.

Topics: Aged; Aneurysm, Ruptured; Colitis, Ischemic; Coronary Vessels; Drug-Eluting Stents; Everolimus; Female; Fibrin; Heart Failure; Humans; Inflammation; Japan; Male; Middle Aged; Neointima; Pancreatitis; Pneumonia; Renal Insufficiency; Risk Factors; Sepsis; Sirolimus; Treatment Outcome

Soluble glycoprotein VI (sGPVI) is shed from the platelet surface and is a marker of platelet activation in thrombotic conditions. We assessed sGPVI levels together with patient and clinical parameters in acute and chronic inflammatory conditions, including patients with thermal injury and inflammatory bowel disease and patients admitted to the intensive care unit (ICU) for elective cardiac surgery, trauma, acute brain injury, or prolonged ventilation. Plasma sGPVI was measured by enzyme-linked immunosorbent assay and was elevated on day 14 after thermal injury, and was higher in patients who developed sepsis. sGPVI levels were associated with sepsis, and the value for predicting sepsis was increased in combination with platelet count and Abbreviated Burn Severity Index. sGPVI levels positively correlated with levels of D-dimer (a fibrin degradation product) in ICU patients and patients with thermal injury. sGPVI levels in ICU patients at admission were significantly associated with 28- and 90-day mortality independent of platelet count. sGPVI levels in patients with thermal injury were associated with 28-day mortality at days 1, 14, and 21 when adjusting for platelet count. In both cohorts, sGPVI associations with mortality were stronger than D-dimer levels. Mechanistically, release of GPVI was triggered by exposure of platelets to polymerized fibrin, but not by engagement of G protein-coupled receptors by thrombin, adenosine 5'-diphosphate, or thromboxane mimetics. Enhanced fibrin production in these patients may therefore contribute to the observed elevated sGPVI levels. sGPVI is an important platelet-specific marker for platelet activation that predicts sepsis progression and mortality in injured patients.

Topics: Biomarkers; Burns; Disease Progression; Fibrin; Fibrin Fibrinogen Degradation Products; Humans; Inflammation; Inflammatory Bowel Diseases; Mortality; Platelet Activation; Platelet Count; Platelet Membrane Glycoproteins; Predictive Value of Tests; Sepsis; Solubility

Objective- Terminal complications of bacterial sepsis include development of disseminated intravascular consumptive coagulopathy. Bacterial constituents, including long-chain polyphosphates (polyP), have been shown to activate the contact pathway of coagulation in plasma. Recent work shows that activation of the contact pathway in flowing whole blood promotes thrombin generation and platelet activation and consumption distal to thrombus formation ex vivo and in vivo. Here, we sought to determine whether presence of long-chain polyP or bacteria in the bloodstream promotes platelet activation and consumption in a coagulation factor (F)XII-dependent manner. Approach and Results- Long-chain polyP promoted platelet P-selectin expression, microaggregate formation, and platelet consumption in flowing whole blood in a contact activation pathway-dependent manner. Moreover, long-chain polyP promoted local fibrin formation on collagen under shear flow in a FXI-dependent manner. Distal to the site of thrombus formation, platelet consumption was dramatically enhanced in the presence of long-chain polyP in the blood flow in a FXI- and FXII-dependent manner. In a murine model, long-chain polyP promoted platelet deposition and fibrin generation in lungs in a FXII-dependent manner. In a nonhuman primate model of bacterial sepsis, pre-treatment of animals with an antibody blocking FXI activation by FXIIa reduced lethal dose

Topics: Animals; Blood Coagulation; Blood Platelets; Disease Models, Animal; Factor XII; Factor XIIa; Female; Fibrin; Humans; Male; Mice, Inbred BALB C; Mice, Inbred C57BL; Mice, Knockout; Papio ursinus; Platelet Activation; Polyphosphates; Prekallikrein; Pulmonary Embolism; Sepsis; Signal Transduction; Staphylococcal Infections; Thrombosis; Tissue Kallikreins

Patients with sepsis commonly exhibit a hypercoagulability with high risk of venous thromboembolism (VTE). Neutrophil extracellular traps (NETs) are found to trigger inflammation and coagulation. We aim to determine whether NETs promoted the hypercoagulability and early anticoagulation reduced NETs releasing during sepsis.. In this prospective study, septic patients between September 2013 and June 2015 were included. Patients of age <18 years, acute organ failure, pregnancy, coagulation disorders, receiving anticoagulation before admission were excluded. Blood was sampled in 52 sepsis and 10 non-sepsis patients and 40 healthy controls, clinical, and hematological parameters were collected. The ability of plasma and platelets to prime neutrophils to release NETs and contribution of NETs to coagulation were assessed. NETs releasing was compared in patients with or without early coagulation, and its correlation with the risk of VTE was also evaluated.. NETs formation in septic patients was significantly higher than controls and non-sepsis patients. Neutrophils from septic patients had significantly enhanced NETs releasing compared with those from controls or non-sepsis patients. Plasma or platelets obtained from patients induced control neutrophils to release NETs. Notably, NETs released by neutrophils from septic patients significantly increased the potency of control plasma to generate thrombin and fibrin, and this effect was attenuated by administration of DNase I. Post-treatment NETs releasing in septic patients receiving early anticoagulation within 6 h was significantly lower than patients without early anticoagulation. The NETs formation correlated positively with the VTE risk, rather than the parameters of inflammation or disease severity.. The systemic inflammation during sepsis primes neutrophils to release NETs with increased risk of VTE. Early anticoagulation (6 h) reduces NETs releasing and may improve the coagulopathy of septic patients.

Topics: Adult; Aged; Blood Coagulation; Extracellular Traps; Female; Fibrin; Fluorescent Antibody Technique; Humans; Inflammation; Male; Middle Aged; Neutrophils; Prospective Studies; Sepsis; Thrombin; Thrombophilia

Essentials Immunity and coagulation are linked during sepsis but the role of thrombin is not fully elucidated. We investigated the effect of thrombin inhibition on murine Klebsiella pneumosepsis outcome. Thrombin is crucial for survival and limiting bacterial growth in pneumonia derived sepsis. Thrombin improves host defense via fibrin and enhancement of platelet-neutrophil interactions.. Background Innate immunity and coagulation are closely linked during sepsis. Their interaction can be detrimental to the outcome because of microvascular failure but can also enhance host defense. The role of thrombin therein has not been fully elucidated. Objective We aimed to investigate the contribution of thrombin to the host response during pneumonia-derived sepsis. Methods Mice treated with the specific thrombin inhibitor dabigatran or control chow were infected with the common human sepsis pathogen Klebsiella (K.) pneumoniae via the airways. In subsequent infection experiments, mice were additionally treated with ancrod to deplete fibrinogen. Ex vivo Klebsiella growth was assessed by incubating human whole blood or specific blood components in various conditions with Klebsiella. Results Thrombin inhibition by dabigatran enhanced bacterial outgrowth and spreading, and accelerated mortality. Thrombin inhibition did not influence neutrophil recruitment to the lung or activation or neutrophil extracellular trap formation. Dabigatran reduced D-dimer formation and fibrin deposition in the lung. Fibrin depletion also enhanced bacterial outgrowth and spreading, and thrombin inhibition had no additional effect. Both thrombin and fibrin polymerization inhibited ex vivo Klebsiella outgrowth in human whole blood, which was neutrophil dependent, and the effect of thrombin required the presence of platelets and platelet protease activated receptor-1. In vivo thrombin inhibition reduced platelet-neutrophil complex formation and endothelial cell activation, but did not prevent sepsis-induced thrombocytopenia or organ damage. Conclusions These results suggest that thrombin plays an important role in protective immunity during pneumonia-derived sepsis by fibrin polymerization and enhancement of platelet-neutrophil interactions.

Topics: Animals; Blood Coagulation; Blood Platelets; Cell Communication; Dabigatran; Extracellular Traps; Female; Fibrin; Fibrinogen; Flow Cytometry; Humans; Immune System; Immunity, Innate; Klebsiella Infections; Klebsiella pneumoniae; Lung; Mice; Mice, Inbred C57BL; Microcirculation; Neutrophils; Pneumonia, Bacterial; Sepsis; Thrombin

Neutrophil extracellular traps (NETs) composed primarily of DNA and histones are a link between infection, inflammation and coagulation. NETs promote coagulation and approaches to destabilise NETs have been explored to reduce thrombosis and treat sepsis. Heparinoids bind histones and we report quantitative studies in plasma and purified systems to better understand physiological consequences. Unfractionated heparin (UFH) was investigated by activated partial thromboplastin time (APTT) and alongside low-molecular-weight heparins (LMWH) in purified systems with thrombin or factor Xa (FXa) and antithrombin (AT) to measure the sensitivity of UFH or LMWH to histones. A method was developed to assess the effectiveness of DNA and non-anticoagulant heparinoids as anti-histones. Histones effectively neutralised UFH, the IC50 value for neutralisation of 0.2 IU/ml UFH was 1.8 µg/ml histones in APTT and 4.6 µg/ml against 0.6 IU/ml UFH in a purified system. Histones also inhibited the activities of LMWHs with thrombin (IC50 6.1 and 11.0 µg/ml histones, for different LMWHs) or FXa (IC50 7.8 and 7.0 µg/ml histones). Direct interactions of UFH and LMWH with DNA and histones were explored by surface plasmon resonance, while rheology studies showed complex effects of histones, UFH and LMWH on clot resilience. A conclusion from these studies is that anticoagulation by UFH and LMWH will be compromised by high affinity binding to circulating histones even in the presence of DNA. A complete understanding of the effects of histones, DNA and heparins on the haemostatic system must include an appreciation of direct effects on fibrin and clot structure.

Topics: Anticoagulants; Antithrombins; Blood Coagulation; Coagulants; DNA; Elasticity; Fibrin; Hemostasis; Heparin; Heparin, Low-Molecular-Weight; Histones; Humans; Inhibitory Concentration 50; Partial Thromboplastin Time; Plasma; Protein Binding; Sepsis; Surface Plasmon Resonance; Thrombosis; Viscosity

Fibrin degradation results in the formation of fibrin degradation products (FDPs) of different molecular weights, which include D-dimer. Commercial D-dimer assays recognize multiple forms of FDP with different specificity. As a result, the absence of an international D-dimer standard and the marked discrepancy in the D-dimer values in the same samples measured by assays from different manufacturers have become the primary problems that clinicians face in the D-dimer determination. We consider that an assay with equal specificity to all FDP forms regardless of their molecular weights could help to solve these problems. We aimed to produce mAbs that could equally recognize high-molecular-weight FDP (HMW FDP) and D-dimer. mAbs against D-dimer were produced. The HMW FDP/D-dimer ratios in plasma samples were analyzed following protein separation by gel filtration using the developed fluoroimmunoassay. A sandwich immunoassay with equal specificity to HMW FDP and D-dimer was developed and applied to determine HMW FDP/D-dimer ratios in patients with different diseases. Although the HMW FDP levels prevailed in thrombotic patients, the FDP and D-dimer levels were comparable in septic patients. Meanwhile, the D-dimer levels often exceeded the HMW FDP levels in patients who had undergone surgery. The 'D-dimer' levels that were detected by different assays also varied greatly depending on the assay specificities to FDP and D-dimer. Our findings show that the introduction of assays with equal specificities to FDP and D-dimer in clinical practice is a possible way of standardizing D-dimer measurements.

Topics: Abdominal Cavity; Animals; Antibodies, Monoclonal; Antibody Specificity; Fibrin; Fibrin Fibrinogen Degradation Products; Fibrinolysis; Humans; Hybridomas; Immunoassay; Mice; Mice, Inbred BALB C; Molecular Weight; Reagent Kits, Diagnostic; Sepsis; Spleen; Venous Thrombosis

The thrombin generation test (TGT) describes the ability of the plasma to generate thrombin. Its usefulness in septic patients has yet to be assessed.. Patients admitted for severe sepsis in a medical intensive care unit were sampled for TGT on day 0, 3, 6, and 10. TGT data were compared to "classical" hemostastic tests and to outcome parameters, notably disseminated intravascular coagulation (DIC) according to International Society for Thrombosis and Hemostasis criteria as well as survival.. A total of 102 patients were recruited of whom 11 received therapeutic anticoagulation and showed profoundly-altered TGT parameters. In comparison to healthy subjects, the 67 septic patients without DIC exhibited longer Lag times, higher Rate Indices, no change in peak or amount of thrombin generated, although the return to baseline was prolonged. In the 24 DIC patients, Lag time and Rate Index did not differ from healthy subjects (Rate Index being significantly lower than in Sepsis patients). The decreases in peak and amount of thrombin generated were not significant. Return to baseline was prolonged comparatively to Sepsis patients. Due to a large overlap of TGT values between groups, the ability of TGT parameters to diagnose DIC or predict survival was respectively poor or absent.. The thrombin Generation Test displayed particular patterns in septic patients and in septic DIC patients. The wide overlap between patients in TGT values prevents the usefulness of this test in clinical practice.

Topics: Aged; Blood Coagulation; Blood Coagulation Tests; Critical Care; Disseminated Intravascular Coagulation; Female; Fibrin; Hemostasis; Humans; Male; Middle Aged; Prospective Studies; Sepsis; Thrombin; Time Factors

Carboxypeptidase B2 (CPB2) is a basic carboxypeptidase with fibrin and complement C3a and C5a as physiological substrates. We hypothesized that in polymicrobial sepsis, CPB2-deficient mice would have sustained C5a activity, leading to disease exacerbation.. Polymicrobial sepsis was induced by cecal ligation and puncture (CLP).. Contrary to our hypothesis, Cpb2(-/-) mice had significantly improved survival, with reduced lung edema, less liver and kidney damage, and less disseminated intravascular coagulation. Hepatic pro-CPB2 was induced by CLP, leading to increased pro-CPB2 levels. Thrombomodulin present on mesothelium supported thrombin activation of pro-CPB2. Both wild-type and Cpb2(-/-) animals treated with a C5a receptor antagonist had improved survival, demonstrating that C5a was detrimental in this model. Treatment with a fibrinolysis inhibitor, tranexamic acid, caused a decrease in survival in both genotypes; however, the Cpb2(-/-) animals retained their survival advantage. Administration of a C3a receptor antagonist exacerbated the disease in both wild-type and Cpb2(-/-) mice and eliminated the survival advantage of Cpb2(-/-) mice. C5a receptor is expressed in both peritoneal macrophages and neutrophils; in contrast, C3a receptor expression is restricted to peritoneal macrophages, and C3a induced signaling in macrophages but not neutrophils.. While C5a exacerbates the peritonitis, resulting in a deleterious generalized inflammatory state, C3a activation of peritoneal macrophages may limit the initial infection following CLP, thereby playing a diametrically opposing protective role in this polymicrobial sepsis model.

Topics: Animals; Antifibrinolytic Agents; Blood Coagulation Disorders; Carboxypeptidase B2; Cecum; Cells, Cultured; Complement C3a; Complement C5a; Disease Models, Animal; Enzyme Activation; Fibrin; Inflammation Mediators; Leukopenia; Ligation; Liver; Macrophage Activation; Macrophages, Peritoneal; Male; Mice, Inbred C57BL; Mice, Knockout; Peritonitis; Protective Factors; Punctures; Risk Factors; Sepsis; Thrombin; Thrombomodulin; Time Factors

Sepsis is characterized by systemic activation of inflammation and coagulation in response to infection. In sepsis, activated neutrophils extrude neutrophil extracellular traps composed of cell-free DNA (CFDNA) that not only trap pathogens but also provide a stimulus for clot formation. Although the effect of CFDNA on coagulation has been extensively studied, much less is known about the impact of CFDNA on fibrinolysis. To address this, we (1) investigated the relationship between CFDNA levels and fibrinolytic activity in sepsis and (2) determined the mechanisms by which CFDNA modulates fibrinolysis.. Plasma was collected from healthy and septic individuals, and CFDNA was quantified. Clot lysis assays were performed in plasma and purified systems, and lysis times were determined by monitoring absorbance. Clot morphology was assessed using scanning electron microscopy. Clots formed in plasma from septic patients containing >5 µg/mL CFDNA were dense in structure and resistant to fibrinolysis, a phenomenon overcome by deoxyribonuclease addition. These effects were recapitulated in control plasma supplemented with CFDNA. In a purified system, CFDNA delayed fibrinolysis but did not alter tissue-type plasminogen activator-induced plasmin generation. Using surface plasmon resonance, CFDNA bound plasmin with a Kd value of 4.2±0.3 µmol/L, and increasing concentrations of CFDNA impaired plasmin-mediated degradation of fibrin clots via the formation of a nonproductive ternary complex between plasmin, CFDNA, and fibrin.. Our studies suggest that the increased levels of CFDNA in sepsis impair fibrinolysis by inhibiting plasmin-mediated fibrin degradation, thereby identifying CFDNA as a potential therapeutic target for sepsis treatment.

Topics: Adult; Aged; Aged, 80 and over; Blood Coagulation; Case-Control Studies; DNA; Extracellular Traps; Female; Fibrin; Fibrin Clot Lysis Time; Fibrinogen; Fibrinolysin; Fibrinolysis; Humans; Male; Microscopy, Electron, Scanning; Middle Aged; Plasminogen; Protein Binding; Sepsis; Surface Plasmon Resonance; Time Factors; Tissue Plasminogen Activator; Young Adult

Sepsis has a profound impact on the inflammatory and hemostatic systems. In addition to systemic inflammation, it can produce disseminated intravascular coagulation, microvascular thrombosis, consumptive coagulopathy, and multiple organ failure. We have shown that treatment with suberoylanilide hydroxamic acid (SAHA), a histone deacetylase inhibitor (HDACI), improves survival in a lethal model of cecal ligation and puncture (CLP) in mice, but its effect on coagulation remains unknown. The goal of this study was to quantify the impact of SAHA treatment on coagulopathy in sepsis.. C57BL/6J mice were subjected to CLP, and 1 hour later given intraperitoneally either SAHA dissolved in dimethyl sulfoxide (DMSO) or DMSO only. Sham-operated animals were handled in similar manner without CLP. Blood samples were collected by cardiac puncture and evaluated using the TEG 5000 Thrombelastograph Hemostasis Analyzer System.. Compared with the sham group, all animals in DMSO vehicle group died within 72 hours, and developed coagulopathy that manifested as prolonged initial fibrin formation and fibrin cross-linkage time, and decreased clot formation speed, platelet function, and clot rigidity. SAHA treatment significantly improved survival and was associated with improvement in fibrin cross-linkage and clot formation, as well as platelet function and clot rigidity, without a significant impact on the clot initiation parameters.. SAHA treatment enhances survival and attenuates sepsis-associated coagulopathy by improving fibrin cross-linkage, rate of clot formation, platelet function, and clot strength. HDACI may represent a novel therapeutic strategy for correcting sepsis-associated coagulopathy.

Topics: Animals; Blood Coagulation; Blood Coagulation Disorders; Blood Platelets; Disease Models, Animal; Disseminated Intravascular Coagulation; Fibrin; Histone Deacetylase Inhibitors; Hydroxamic Acids; Male; Mice; Mice, Inbred C57BL; Sepsis; Thrombelastography; Vorinostat

Sepsis is associated with systemic inflammatory responses and induction of intravascular fibrin formation. Our aim is to investigate whether three fibrin-related markers (FRM) reflect the extent of coagulation activation in vivo and evaluate their clinical usefulness in identifying as well as monitoring patients with sepsis. Fibrin-degradation products (FDP), D-dimer and soluble fibrin monomer assays were measured on plasma samples from patients in the ICU with sepsis (n = 37), systemic inflammatory response syndrome (SIRS) (n = 35) and healthy individuals (n = 15). The levels were correlated with each other and also with fibrinogen, prothrombin time, platelets and antithrombin III. Clinical correlation was also performed for the diagnosis of sepsis and longitudinal monitoring for survival or death.There was strong correlation between the three FRM (r = 0.38-0.93, P < 0.0001) with only fibrin monomer correlating significantly with prothrombin time, fibrinogen and platelet levels. Clinically, all three FRM could discriminate between patients with sepsis, SIRS and healthy individuals with FDP, and D-dimer showing statistical significance (P < 0.05). No FRM predicted outcome from a single measurement but FDP was significantly able to predict patient survival from serial samples [mean FDP (μg/ml) from 35.36 to 21.37 (first to third ICU-day), P < 0.05]. Fibrin monomer appears the most sensitive indicator of coagulation activation, whereas D-dimer and FDP levels can significantly differentiate ICU patients with sepsis from those without. In addition, FDP would be preferable for monitoring with its statistically significant time-dependent prediction of survival or death from sepsis.

Topics: Aged; Antithrombin III; Biomarkers; Blood Platelets; Case-Control Studies; Diagnosis, Differential; Female; Fibrin; Fibrin Fibrinogen Degradation Products; Humans; Male; Middle Aged; Prognosis; Prothrombin Time; Sepsis; Survival Analysis; Systemic Inflammatory Response Syndrome

We prospectively studied (1) the relationships between angiogenic factors, their soluble receptors and organ dysfunction and (2) the effects of disseminated intravascular coagulation (DIC)-induced platelet consumption, thrombin generation, and tissue hypoxia on the expression of the factors and receptors. Fifty patients with sepsis were classified into two subgroups: 37 patients with DIC and 13 patients without DIC. DIC patients showed higher Sequential Organ Failure Assessment (SOFA) scores, the prevalence of multiple organ dysfunction syndrome (MODS) and more increased soluble fibrin and lactate levels. We observed lower levels of vascular endothelial growth factor (VEGF), soluble VEGF receptor 2 (sVEGFR2), angiopoietin 1 (Ang1) and Ang1/Ang2, and higher sVEGFR1 and Ang2 levels in DIC patients, but not significant differences in soluble Tie2 expression during the study period. The levels of VEGF, sVEGFR1, and Ang2 in DIC patients correlated with the SOFA scores. Clear differences were observed in the levels of Ang2 in the DIC patients between survivors and nonsurvivors and between those with and without MODS. The area under receiver operating characteristic curves for predicting death and MODS by Ang2 were 0.710 and 0.784, respectively. The VEGF levels showed a marked correlation with the platelet counts. Soluble fibrin and lactate levels independently predicted increases in the levels of VEGF, sVEGFR1, and Ang2 in DIC patients. In conclusion, VEGF, sVEGFR1, Ang2, and Ang1/Ang2, especially Ang2, may have roles in the development of MODS in sepsis associated with DIC, and VEGF, sVEGFR1, and Ang2 serum levels correlated with the extent of DIC-induced platelet consumption, thrombin generation, and blood lactate levels.

Topics: Angiogenesis Inducing Agents; Angiopoietin-1; Angiopoietin-2; Blood Platelets; Cell Hypoxia; Disseminated Intravascular Coagulation; Female; Fibrin; Humans; Lactic Acid; Male; Middle Aged; Multiple Organ Failure; Neovascularization, Physiologic; Platelet Count; Prospective Studies; ROC Curve; Sepsis; Thrombin; Treatment Outcome; Vascular Endothelial Growth Factor Receptor-2; Vascular Endothelial Growth Factors

Inflammation in sepsis is associated with hypercoagulation that may lead to thrombosis and disseminated intravascular coagulation. Conventional diagnostic assays are poorly sensitive to procoagulant changes in sepsis. Objectives of the article is to study changes in hemostatic state of septic patients using spatial clot growth assay (currently being developed under the trademark of thrombodynamics) and to compare the sensitivity of this method with the sensitivity of conventional methods. Sixteen patients with hematological malignancies and sepsis were enrolled in the study. All patients had been surveyed for a month following the infection onset. Spatial clot growth assay monitors fibrin clot development in a nonstirred thin layer of platelet-free plasma activated by immobilized tissue factor. Clotting time tests, thromboelastography, D-dimer assays were also performed. Spatial clot growth revealed hypercoagulation in six patients. D-dimer levels increase (with vein thrombosis in one case) was subsequently observed in five of them. D-dimer levels did not increase when spatial clot growth was normal. At the next time point, after spatial clot growth assay showed hypercoagulation, the mean D-dimer concentration was significantly higher than after a normal analysis (457 versus 234 μg/l; P < 0.05); there was no such correlation for other assays. The remaining 10 patients had elevated D-dimer levels on the first day; this either decreased gradually or remained elevated. Spatial clot growth showed normalization in survivors and growing hypocoagulation in nonsurvivors. Measuring spatial clot growth dynamics has potential diagnostic utility for the evaluation of thrombotic risk.

Topics: Adult; Blood Coagulation Tests; Female; Fibrin; Fibrin Fibrinogen Degradation Products; Hematologic Neoplasms; Humans; Male; Middle Aged; Predictive Value of Tests; Sepsis; Survival Analysis; Thrombosis

Improper compartmentalization of the inflammatory response leads to systemic inflammation in sepsis. Hemoadsorption (HA) is an emerging approach to modulate sepsis-induced inflammation. We sought to define the effects of HA on inflammatory compartmentalization in Escherichia coli-induced fibrin peritonitis in rats.. HA both reprograms and recompartmentalizes inflammation in sepsis. Sprague Dawley male rats were subjected to E. coli peritonitis and, after 24 h, were randomized to HA or sham treatment (sepsis alone). Venous blood samples collected at 0, 1, 3 and 6 h (that is, 24-30 h of total experimental sepsis), and peritoneal samples collected at 0 and 6 h, were assayed for 14 cytokines along with NO(2)(-/)NO(3)(-). Bacterial counts were assessed in the peritoneal fluid at 0 and 6 h. Plasma tumor necrosis factor (TNF)-α, interleukin (IL)-6, CXCL-1, and CCL2 were significantly reduced in HA versus sham. Principal component analysis (PCA) suggested that inflammation in sham was driven by IL-6 and TNF-α, whereas HA-associated inflammation was driven primarily by TNF-α, CXCL-1, IL-10 and CCL2. Whereas -peritoneal bacterial counts, plasma aspartate transaminase levels and peritoneal IL-5, IL-6, IL-18, interferon (IFN)-γ and NO(2)(-)/NO(3)(-) were significantly lower, both CXCL-1 and CCL2 as well as the peritoneal-to-plasma ratios of TNF-α, CXCL-1 and CCL2 were significantly higher in HA versus sham, suggesting that HA-induced inflammatory recompartmentalization leads to the different inflammatory drivers discerned in part by PCA. In conclusion, this study demonstrates the utility of combined in vivo/in silico methods and suggests that HA exerts differential effects on mediator gradients between local and systemic compartments that ultimately benefit the host.

Topics: Adsorption; Animals; Biomarkers; Colony Count, Microbial; Computational Biology; Escherichia coli; Fibrin; Hemofiltration; Inflammation; Inflammation Mediators; Liver; Male; Peritoneum; Peritonitis; Principal Component Analysis; Rats; Rats, Sprague-Dawley; Sepsis

Gram-negative sepsis is accompanied by a disproportionate innate immune response and excessive coagulation mainly induced by endotoxins released from bacteria. Due to rising antibiotic resistance and current lack of other effective treatments there is an urgent need for new therapies. We here present a new treatment concept for sepsis and endotoxin-mediated shock, based on host defense peptides from the C-terminal part of human thrombin, found to have a broad and inhibitory effect on multiple sepsis pathologies. Thus, the peptides abrogate pro-inflammatory cytokine responses to endotoxin in vitro and in vivo. Furthermore, they interfere with coagulation by modulating contact activation and tissue factor-mediated clotting in vitro, leading to normalization of coagulation responses in vivo, a previously unknown function of host defense peptides. In a mouse model of Pseudomonas aeruginosa sepsis, the peptide GKY25, while mediating a modest antimicrobial effect, significantly inhibited the pro-inflammatory response, decreased fibrin deposition and leakage in the lungs, as well as reduced mortality. Taken together, the capacity of such thrombin-derived peptides to simultaneously modulate bacterial levels, pro-inflammatory responses, and coagulation, renders them attractive therapeutic candidates for the treatment of invasive infections and sepsis.

Topics: Animals; Blood Coagulation; Cytokines; Disease Models, Animal; Endotoxins; Escherichia coli; Fibrin; Flow Cytometry; Humans; Inflammation; Lipopolysaccharides; Male; Mice; Mice, Inbred C57BL; Microscopy, Electron, Scanning; Peptides; Pseudomonas aeruginosa; Sepsis; Shock, Septic; Thrombin

An alternative pathway for fibrinolysis that comprises leukocyte elastase and its interaction with the plasminogen activator-plasmin system has been suggested. Plasma levels of cross-linked fibrin degradation product by leukocyte elastase (e-XDP) were significantly increased in patients with sepsis induced disseminated intravascular coagulation (DIC) compared with healthy subjects (18.6±19.9 vs 0.58±0.47U/mL, p<0.001). Twenty seven unique spots were identified from e-XDP dominant patients by immune-purification and two-dimensional difference gel electrophoresis, and they contained fibrinogen Bβ-chain derived fragments Bβ Asp-164, Ser-200, Gln-301, Ala-354, Ile-484 and γ-chain derivatives γ Val-274 at their amino-termini by acquired and processed tandem mass spectrometer. The Sequential Organ Failure Assessment Scores in patients with e-XDPs levels 3-10U/mL were significantly lower than those with e-XDPs levels -3U/mL, 10-30U/mL, and 30- U/mL. The adjusted odds for 28-day mortality rate in patients with e-XDP levels less than 3U/mL (hazard ratio, 4.432; 95% CI, 1.557-12.615 [p=0.005]) were significantly higher than those in patients with e-XDP levels of 3-10U/mL. These data suggest that leukocyte elastase might contribute to the degradation of cross-linked fibrin in sepsis-induced DIC.

Topics: Aged; Disseminated Intravascular Coagulation; Female; Fibrin; Fibrin Fibrinogen Degradation Products; Fibrinolysin; Fibrinolysis; Humans; Leukocyte Elastase; Male; Middle Aged; Prognosis; Sepsis

Septic infections dysregulate hemostatic pathways, prompting coagulopathy. Nevertheless, anticoagulant therapies typically fail to protect humans from septic pathology. The data reported in this work may help to explain this discrepancy by demonstrating critical protective roles for coagulation leading to fibrin deposition during host defense against the Gram-negative bacterium Yersinia enterocolitica. After i.p. inoculation with Y. enterocolitica, fibrinogen-deficient mice display impaired cytokine and chemokine production in the peritoneal cavity and suppressed neutrophil recruitment. Moreover, both gene-targeted fibrinogen-deficient mice and wild-type mice treated with the anticoagulant coumadin display increased hepatic bacterial burden and mortality following either i.p. or i.v. inoculation with Y. enterocolitica. Mice with low tissue factor activity succumb to yersiniosis with a phenotype similar to fibrin(ogen)-deficient mice, whereas factor XI-deficient mice show wild-type levels of resistance. Mice deficient in plasminogen activator inhibitor-1 or thrombin-activatable fibrinolysis inhibitor display modest phenotypes, but mice deficient in both plasminogen activator inhibitor-1 and thrombin-activatable fibrinolysis inhibitor succumb to yersiniosis with a phenotype resembling fibrin(ogen)-deficient mice. These findings demonstrate critical protective roles for the tissue factor-dependent extrinsic coagulation pathway during host defense against bacteria and caution that therapeutics targeting major thrombin-generating or antifibrinolytic pathways may disrupt fibrin-mediated host defense during Gram-negative sepsis.

Topics: Animals; Carboxypeptidase B2; Factor XI; Fibrin; Humans; Liver; Mice; Mice, Knockout; Sepsis; Serpin E2; Thromboplastin; Yersinia enterocolitica; Yersinia Infections

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Antithrombins; Disseminated Intravascular Coagulation; Female; Fibrin; Humans; Male; Middle Aged; Recombinant Proteins; Sepsis; Thrombomodulin

ExoU, a Pseudomonas aeruginosa cytotoxin with phospholipase A2 activity, was shown to induce vascular hyperpermeability and thrombus formation in a murine model of pneumosepsis. In this study, we investigated the toxin ability to induce alterations in pulmonary fibrinolysis and the contribution of the platelet activating factor (PAF) in the ExoU-induced overexpression of plasminogen activator inhibitor-1 (PAI-1).. Mice were intratracheally instilled with the ExoU producing PA103 P. aeruginosa or its mutant with deletion of the exoU gene. After 24 h, animal bronchoalveolar lavage fluids (BALF) were analyzed and lung sections were submitted to fibrin and PAI-1 immunohistochemical localization. Supernatants from A549 airway epithelial cells and THP-1 macrophage cultures infected with both bacterial strains were also analyzed at 24 h post-infection.. In PA103-infected mice, but not in control animals or in mice infected with the bacterial mutant, extensive fibrin deposition was detected in lung parenchyma and microvasculature whereas mice BALF exhibited elevated tissue factor-dependent procoagulant activity and PAI-1 concentration. ExoU-triggered PAI-1 overexpression was confirmed by immunohistochemistry. In in vitro assays, PA103-infected A549 cells exhibited overexpression of PAI-1 mRNA. Increased concentration of PAI-1 protein was detected in both A549 and THP-1 culture supernatants. Mice treatment with a PAF antagonist prior to PA103 infection reduced significantly PAI-1 concentrations in mice BALF. Similarly, A549 cell treatment with an antibody against PAF receptor significantly reduced PAI-1 mRNA expression and PAI-1 concentrations in cell supernatants, respectively.. ExoU was shown to induce disturbed fibrin turnover, secondary to enhanced procoagulant and antifibrinolytic activity during P. aeruginosa pneumosepsis, by a PAF-dependent mechanism. Besides its possible pathophysiological relevance, in vitro detection of exoU gene in bacterial clinical isolates warrants investigation as a predictor of outcome of patients with P. aeruginosa pneumonia/sepsis and as a marker to guide treatment strategies.

Topics: Animals; Bacterial Proteins; Blood Coagulation; Bronchoalveolar Lavage Fluid; Cell Line, Tumor; Disease Models, Animal; Epithelial Cells; Female; Fibrin; Humans; Immunohistochemistry; Macrophages; Mice; Mutation; Plasminogen Activator Inhibitor 1; Platelet Activating Factor; Pneumonia, Bacterial; Pseudomonas aeruginosa; Pseudomonas Infections; Pulmonary Alveoli; Respiratory Mucosa; RNA, Messenger; Sepsis; Time Factors; Up-Regulation

Severe sepsis remains a leading cause of death and disability because of less effective therapy available for this disease. A complex interplay between the inflammatory factors and the coagulation pathways seems to be the fundamental mechanisms for the pathogenesis of sepsis. Here we report that recombinant fibrinogenase II (rF II) from Agkistrodon acutus plasmin-independently degraded the thrombi, and inhibited inflammatory responses by direct and specific degradation of tumor necrosis factor alpha (TNF-alpha) induced by lipopolysaccharide (LPS) without showing proteolytic activities on interleukin-1 (IL-1), cluster of differentiation 68 (CD68) and some other serum proteins. We also report that rF II effectively protected against LPS induced sepsis in a rabbit model. Administration of rF II reduced hepatic and renal damage, decreased the levels of alanine aminotransferase (ALT) and blood urea nitrogen (BUN), and increased survival rate in LPS-induced sepsis rabbits. We further confirmed the rescue effect of rF II on severe sepsis in rat caecal ligation and puncture (CLP) model. Our findings suggest that rF II could effectively protect against sepsis via direct degradation of microthrombi and inflammatory factor TNF-alpha as well as provide a novel strategy to develop a single proteinase molecule for targeting the main pathological processes of this disease.

Topics: Agkistrodon; Animals; Base Sequence; Crotalid Venoms; DNA Primers; Fibrin; Hydrolysis; Microscopy, Fluorescence; Molecular Sequence Data; Rabbits; Rats; Recombinant Proteins; Reverse Transcriptase Polymerase Chain Reaction; Sepsis; Serine Endopeptidases; Tumor Necrosis Factor-alpha

Severe pneumonia is associated with a local inhibition of fibrinolysis in the lung as reflected by strongly reduced pulmonary plasminogen activator activity.. To study the effect of elevation of local plasminogen activator activity during pneumonia caused by the common respiratory pathogen Klebsiella pneumoniae.. Female C57Bl/6 mice were inoculated intranasally with a replication-defective adenoviral vector expressing human tissue-type plasminogen activator or a control vector 24 h before intranasal infection with K. pneumoniae.. Mice infected with Klebsiella via the airways developed overt pneumonia, which was accompanied by a downregulation of pulmonary tissue-type plasminogen activator levels at protein and mRNA levels. Pulmonary overexpression of human tissue-type plasminogen activator resulted in increased fibrinolytic activity in the lungs during pneumonia, as indicated by higher D-dimer levels and reduced fibrin deposition. Interestingly, overexpression of tissue-type plasminogen activator markedly improved host defense against pneumonia: mice treated with the tissue-type plasminogen activator vector displayed less bacterial growth and dissemination, attenuated distant organ injury and a reduced mortality.. These data demonstrate that local elevation of plasminogen activator activity in the lungs improves host defense against severe gram-negative pneumonia and sepsis.

Topics: Adenoviridae; Administration, Intranasal; Animals; Female; Fibrin; Fibrin Fibrinogen Degradation Products; Fibrinolysis; Genetic Vectors; Humans; Immunity, Innate; Klebsiella Infections; Klebsiella pneumoniae; Lung; Mice; Mice, Inbred C57BL; Pneumonia, Bacterial; Recombinant Fusion Proteins; RNA, Messenger; Sepsis; Tissue Plasminogen Activator; Transgenes

To track the natural history of tunneled hemodialysis catheters requiring removal or exchange at a single institution.. Over a 2-year period, tunneled hemodialysis catheters that presented to interventional radiology for removal or exchange were entered into this retrospective study. Patient demographics, catheter location, dwell time, and indication for removal were recorded. Pull-back contrast venography was performed with imaging over the chest. Catheters were then removed or exchanged.. Three hundred thirty-four tunneled dialysis catheters were removed or exchanged in 207 patients; 108 male, median age 53 years. Dwell time, available from 296 catheters, ranged from 1 to 114 days (median, 66 days) for a total of 32,847 catheter days. One hundred three catheters were removed for infection, yielding a rate of infection requiring catheter removal of 3.0 per 1,000 catheter days. One hundred catheters were removed for other working access, and 96 catheters were exchanged for poor function. Two hundred sixty-five were removed or exchanged from the internal jugular vein, 22 from the subclavian vein, and 24 from the femoral vein. One hundred seventy-two (76%) of the 226 catheters studied with contrast had fibrin sheaths; of which 42 had thrombus identified along the catheter tract. One hundred ninety-three catheters were removed, and 141 catheters were exchanged for new catheters with 82 catheters receiving balloon disruption of the fibrin sheath.. Approximately one third of tunneled dialysis catheters are removed for infection, one third for other working access, and one third for poor function. Catheters usually remain in the patient for a median of 2 months. Fibrin sheaths associated with hemodialysis catheters are very common. Thrombus formation around the sheath is frequent.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Catheterization, Central Venous; Catheters, Indwelling; Child; Child, Preschool; Device Removal; Equipment Failure; Female; Fibrin; Fluoroscopy; Humans; Male; Middle Aged; Radiography, Interventional; Renal Dialysis; Retrospective Studies; Sepsis; Thrombosis

Coagulopathy and thrombocytopenia often occur in critically ill patients, and disseminated intravascular coagulation (DIC) can lead to multiple organ dysfunction and a poor outcome. However, the relation between coagulopathy and systemic inflammatory response has not been thoroughly clarified. Thus, we evaluated coagulative activity, organ dysfunction, and systemic inflammatory response syndrome (SIRS) in critically ill patients with thrombocytopenia and examined the balance between coagulopathy and systemic inflammation.. Two hundred seventy-three patients, who were admitted to 13 critical care centers in Japan and fulfilled the criteria of platelet count of less than 150*10(9)/L, were included. Coagulative variables (platelet count, fibrin/fibrinogen degradation products, and DIC scores), organ dysfunction index (Sequential Organ Failure Assessment [SOFA] score), and SIRS score in each patient were evaluated for 4 consecutive days after fulfilling the above entry criteria. The effect of SIRS on coagulopathy and organ dysfunction was evaluated in these patients.. Both the maximum SIRS score and entry SIRS score had significant relation to the maximum SOFA score during the observation period. Coagulation disorders indicated by the minimum platelet count, maximum DIC scores, and positivity for DIC worsened gradually with increases in SIRS scores. Both the minimum platelet count and maximum DIC scores were significantly correlated with the maximum SOFA score, indicating that a relation exists between coagulopathy and organ dysfunction.. In critically ill patients with thrombocytopenia, coagulopathy and organ dysfunction progress with significant mutual correlation, depending on the increase in SIRS scores. The SIRS-associated coagulopathy may play a critical role in inducing organ dysfunction after severe insult.

Topics: Adult; Aged; Analysis of Variance; Blood Coagulation Disorders; Critical Illness; Disseminated Intravascular Coagulation; Female; Fibrin; Fibrin Fibrinogen Degradation Products; Humans; Male; Middle Aged; Multiple Organ Failure; Platelet Count; Sepsis; Systemic Inflammatory Response Syndrome; Thrombocytopenia

To unravel the strategy by which Brucella abortus establishes chronic infections, we explored its early interaction with innate immunity.. Brucella did not induce proinflammatory responses as demonstrated by the absence of leukocyte recruitment, humoral or cellular blood changes in mice. Brucella hampered neutrophil (PMN) function and PMN depletion did not influence the course of infection. Brucella barely induced proinflammatory cytokines and consumed complement, and was strongly resistant to bactericidal peptides, PMN extracts and serum. Brucella LPS (BrLPS), NH-polysaccharides, cyclic glucans, outer membrane fragments or disrupted bacterial cells displayed low biological activity in mice and cells. The lack of proinflammatory responses was not due to conspicuous inhibitory mechanisms mediated by the invading Brucella or its products. When activated 24 h post-infection macrophages did not kill Brucella, indicating that the replication niche was not fusiogenic with lysosomes. Brucella intracellular replication did not interrupt the cell cycle or caused cytotoxicity in WT, TLR4 and TLR2 knockout cells. TNF-alpha-induction was TLR4- and TLR2-dependent for live but not for killed B. abortus. However, intracellular replication in TLR4, TLR2 and TLR4/2 knockout cells was not altered and the infection course and anti-Brucella immunity development upon BrLPS injection was unaffected in TLR4 mutant mice.. We propose that Brucella has developed a stealth strategy through PAMPs reduction, modification and hiding, ensuring by this manner low stimulatory activity and toxicity for cells. This strategy allows Brucella to reach its replication niche before activation of antimicrobial mechanisms by adaptive immunity. This model is consistent with clinical profiles observed in humans and natural hosts at the onset of infection and could be valid for those intracellular pathogens phylogenetically related to Brucella that also cause long lasting infections.

Topics: Animals; Bacteremia; Blood Coagulation; Brucella abortus; Brucellosis; Fibrin; Fibrinogen; Immunity, Innate; Leukocytes; Mice; Neutrophils; Platelet Aggregation; Sepsis; Shock, Septic

Tissue factor (TF) is a transmembrane protein, which is essential for initiation of the coagulation cascade. TF has been reported to play an important role in the progression of endotoxin (lipopolysaccharide, LPS)-mediated endotoxemia, being induced in numerous tissues, such as kidney, spleen and lung. We developed and validated a rabbit anti-murine TF peptide antiserum to localize TF protein in a murine sepsis model. TF protein distribution was compared to localization of TF mRNA and fibrin deposits, the ultimate resultant of procoagulant TF activity. Evident LPS mediated TF mRNA induction was observed in the tubular area at the cortico-medullar junction in the kidney, and TF activity was increased after 6 hours of endotoxemia. In the spleen, however, TF mRNA was induced in the interfollicular region upon LPS injection, corresponding to increased TF protein in the same area. The clusters of TF-protein positive cells in the spleen are predominantly granulocytes, but no TF mRNA expression was observed within these cells. Based on these observations and the presence of TF-protein positive granulocytes after splenectomy, we hypothesize that granulocytes take-up TF for transport to other locations in order to initiate fibrin formation or to induce pro-inflammatory gene expression upon interaction with factor VIIa.

Topics: Animals; Endotoxemia; Female; Fibrin; Gene Expression Regulation; Granulocytes; Immune Sera; Inflammation; Kidney; Lipopolysaccharides; Mice; Protein Transport; Rabbits; RNA, Messenger; Sepsis; Spleen; Thromboplastin; Tissue Distribution

The factor V Leiden (FVL) mutation (Arg506Glu) results in the production of an FV protein that when activated is relatively resistant to inactivation by activated protein C and thereby leads to predisposition to thrombosis. The rather high prevalence of the FVL mutation in the general population prompted speculation about a potential survival benefit for individuals carrying the FVL allele. Indeed, both clinical and experimental animal data suggest that a heterozygous FVL genotype might protect against the lethal consequences of sepsis. We sought to confirm the survival advantage of heterozygous FVL mice in septic disease.. Controlled animal experiment.. Academic research laboratory.. Wild-type, heterozygous, and homozygous FVL mice subjected to 1 x 10 live bacteria as model for septic peritonitis.. None.. The intraperitoneal injection of E. coli led to growth and dissemination of bacteria and provoked an inflammatory response as evident from elevated cytokine levels (interleukin-6, interleukin-10, and tumor necrosis factor-alpha), induced thrombin-antithrombin complex levels, increased granulocyte influx into the peritoneal cavity, liver necrosis, and adhesion of leukocytes to the vessel wall, resulting in approximately 50% mortality after 72 hrs. The FVL genotype had no significant effect on bacterial outgrowth, markers of inflammation (i.e., tumor necrosis factor-alpha levels of 152 [96.2-200], 152 [99.7-1745], and 110 [99.7-177] pg/mL in peritoneal lavage fluid at t = 20 hrs for wild-type, heterozygous, and homozygous FVL mice, respectively), thrombin generation (i.e., thrombin-antithrombin complex levels of 19.9 [9.31-37.4], 10.4 [6.55-15.8], and 12.6 [8.24-29.0] ng/mL in peritoneal lavage fluid at t = 6 hrs for wild-type, heterozygous, and homozygous FVL mice, respectively), and/or survival (50%, 36%, and 50% for wild-type, heterozygous, and homozygous FVL mice, respectively).. The FVL allele has no beneficial effect in mouse septic peritonitis, and the general protective effect of FVL in sepsis needs further investigation.

Topics: Animals; Antithrombin III; Ascitic Fluid; Cell Adhesion; Cytokines; Disease Models, Animal; Escherichia coli; Factor V; Fibrin; Genotype; Granulocytes; Heterozygote; Homozygote; Kidney; Leukocytes; Liver; Lung; Mice; Mice, Transgenic; Necrosis; Peptide Hydrolases; Peritoneal Lavage; Peritonitis; Point Mutation; Sepsis; Thrombosis

Topics: Animals; Disseminated Intravascular Coagulation; Fibrin; Immunoglobulins, Intravenous; Immunologic Factors; Interleukin-6; Kidney Glomerulus; Sepsis; Tumor Necrosis Factors

The liver can be injured and its functions altered by activation of the coagulation and inflammatory processes in sepsis. The objective of the present study was to investigate the pattern of protease- activated receptors (PARs) over time in a model of acute liver injury induced by lipopolysaccharide (LPS); and whether PARs play a role in this process and exert their effects through inflammation and coagulation. Levels of tumor necrosis factor-a (TNF-a) were significantly expressed 1 h after LPS administration followed by: i) an increase in levels of tissue factor, factor VIIa, thrombin and plasminogen activator inhibitor-1; ii) unchanged or steady levels of tissue factor pathway inhibitor; and iii) subsequent deposition of fibrin in the liver tissue, that led to the elevation of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), which are associated with liver injury. The expression of all PAR isoforms (1-4) was elevated, and each isoform had a distinct cellular localization (hepatocytes, Kupffer cells, the portal triad area, and central veins) and a time-dependent pattern of expression. The immuno-reactivity of PAR2 and 4 in Kupffer cells was intense. Interestingly, PAR2 blocking peptide improved the healing of liver injuries, an effect that was associated with suppression of TNF-a elevation, and normalization of coagulation and fibrinolysis. This ultimately led to decreased fibrin formation in the injured liver. The present study reveals a distinct chronological expression and cellular localization of PARs in LPS-mediated liver injury and shows that blockade of PAR2 may play a crucial role in treating liver injury, via normalization of inflammation, coagulation and fibrinolytic pathways.

Topics: Acute Disease; Animals; Blood Coagulation; Blood Coagulation Factors; Chemical and Drug Induced Liver Injury; Disease Models, Animal; Fibrin; Fibrinolysis; Humans; Lipopolysaccharides; Liver; Liver Diseases; Peptides; Protein Isoforms; Rats; Rats, Wistar; Receptor, PAR-1; Receptor, PAR-2; Receptors, Proteinase-Activated; Receptors, Thrombin; RNA, Messenger; Sepsis; Time Factors; Tumor Necrosis Factor-alpha

It is well known that disorders of coagulation and fibrinolysis play a major role in the development of organ dysfunction during sepsis. Furthermore, the importance of the early initiation of anticoagulation therapy for severe cases has been emphasized based on the success of recent clinical trials. The purpose of this study is to search for useful markers for predicting organ dysfunction. Plasma samples were prospectively collected from 78 patients within 48 h after the onset of sepsis. Hemostatic markers and endothelial damage markers were compared between the patients with and without organ dysfunction. The WBC and platelet counts were not different between the groups. In contrast, fibrin/fibrinogen degradation products, D-dimer, thrombin-antithrombin complex, plasmin alpha2-antiplasmin complex, soluble fibrin, and total plasminogen activator inhibitor-1 were significantly higher, and the antithrombin activity and protein C levels were lower in the patients with organ dysfunction. Thus, the changes in the hemostatic molecular markers were associated with organ dysfunction from an early stage of sepsis, and antithrombin and protein C activities were found to be the most reliable markers.

Topics: Adult; Aged; alpha-2-Antiplasmin; Antithrombin III; Antithrombins; Area Under Curve; Biomarkers; Blood Cell Count; Blood Coagulation Tests; Endothelium, Vascular; Female; Fibrin; Fibrin Fibrinogen Degradation Products; Hemostasis; Humans; Male; Middle Aged; Peptide Hydrolases; Plasminogen Activator Inhibitor 1; ROC Curve; Sepsis; Time Factors

Disseminated intravascular coagulation (DIC) is a major factor influencing mortality in neonatal sepsis.(1) Clinical trials have supported the use of antithrombin and activated protein C supplementation in DIC associated with sepsis.

Topics: Case-Control Studies; Disseminated Intravascular Coagulation; Fibrin; Humans; Infant, Newborn; Predictive Value of Tests; Sensitivity and Specificity; Sepsis; Solubility

To evaluate the significance of the changes in plasma thrombus precursor protein (TPP) in severe sepsis.. Enzyme linked immunoadsorbent assay (ELISA) was used in the determination of plasma TPP in 22 patients with severe sepsis group. Prothrombin time (PT), activated partial thromboplastin time(APTT), fibrin(Fib), D-Dimer were also determined and the values were compared with those obtained from 10 patients with infection and 8 healthy normal controls. At the same time, scores of sepsis related organ failure assessment(SOFA), simplified acute physiology score (SAPSII), Marshall criteria were made respectively in patients with severe sepsis on 1,3,5 days after admission to the ICU. Analysis of correlation between TPP and scores was done.. (1)The concentration of TPP and positive rate of D-Dimer in severe sepsis were obviously higher than that in the ordinary infection group and normal control group (all P<0.05). But there were no differences in levels of PT, APTT, and Fib among three groups. (2)The concentration of TPP rose continuously in nonsurvivors due to severe sepsis, and it was positively correlated with scores of SOFA, SAPSII, Marshall criteria.. TPP levels showed a higher specificity and sensitivity in detecting hypercoagulability state in severe than D-Dimer, PT, APTT, Fib assay. It can be used as a diagnostic and prognostic parameter for early hypercoagulability states and outcome of severe sepsis.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Blood Coagulation; Female; Fibrin; Humans; Male; Middle Aged; Prognosis; Sensitivity and Specificity; Sepsis; Young Adult

Previous studies have shown that blocking endothelial protein C receptor (EPCR)-protein C interaction results in about an 88% decrease in circulating activated protein C (APC) levels generated in response to thrombin infusion and exacerbates the response to Escherichia coli. To determine whether higher levels of EPCR expression on endothelial cells might further enhance the activation of protein C and protect the host during septicemia, we generated a transgenic mouse (Tie2-EPCR) line which placed the expression of EPCR under the control of the Tie2 promoter. The mice express abundant EPCR on endothelial cells not only on large vessels, but also on capillaries where EPCR is generally low. Tie2-EPCR mice show higher levels of circulating APC after thrombin infusion. Upon infusion with factor Xa and phospholipids, Tie2-EPCR mice generate more APC, less thrombin and are protected from fibrin/ogen deposition compared with wild type controls. The Tie2-EPCR animals also generate more APC upon lipopolysaccharide (LPS) challenge and have a survival advantage. These results reveal that overexpression of EPCR can protect animals against thrombotic or septic challenge.

Topics: Animals; Antibodies, Monoclonal; Blood Coagulation Factors; Cell Separation; Disease Progression; Endothelium, Vascular; Endotoxins; Escherichia coli; Fibrin; Fibrinogen; Flow Cytometry; Hemostasis; Hemostatics; Lipopolysaccharides; Mice; Mice, Transgenic; Promoter Regions, Genetic; Protein C; Receptor, TIE-2; Receptors, Cell Surface; Reverse Transcriptase Polymerase Chain Reaction; Sepsis; Thrombin; Thrombosis; Time Factors; Transgenes

Topics: Biomarkers; Disseminated Intravascular Coagulation; Fibrin; Fibrinogen; Humans; Intensive Care Units; Multiple Organ Failure; Platelet Count; Prothrombin Time; Sepsis; Severity of Illness Index

Plasma levels of granulocyte-derived elastase (GE-XDP), D-dimer, and soluble fibrin (SF) were examined in 177 patients with disseminated intravascular coagulation (DIC) of various etiologies. Plasma levels of GE-XDP and D-dimer, but not SF, were significantly high in patients with sepsis and solid cancer. The ratio of GE-XDP/ D-dimer was significantly high in patients with trauma, burn, and sepsis, suggesting that fibrinolysis due to GE-XDP may be dominant in DIC. Plasma levels of GE-XDP and D-dimer, but not SF, were significantly high in patients with overt DIC and correlated with DIC score. Plasma levels of GE-XDP, but not SF, correlated significantly with D-dimer. Plasma levels of D-dimer, but not SF, correlated significantly with plasmin plasmin inhibitor complex (PPIC). Plasma levels of GE-XDP and D-dimer, but not SF, were significantly high in nonsurvivors. Plasma levels of GE-XDP, but not SF, correlated significantly with sepsis-related organ failure assessment (SOFA) score. These results suggest that GE-XDP is a potentially useful marker for the diagnosis of overt-DIC and as a predictor of organ failure-related outcome.

Topics: Biomarkers; Disseminated Intravascular Coagulation; Female; Fibrin; Fibrin Fibrinogen Degradation Products; Fibrinolysin; Humans; Leukocyte Elastase; Male; Plasma; Protein Binding; Sepsis; Solubility

Although sepsis-induced release of nitric oxide (NO) is known to have an antithrombotic effect, it is unknown if NO exerts this same effect under physiological conditions. We have there-fore attempted to determine whether or not NO protects against thrombus formation in normal Wistar rats injected with various amounts (0.8, 4.0, 20.0 and 100 mg/kg/4 hr) of L-NAME (N (omega)-nitro-l-arginine methyl ester), an NO synthase inhibitor, via the tail vein. Plasma levels of D-dimer fragments of fibrin were significantly increased in rats receiving L-NAME (0.21+/-0.04, 0.22+/-0.05, 0.26+/-0.07, 0.59+/-0.17 micro g/mL, means+/-SE; p<0.05, 0.05, 0.05, 0.01: L-NAME 0.8, 4, 20, 100, respectively, compared with control levels: <0.06 micro g/mL), and thrombin-anti-thrombin complex (TAT) levels were significantly increased in rats receiving 20mg/kg/4 hr or greater doses of L-NAME (4.5+/-1.1, 4.7+/-1.4, 18.7+/-4.9, 42.5+/-4.0 ng/mL, NS, NS, p<0.05, 0.01, respectively, compared with control levels: 3.8+/-1.2 ng/mL). Glomerular fibrin deposition was increased in a dose-dependent manner in rats receiving L-NAME (6.8+/-1.5, 13.9+/-1.6, 32.4+/-2.6, 49.2+/-5.2%, p<0.05, 0.05, 0.01, 0.01, respectively, com-pared with control levels: 0.0+/-0.0%). Renal dysfunction and hepatic dysfunction were observed in rats receiving 20mg/kg/4 hr or greater, or 100mg/kg/4 hr, doses of L-NAME, respectively. Mean blood pressure was also elevated in rats receiving L-NAME in a dose-dependent manner. These findings suggest that NO, in addition to regulating blood pressure, is involved in prevention of thrombus formation under physiological circumstances.

Topics: Animals; Antithrombins; Arteries; Blood Pressure; Dimerization; Dose-Response Relationship, Drug; Endothelium; Fibrin; Fibrinolytic Agents; Male; NG-Nitroarginine Methyl Ester; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Nitric Oxide Synthase Type III; Rats; Rats, Wistar; Sepsis

A 31-year-old man who underwent chemotherapy and bone marrow transplantation to treat acute myeloblastic leukemia was admitted to our department complaining of high fever and hypotension. His physical examination revealed warm shock state, eruptions resembling that seen in systemic lupus erythematosus on his face and cyanosis in his fingers. We diagnosed septic shock and idiopathic skin eruption on his face. Following treatment with blood transfusion, anticoagulant, antibiotics, respirator and continuous arteriovenous hemofiltration and dialysis, the patient's condition gradually improved. The eruptions on his face first observed at admission progressed with a worsening of his disseminated intravascular coagulation (DIC), and subsided with an improvement in his DIC. A biopsy of the eruption was taken and pathological findings of the eruption revealed multiple micro-fibrin depositions of the dermis. The skin necrosis in purpura fulminans often begins in the distal extremities. But our patient developed this uncommon skin eruption on his face. Patients with an idiopathic skin eruption resembling a butterfly rash in a septic patient should be considered to complicate DIC as in the present case.

Topics: Adult; Bone Marrow Transplantation; Disseminated Intravascular Coagulation; Exanthema; Face; Fibrin; Humans; IgA Vasculitis; Leukemia, Myeloid, Acute; Male; Necrosis; Sepsis

We investigated the correlation between disseminated intravascular coagulation (DIC) score and hemostatic parameters and sepsis-related organ failure assessment (SOFA) score with clinical outcome of patients with DIC in an intensive care unit (ICU). The SOFA score was markedly elevated in patients with DIC relative to patients without DIC and significantly higher in non-survivors than in survivors. Abnormalities in almost all hemostatic parameters were significant in patients with DIC, but there was no significant difference in almost all hemostatic parameters between survivors and non-survivors. However, plasma antithrombin (AT) levels were significantly lower in non-survivors than in survivors. Soluble fibrin (SF) and tissue type plasminogen activator (tPA)-plasminogen activator inhibitor-I (PAI-I) complex correlated significantly with the SOFA score, whereas AT levels correlated significantly and negatively with the SOFA score. We conclude that the SOFA score is useful for predicting outcome in DIC patients in the ICU, and that hemostatic parameters, especially plasma AT levels, are also useful markers for organ failure and clinical outcome.

Topics: Antithrombins; Biomarkers; Disseminated Intravascular Coagulation; Fibrin; Hemostasis; Humans; Intensive Care Units; Multiple Organ Failure; Plasminogen Activator Inhibitor 1; Sepsis; Severity of Illness Index; Tissue Plasminogen Activator

Fibrin persistence in the vasculature is an important complication of sepsis that can often lead to mortality. We have previously established that polymorphonuclear leukocytes (PMN) from healthy individuals have the capacity to degrade fibrin via urokinase-type plasminogen activator (u-PA). We have also demonstrated an increase in u-PA antigen in the plasma of patients suffering from septic shock. In this study, we investigate the hypothesis that PMN from patients with sepsis have lost their fibrinolytic ability and that this might contribute to the persistence of fibrin deposits. We show here that PMN from these patients do not express any u-PA activity, despite retaining some u-PA antigen. Additionally, thrombi prepared from the whole blood of the patients exhibit reduced endogenous lysis compared with those from healthy individuals. These data indicate that loss of fibrinolytic activity from PMN may be a contributing factor in fibrin persistence in the microvasculature in sepsis.

Topics: Antigens, Surface; Disseminated Intravascular Coagulation; Female; Fibrin; Fibrinolysis; Humans; Male; Neutrophils; Sepsis; Thrombosis; Urokinase-Type Plasminogen Activator

To monitor and better understand the immunoinflammatory sequelae in sepsis and septic shock, systemic and monocyte-related cytokine responses were evaluated in baboons with experimental peritonitis induced by an E. coli-laden fibrin clot. Despite similar bacterial inocula, considerable interindividual variability in clinical manifestation and outcome of infection was observed. Because monocytes and macrophages are a key component of innate immunity, we hypothesized that early polarization of distinct activation programs in circulating monocytes that culminates in the emergence of either classically (M1) or alternatively (M2) activated monocytes may underlie the observed susceptibility or resistance to infection. To test our hypothesis, we analyzed infection-induced expression of cytokine mRNAs in monocytes isolated from surviving and dead animals. Our data show that resistance to E. coli sepsis may well be associated with a mixed M1/M2 activation state of circulating monocytes, whereas M1 phenotype appeared to be prevailing in monocytes from animals that died. Together with data on systemic cytokine responses, the latter findings indicate that morbidity and mortality of animals with gram-negative sepsis may well result from an overwhelming proinflammatory response. Collectively, our data contribute to a better understanding of cytokine networking in the immunoinflammatory response to microbial infection and suggest M1/M2 immunophenotypic profiling of readily available circulatory monocytes for early prognosis of severe infections.

Topics: Animals; Cell Line; Cells, Cultured; Cytokines; DNA Primers; Endotoxins; Escherichia coli; Fibrin; Inflammation; Leukocytes, Mononuclear; Mice; Monocytes; Papio; Phenotype; Polymerase Chain Reaction; Prognosis; Reverse Transcriptase Polymerase Chain Reaction; RNA; RNA, Messenger; Sepsis; Time Factors

The alveolar fibrinolytic system is altered in acute lung injury (ALI). Levels of the fibrinolytic protease inhibitor, plasminogen activator inhibitor-1 (PAI-1), are too low in bronchoalveolar lavage to address its prognostic significance. This study was performed to assess whether PAI-1 antigen in undiluted pulmonary edema fluid levels can identify patients with ALI and predict their outcome. PAI-1 antigen levels in both plasma and edema fluid were higher in ALI compared with hydrostatic edema, and edema fluid PAI-1 values identified those with ALI with high sensitivity and specificity. Both the high plasma and edema fluid PAI-1 antigen values were associated with a higher mortality rate and fewer days of unassisted ventilation in patients with ALI. Differences in PAI-1 activity were concordant with levels of PAI-1 antigen. Although the fibrin-derived alveolar D-dimer levels were strikingly similar in both groups, ALI patients had a higher relative proportion of D-monomer. In conclusion, PAI-1 levels in edema fluid and plasma identify those with ALI that have a poor prognosis. The data indicate that fibrin turnover in early ALI is a consequence of a rapid fibrinogen influx and fractional fibrinolytic inhibition.

Topics: Acute Disease; Adult; Aged; Enzyme-Linked Immunosorbent Assay; Extravascular Lung Water; Female; Fibrin; Fibrin Fibrinogen Degradation Products; Fibrinogen; Fibrinolysis; Humans; Hydrostatic Pressure; Male; Middle Aged; Plasminogen Activator Inhibitor 1; Predictive Value of Tests; Prognosis; Pulmonary Edema; Sepsis

Successful establishment of sepsis by entrapping a dose of 150 colony forming units of Klebsiella pneumoniae in a fibrin clot following implantation into the peritoneal cavity of mice is reported. The dose in the fibrin clot gave 50% mortality in mice, spread over a period of one week. All the infected mice showed positive blood culture up to 6 d post-infection; histopathology revealed inflammatory changes in both liver and spleen. Introduction of K. pneumoniae into experimental mice without entrapment in fibrin clot caused no mortality and blood culture remained positive only up to 2 d; histopathology of liver and spleen throughout the period of study showed relatively mild inflammatory changes, which almost cleared during 14 d post-infection. The use of the fibrin-clot model may thus be considered to be useful in studying both the initial and the persisting stage of infection in the peritoneum, whence a slow release of bacteria into the blood takes place which finally leads to sepsis and septicemia.

Topics: Animals; Disease Models, Animal; Female; Fibrin; Klebsiella Infections; Klebsiella pneumoniae; Liver; Mice; Mice, Inbred Strains; Peritoneal Cavity; Sepsis; Spleen

Disseminated intravascular coagulation (DIC) is a syndrome characterized by systemic intravascular activation of coagulation leading to the widespread deposition of fibrin in the circulation. Therefore, the determination of soluble fibrin is crucial for the diagnosis of DIC. Thrombus precursor protein (TpP) levels can be determined as a measure of soluble polymers, which are the immediate precursors of insoluble fibrin. In this study, the potential diagnostic usefulness of this TpP test was investigated in septic patients with DIC and liver diseases.. TpP analysis was performed on 155 plasma samples from 95 septic patients, including 72 patients without liver disease and 23 patients with liver diseases, and on 42 plasma samples from normal healthy subjects. The study population was subdivided according to three phases of DIC described as compensated, decompensated and full-blown DIC. Plasma TpP level was determined using a new assay, the TpPTM (American Biogenetic Sciences, USA), which is based on an ELISA method.. Septic patients with decompensated (16.1 9.1 mg/mL) or full- blown (20.9 12.4 mg/mL) phases of DIC had significantly higher TpP levels than those with the compensated (5.6 6.2 mg/mL) phase of DIC or healthy controls (2.9 1.6 mg/mL). In septic patients with liver disease, a significant difference was found between the TpP levels of patients with full- blown DIC (21.6 10.6 mg/mL) and those of patients with the decompensated phase (13.4 6.5 mg/mL). Plasma TpP levels correlated significantly with other DIC parameters including platelet count, fibrinogen, antithrombin and TAT, and correlated weakly with D-dimer.. Our findings indicate that septic patients who developed decompensated or full-blown DIC or organ dysfunction have significantly higher plasma levels of TpP, and suggest the potential usefulness of the TpP assay as an aid to the diagnosis of DIC in cases of sepsis and liver disease complicated by sepsis.

Topics: Adult; Aged; Antithrombins; Female; Fibrin; Fibrinogen; Humans; Liver Diseases; Male; Middle Aged; Platelet Count; Sepsis

To determine whether fibrin-coated central venous catheters have a higher infection rate, and spawn more septic emboli, than uncoated catheters after exposure to bacteremia.. Animal study comparing catheter infection and blood cultures of fibrin-coated and uncoated catheters exposed to bacteremia.. Animal laboratory.. Adult male Sprague-Dawley rats.. A total of 210 rats had catheters placed with the proximal end buried subcutaneously. Rats were divided into three groups: tail vein bacterial injection on day 0 (no fibrin group) or on day 10 (fibrin group), or no injection/saline injection (control, n = 40). Bacterial injections were 1 x 108 colony forming units of either Staphylococcus epidermidis (n = 100) or Enterobacter cloacae (n = 60). Animals were killed 3 days after injection. Blood cultures were obtained via cardiac puncture, and catheters were removed via the chest. Half of the catheter was rolled onto agar and the other half was placed in trypticase soy broth. Plates and broth were incubated at 37 degrees C for 48 hrs. The presence of >15 colonies on roll plates, or growth in broth, was accepted as a positive sign of infection. Microscopy was performed on day 20-10 catheters. Thirty animals without catheters had bacterial injections and underwent blood culture 3 days after injection.. Catheter infection with S. epidermidis occurred in 32% of roll plates and 80% of broth from the fibrin group vs. 4% and 20% from the no fibrin group (p <.01 for each). Catheter infection with E. cloacae occurred in 50% of roll plates and 80% of broth from the fibrin group vs. 0% and 12% from the no fibrin group (p <.01 for each). Positive blood cultures occurred in 47 of 68 animals from the fibrin group vs. 8 of 68 from the no fibrin group (p <.01). Microscopy showed a fibrin sheath on 20 of 20 catheters. Without catheters, 30 of 30 blood cultures were negative.. The fibrin sheath significantly enhanced catheter-related infection and persistent bacteremia.

Topics: Animals; Bacterial Adhesion; Catheterization; Catheterization, Central Venous; Enterobacter cloacae; Equipment Contamination; Equipment Design; Fibrin; Male; Rats; Rats, Sprague-Dawley; Sepsis; Staphylococcus epidermidis

1Alpha,25-dihydroxyvitamin D3 (active form of vitamin D3; vitamin D3) has been reported to induce the upregulation of thrombomodulin and downregulation of tissue factor (TF) on monocytes. The possibility exists that vitamin D3 prevents the development of disseminated intravascular coagulation (DIC). In particular, monocyte TF production plays an important role in the pathophysiology of DIC in septic patients. We have attempted to determine whether vitamin D3 is effective against DIC in a rat model induced by lipopolysaccharides (LPS) (30 mg/kg, 4 h) or TF (3.75 U/kg, 4 h) using selective hemostatic parameters, markers of organ dysfunction and pathological findings (assessment of glomelular fibrin deposition). Vitamin D3 was administered orally each day at a dose of 2.0 mg/kg/day for 3 days, or low molecular weight heparin (LMWH 200 u/kg; i.v.) was given 10 min before the injection of TF or LPS in each treatment group. Vitamin D3 was effective against DIC in the rat model induced by LPS only, whereas LMWH was effective against DIC in both rat models induced by either TF or LPS. The anti-DIC effect of vitamin D3 was equal to (or more potent than) that of LMWH. The results suggested that vitamin D3 was useful for the treatment of LPS-induced DIC, and that the assessment of a drug's efficacy should be done carefully given the markedly different results obtained according to the agents used to induce DIC.

Topics: Administration, Oral; Animals; Anticoagulants; Cholecalciferol; Coagulants; Disease Models, Animal; Disseminated Intravascular Coagulation; Fibrin; Heparin; Kidney Diseases; Kidney Glomerulus; Lipopolysaccharides; Male; Rats; Rats, Wistar; Sepsis; Thromboplastin; Thrombosis

The impact of clot stability affecting the vasculopathy and tissue necrosis in Shwartzman reaction was investigated using plasma Factor XIII A2-depleted rabbit (FXIII-DR). Plasma Factor XIIIA2 (FXIIIA2) was depleted by infusion of the mono-specific goat anti-rabbit FXIIIA2 IgG. Generalized Shwartzman reaction (GSR) was induced by priming and challenged by i.v. injection of LPS and local Shwartzman reaction (LSR) was primed by intradermal injection of LPS and challenged by i.v. injection of LPS. Histological examination of the GSR animals showed, extensive thrombi accumulation in renal tubules and bilateral cortical necrosis of kidney in 8 out of 10 rabbits but none in the FXIII-DR. Fibrinogen levels were elevated to 3 approximately 4 fold at 24 h and lowered at 48 h whereas a steady rise was seen in the FXIII-DR. FDP levels in GSR animals were significantly elevated at 24 h and further increased at 48 h but only slightly elevated in the FXIII-DR. Examination of the LSR tissues after 48 h showed an acute onset of progressive cutaneous vascular thrombosis, purpura, and secondary hemorrhagic necrosis whereas neither fibrin deposit nor necrosis of tissue were detected in FXIII-DR despite of an early edema formation. Fibrinogen levels were also increased two fold at 24 h but returned to basal levels at 48 h in control LSR animals but not affected at all in FXIII-DR. These results suggest that during the severe inflammatory conditions such as sepsis, the fibrinolytic system is functionally sufficient to dissipate the pathogenic accumulation of disseminated intravascular clots and exudated fibrin clots if those clots were prevented from getting crosslinked in plasma.

Topics: Animals; Antibodies, Monoclonal; Disease Models, Animal; Disseminated Intravascular Coagulation; Factor XIII; Factor XIII Deficiency; Fibrin; Fibrinogen; Kidney; Kidney Diseases; Lipopolysaccharides; Necrosis; Plasminogen; Rabbits; Sepsis; Shwartzman Phenomenon; Skin; Skin Diseases

Mutations in the gene encoding thrombomodulin (TM), a thrombin regulator, are suspected risk factors for venous and arterial thrombotic disease. We have previously described the generation of TM(Pro/Pro) mice carrying a TM gene mutation that disrupts the TM-dependent activation of protein C. Here, it is shown that inbred C57BL/6J TM(Pro/Pro) mice exhibit a hypercoagulable state and an increased susceptibility to thrombosis and sepsis. Platelet thrombus growth after FeCl(3)-induced acute endothelial injury was accelerated in mutant mice. Vascular stasis after permanent ligation of the carotid artery precipitated thrombosis in mutant but not in normal mice. Mutant mice showed increased mortality after exposure to high doses of endotoxin and demonstrated altered cytokine production in response to low-dose endotoxin. The severity of the hypercoagulable state and chronic microvascular thrombosis caused by the TM(Pro) mutation is profoundly influenced by mouse strain-specific genetic differences between C57BL/6 and 129SvPas mice. These data demonstrate that in mice, TM is a physiologically relevant regulator of platelet- and coagulation-driven large-vessel thrombosis and modifies the response to endotoxin-induced inflammation. The phenotypic penetrance of the TM(Pro) mutation is determined by as-yet-uncharacterized genetic modifiers of thrombosis other than TM.

Topics: Animals; Blood Coagulation; Carotid Artery Thrombosis; Chlorides; Cytokines; Ferric Compounds; Fibrin; Genetic Predisposition to Disease; Ligation; Lipopolysaccharides; Mice; Mice, Inbred C57BL; Mice, Transgenic; Mutation; Sepsis; Survival Analysis; Thrombomodulin; Thrombosis

Although tissue factor (TF) is involved in hemostasis, thrombogenesis, inflammation, and cellular immune response, its source in sepsis remains controversial. Recently, we found that, in addition to monocytes and endothelial cells, neutrophils may express TF in a rabbit model. The purpose of this study was to determine whether neutrophils could be a source of TF in a monkey model of sepsis.. TF messenger RNA (mRNA) and protein in neutrophils were assayed by in situ hybridization and immunohistochemistry in tissues obtained from monkeys after injection of lipopolysaccharide (LPS) (n = 3) and after injection of saline as a control (n = 2). Coagulation parameters were measured before and at 1.5 and 3 hours after injections.. In LPS-treated monkeys, TF mRNA and protein were induced not only in monocytes and endothelial cells, but also in neutrophils accumulating in the liver 3 hours after LPS injection. Thrombin-antithrombin III complex and fibrin degradation products D-dimer levels were significantly increased at 3 and 1.5 hours after LPS injection compared with controls.. Neutrophils are a source of TF and are implicated in direct activation of the coagulation cascade in the early phases of sepsis in the monkey. These results give important information for the treatment of sepsis.

Topics: Animals; Antithrombin III; Escherichia coli; Fibrin; Fibrin Fibrinogen Degradation Products; Immunohistochemistry; In Situ Hybridization; Lipopolysaccharides; Liver; Lung; Macaca; Macaca mulatta; Male; Neutrophils; Peptide Hydrolases; RNA, Messenger; Sepsis; Thromboplastin

Topics: Acute Disease; Animals; Antithrombin III; Blood Coagulation Disorders; Complement Activation; Cytokines; Disseminated Intravascular Coagulation; Endotoxemia; Fibrin; Gene Expression Regulation; Hemorrhage; Humans; Lipoproteins; Lung Injury; Primates; Protein C; Reactive Oxygen Species; Respiratory Distress Syndrome; Sepsis; Thromboplastin; Transcription, Genetic; Tumor Necrosis Factor-alpha

The bleeding syndrome of acute promyelocytic leukemia (APL) is complex and consists of disseminated intravascular coagulation (DIC) and hyperfibrinolysis. Elastase, derived from malignant promyelocytes, is believed to mediate the fibrinogeno- and fibrinolysis by aspecific proteolysis. In this study we measured the role of elastase in fifteen patients with APL by using an assay for elastase degraded fibrin(ogen) and the results were compared with those obtained in patients with sepsis induced DIC. High levels of elastase were observed in sepsis and APL. The levels of fibrinogen and fibrin degradation products were significantly higher in APL patients compared to patients with sepsis induced DIC. Nevertheless, the level of elastase degraded fibrin(ogen) was higher in the sepsis group (635.3 ng/ml, compared to 144.3 ng/ml in APL; p <0.0001). So, the enormous increase in fibrin and fibrinogen degradation products in APL cannot be explained by elastase activity. This study suggests a minor role for elastase mediated proteolysis in the hemorrhagic diathesis in APL patients.

Topics: Adult; Aged; Aged, 80 and over; Antibodies, Monoclonal; Blood Coagulation Tests; Disease Susceptibility; Disseminated Intravascular Coagulation; Female; Fibrin; Fibrin Fibrinogen Degradation Products; Fibrinogen; Fibrinolysis; Hemorrhage; Humans; Leukemia, Promyelocytic, Acute; Male; Middle Aged; Neoplasm Proteins; Pancreatic Elastase; Sepsis

Extravascular coagulation and fibrin deposition coupled with perturbations of intravascular coagulation occurs in association with acute respiratory distress syndrome (ARDS). To evaluate the pathogenetic role of an extrinsic coagulation pathway in the intravascular coagulation of ARDS patients and to explore the time course of the changes of tissue factor levels, platelet counts, and disseminated intravascular coagulation (DIC), we performed a prospective cohort study.. The study subjects consisted of 113 patients: 27 patients with ARDS, 31 patients at risk for but not developing the syndrome, and 55 patients without ARDS. According to the underlying disease, the patients were further subdivided into two groups: patients with trauma (n = 76) and patients with sepsis (n = 37). Ten normal healthy volunteers served as control subjects. Plasma tissue factor antigen (tissue factor) levels and platelet counts were measured on the day of admission and on days 1 through 4 after admission. Simultaneously, the DIC scores were determined.. The values of tissue factor in the patients with ARDS were significantly more elevated than those measured in the other two groups (p < 0.001) and control subjects (p < 0.001) on the day of admission. The values continued to be markedly high up to day 4 of admission. On the day of admission, the platelet counts in the ARDS patients showed significantly lower values (p < 0.05) than those in the other two groups. The incidence of DIC and the DIC scores in ARDS patients were significantly higher than those in the other two groups. The tissue factor levels (r(s) = 0.428, p < 0.0001) and DIC scores (r(s) = 0.357, p < 0.0002) correlated significantly with Lung Injury Score. When the patients were subdivided into two subgroups, i.e., trauma and sepsis, some differences of the tissue factor levels were noted between the two groups.. We demonstrated that tissue-factor dependent coagulation pathway of plasma is extensively activated in patients with ARDS, followed by intravascular coagulation and platelet consumption. We further provide precise information on the time course of tissue factor levels and DIC in patients with ARDS and those at risk for developing this syndrome.

Topics: Analysis of Variance; APACHE; Blood Coagulation; Case-Control Studies; Disseminated Intravascular Coagulation; Female; Fibrin; Fibrinogen; Humans; Male; Middle Aged; Multiple Trauma; Platelet Count; Prospective Studies; Prothrombin Time; Respiratory Distress Syndrome; Risk Factors; Sepsis; Thromboplastin; Time Factors

Plasma fibronectin (Fn) can both enhance phagocytic clearance of microparticulate debris by macrophages as well as incorporate it into the lung extracellular matrix (ECM). The goal of this study was to document that N-ethylmaleimide (NEM)-treated human plasma Fn (HFn) would lose its ability to incorporate into the lung ECM in vivo even though it would retain its ability to stimulate test particle phagocytosis and bind to fibrin. Using dual-label immunofluorescence, we compared the lung deposition of purified normal HFn and NEM-alkylated HFn (NEM-HFn) after their intravenous injection into postoperative nonbacteremic and bacteremic sheep in relationship to the localization of endogenous sheep Fn. Two days after a sterile surgical thoracotomy, sheep were infused with either 5 x 10(8) Pseudomonas aeruginosa (postsurgical bacteremic model) or the diluent (nonbacteremic model). They also received a bolus 100-mg injection (5 min) of either HFn or NEM-HFn. Analysis of serial lung biopsies harvested at 2-h intervals demonstrated little deposition of NEM-HFn compared with HFn in the lung interstitial matrix of postoperative nonbacteremic sheep. In contrast, enhanced deposition of both HFn and NEM-HFn was observed in the lungs of postoperative bacteremic sheep. However, in the lungs of bacteremic sheep, HFn displayed a diffuse fibrillar deposition pattern in the lung characteristic of ECM incorporation, whereas the enhanced NEM-HFn deposition, especially in the interstitial ECM region of the lung, was primarily focal and punctate, with very little fibrillar incorporation. Immunofluorescent analysis with antibodies specific to fibrinogen, Fn, and lung macrophage surface antigens coupled with immunoperoxidase staining for HFn antigen revealed that the punctate fluorescence pattern was due to both the binding of HFn to fibrin and its colocalization with inflammatory cells. Thus treatment of plasma Fn with low concentrations of NEM will limit its normal in vivo fibrillar incorporation into the interstitial ECM region of the lung.

Topics: Alkylation; Animals; Ethylmaleimide; Extracellular Matrix; Fibrin; Fibronectins; Hemodynamics; Humans; Immunoenzyme Techniques; Lung; Postoperative Complications; Sepsis; Sheep

Plasma-soluble fibrin monomer (SFM) level in patients with disseminated intravascular coagulation (DIC) was significantly higher than the level in patients with pre-DIC or in non-DIC patients, and the level in patients with pre-DIC was significantly higher than that in non-DIC patients. There was no significant difference in plasma SFM levels among various diseases underlying DIC. Plasma SFM level in patients with good outcome was significantly decreased after treatment for DIC. The sensitivity of fibrin degradation products and platelet number was high for DIC, but not for pre-DIC. The sensitivity of thrombin-antithrombin III complex, plasmin-plasmin inhibitor complex, and SFM was high for both DIC and pre-DIC. The specificity of these markers was also high. Receiver operating characteristic analysis suggests that plasma SFM level could be the most useful marker for the diagnosis of both DIC and pre-DIC.

Topics: Amino Acid Sequence; Animals; Antibodies, Monoclonal; Blood Coagulation Tests; Disseminated Intravascular Coagulation; Enzyme-Linked Immunosorbent Assay; Fibrin; Fibrin Fibrinogen Degradation Products; Humans; Leukemia; Molecular Sequence Data; Neoplasms; Platelet Count; Prognosis; Retrospective Studies; Sensitivity and Specificity; Sepsis

To evaluate the role of disseminated intravascular coagulation (DIC) and to determine the influence of antithrombin, protein C, and plasminogen activator inhibitor 1 on multiple organ dysfunction syndrome (MODS) and outcome in patients with systemic inflammatory response syndrome (SIRS), we made a prospective cohort study. The study subjects consisted of thirty-five patients who exhibited two or more of the conditions of SIRS for more than three consecutive days. They were classified into subgroups of survivors (n = 13) and nonsurvivors (n = 22). The global coagulation and fibrinolytic markers, antithrombin, protein C, and plasminogen activator inhibitor 1 were measured on the day of the diagnosis of SIRS, and also on the 1st, 3rd, and 5th days. The results of these measurements, demographic data, criteria of severity, incidence of MODS were compared between the subgroups. For prediction of patient's death, a receiver operating characteristic (ROC) curve analysis was made. DIC was frequently associated with SIRS patients (29/35, 82.9%). A significant decrease in the DIC score was found in the survivors (p = 0.0001). None of them suffered from DIC on the 5th day. In the nonsurvivors, low levels of protein C and antithrombin and markedly high values of plasminogen activator inhibitor 1 continued up to the 5th day, no improvement of the DIC was observed during the study period and the number of the dysfunctioning organs were significantly higher than in the survivors. Plasminogen activator inhibitor 1 on the 5th day had prognostic value for the prediction of death on the SIRS patients. In conclusion, DIC occurs commonly in patients with SIRS and may be the main determinant for the outcome of these patients. Changes in antithrombin, protein C, and plasminogen activator inhibitor 1 are one of the aggravating factors of MODS. Furthermore, plasminogen activator inhibitor 1 is a good predictor of death in these patients.

Topics: Adult; Aged; Anticoagulants; APACHE; Biomarkers; Combined Modality Therapy; Disseminated Intravascular Coagulation; Female; Fibrin; Fibrinogen; Humans; Japan; Male; Middle Aged; Plasma; Plasminogen Activator Inhibitor 1; Platelet Count; Prospective Studies; ROC Curve; Sepsis; Survivors; Syndrome; Systemic Inflammatory Response Syndrome; Treatment Outcome

Various assays have been developed for quantitation of soluble fibrin or fibrin monomer in clinical plasma samples, since this parameter directly reflects in vivo thrombin action on fibrinogen. Using plasma samples from healthy blood donors, patients with cerebral ischemic insult, patients with septicemia, and patients with venous thrombosis, we compared two immunologic tests using monoclonal antibodies against fibrin-specific neo-epitopes, and two functional tests based on the cofactor activity of soluble fibrin complexes in tPA-induced plasminogen activation. Test A (Enzymun-Test FM) showed the best discriminating power among normal range and pathological samples. Test B (Fibrinostika soluble fibrin) clearly separated normal range from pathological samples, but failed to discriminate among samples from patients with low grade coagulation activation in septicemia, and massive activation in venous thrombosis. Functional test C (Fibrin monomer test Behring) displayed good discriminating power between normal and pathological range samples, and correlated with test A (r = 0.61), whereas assay D (Coa-Set Fibrin monomer) showed little discriminating power at values below 10 micrograms/ml and little correlation with other assays. Standardization of assays will require further characterization of analytes detected.

Topics: Antibodies, Monoclonal; Brain Ischemia; Enzyme Activation; Enzyme-Linked Immunosorbent Assay; Epitopes; Evaluation Studies as Topic; Fibrin; Humans; Plasminogen; Reagent Kits, Diagnostic; Sepsis; Solubility; Spectrophotometry; Thrombophlebitis

Reciprocal interactions between elements of the acute inflammatory response and the coagulation system play important roles in host defense homeostasis during Gram-negative bacterial sepsis. However, derangements in the regulation of the inflammatory-coagulant axis in this setting may result in progressive tissue damage and disseminated intravascular coagulation. In this article, the integrated responses in the baboon model of Escherichia coli sepsis are analyzed as a basis of understanding these response interactions in the critically ill. In particular, three topics will be reviewed. First, the role of tissue factor in mediating the coagulant response to inflammation and the role of tumor necrosis factor (TNF) in initiating and amplifying this coagulant response into a full-blown consumptive coagulopathy are defined. A second and parallel topic concerns the role played by tissue factor pathway inhibitor and other anticoagulant systems in not only regulating this coagulant response, but also in attenuating the initial inflammatory response. The third topic concerns the use of assays of enzyme inhibitor complexes composed of components of these regulatory anticoagulant systems to help define the hypercoagulable state and possibly to make an early, specific diagnosis of sepsis prior to overt failure of the hemostatic system.

Topics: Animals; Blood Coagulation; Blood Coagulation Factors; Disseminated Intravascular Coagulation; Endothelium, Vascular; Escherichia coli Infections; Fibrin; Inflammation; Lipoproteins; Papio; Sepsis; Thromboplastin; Tumor Necrosis Factor-alpha

Endopatch E-F is a new product elaborated with natural human and animal proteins. Its synthesis originates in a covalent link between elastin and fibrin monomers. Numerous experimental studies carried out in animal have previously shown its ability to reinforce healing process of digestive wall. The results reported herein have been obtained in very selected patients in whom a digestive anastomosis had to be done in spite of unfavorable circumstances, such as intra-abdominal infection, radiated bowel or ascitis. From October 1990 to October 1992, 21 digestive anastomosis have been performed in 18 patients. All were reinforced by Endopatch E-F. Two deaths have been observed (mortality: 11.1%), which do not look like a consequence of the use of the product (One myocardial infarction and one cirrhotic failure). There were 2 post-operative fistulas (9.5% of the whole anastomosis). No patients had any reaction of intolerance. These preliminary results confirm experimental data, and suggest that Endopatch EF can be used in order to reinforce digestive sutures when performed under unfavorable circumstances.

Topics: Adult; Aged; Aged, 80 and over; Biocompatible Materials; Elastin; Female; Fibrin; Humans; Male; Middle Aged; Postoperative Complications; Sepsis; Sutures; Wound Healing

Elevated levels of soluble fibrin in plasma indicate that thrombin converts fibrinogen to fibrin without sufficient inhibitory control. Therefore, measurement of soluble fibrin (SF) in plasma may be considered as a laboratory test for intravascular coagulation. We have demonstrated that a new immunoassay for detection of SF in human plasma (Lill et al., Blood Coag Fibrinol 1993; 4: 97-102), based on a fibrin specific monoclonal antibody, also detects porcine SF with high sensitivity. Thrombin-dependent generation of SF in porcine plasma in vitro resulted in increased reactivity of the assay system, which was time and dose dependent. Dextran sulphate (DXS) and bacterial lipopolysaccharide (LPS) were used as stimuli in in vivo experiments in pigs. Plasma levels of SF increased steadily after intravenous administration of DXS (5 mg/kg for 1 h) to 38 +/- 7.8 micrograms/ml (mean +/- SEM) at 2 h, whereas LPS (2 micrograms/kg/h for 6 h) markedly increased plasma SF levels to over 120 micrograms/ml (at 6 h) after a lag phase of 2 h. In conclusion, this new immunoassay for human fibrin allows specific and sensitive detection of soluble fibrin in porcine plasma.

Topics: Animals; Antibodies, Monoclonal; Blood Coagulation; Dextran Sulfate; Disease Models, Animal; Disseminated Intravascular Coagulation; Fibrin; Immunoassay; Lipopolysaccharides; Sepsis; Swine

It has been experimentally shown that endotoxin induces a marked increase in the levels of a fast-acting inhibitor of plasminogen activator (PAI). The plasma PAI activity and tissue-type plasminogen activator (t-PA) concentrations were measured in 61 patients with human septicaemia and results were compared with those observed in healthy controls. There was a markedly significant increase of PAI in plasma and platelet extracts of patients with septicaemia as compared to controls (p less than 0.0001). No correlation between PAI and endotoxin concentration was observed. Fibrin autography of plasma samples confirmed that activator inhibition was associated with the formation of an enzyme-inhibitor complex. t-PA activity was similar in patients and controls, whereas t-PA Ag showed a significant increase in patients (p less than 0.0001). A significant inverse correlation between t-PA activity and PAI was observed (p less than 0.05). PAI activity was higher in patients with positive blood cultures (p less than 0.0001) and gram-negative septicaemia (p less than 0.0001). There was also a significant increase of PAI levels in patients with disseminated intravascular coagulation (DIC) as compared with patients without DIC (p less than 0.001). We conclude that there is a marked increase of PAI in patients with sepsis. Increased PAI activity may contribute to the pathogenesis of DIC associated with septicaemia.

Topics: Adolescent; Adult; Aged; Blood Specimen Collection; Disseminated Intravascular Coagulation; Electrophoresis, Polyacrylamide Gel; Endotoxins; Female; Fibrin; Glycoproteins; Humans; Male; Middle Aged; Plasminogen Activators; Plasminogen Inactivators; Sepsis; Tissue Plasminogen Activator

The adhesion to fibrin-platelet clots in vitro of 21 strains of streptococci isolated from the blood of patients with sub-acute bacterial endocarditis (SABE) was measured. The species, in order of greatest adhesion, were Streptococcus faecalis, Streptococcus mutans, Streptococcus milleri, Streptococcus sanguis, dextran-positive Streptococcus mitior, dextran-negative Streptococcus mitior and Streptococcus salivarius. Individual strains within species, however, cannot be assumed to be representative of their species and may exhibit unusually high or low adhesion. Adhesion depended upon both bacterial concentration and period of contact. There was no simple relationship between ability to adhere and liability to cause endocarditis. Formation of dextran did not increase adhesion. The streptococci were more adhesive than strains of Escherichia coli and Neisseria sicca and less adhesive than strains of Staphylococcus aureus and Streptococcus pyogenes.

Topics: Adhesiveness; Blood Coagulation; Blood Platelets; Dextrans; Endocarditis, Subacute Bacterial; Enterococcus faecalis; Escherichia coli; Fibrin; Humans; Neisseria; Sepsis; Staphylococcus aureus; Streptococcal Infections; Streptococcus; Streptococcus mutans; Streptococcus pyogenes; Streptococcus sanguis

This article deals with the clinical importance of antithrombin III (AT III) in renal disease. Patients with nephrotic syndrome demonstrates a high risk of thromboembolism. A renal AT III loss is an important pathogenetic factor in these events. Patients with serumalbumin below 2.0 g/dl are mostly endangered. In patients with acute oligoanuric renal failure low AT III-levels due to consumption were often found that lead to diminished protection against intravascular coagulation processes and can therefore contribute to progression of illness. An AT III-substitution may be of some benefit in these patients. Additionally AT III was given in patients with dialysis-dependent renal failure and low levels of AT III leading to a reduced incidence of thrombosis of the extracorporeal system. Unnecessary high doses were also avoided and a minimal heparinization could be performed more efficiently in bleeding risk patients. Furthermore, AT III-levels during renal transplantation and during organ rejection are reported.

Topics: Acute Kidney Injury; Antithrombin III; Antithrombin III Deficiency; Female; Fibrin; Humans; Kidney Diseases; Nephrotic Syndrome; Pregnancy; Puerperal Disorders; Risk; Sepsis; Thromboembolism; Thrombosis

Topics: alpha 1-Antitrypsin; Antithrombin III; Blood Proteins; Factor XIII; Fibrin; Humans; Lysosomes; Neutrophils; Pancreatic Elastase; Peptide Hydrolases; Protease Inhibitors; Sepsis

Infectious endocarditis (IE) develops following bacteremic episodes during which bacteria may attach to sterile thrombotic vegetations. Such thrombotic vegetations result from the deposition of platelets and fibrin on lesioned endothelium. These sterile vegetations are the most susceptible to infection in the left side of the heart, since this localization is found in as much as 80% of the patients with IE. Any circulating bacterial or mycotic organism may induce endocarditis, but streptococci are most often responsible, possibly because of their high capacity to adhere to thrombotic vegetations. The host cell defenses apparently cannot penetrate the dense network of platelet and fibrin in the vegetation, and humoral immunity (antibodies and complement) are of no help against gram-positive cocci. Thus, the infected vegetation has been compared to a localized agranulocytic focus, permitting the survival of infection and allowing bacteria to be released freely and continuously into the circulation (hence the constant bacteremia, a hallmark of IE). In the subacute and chronic evolution of IE, the clinical findings are mainly due to immunization of the host against the infecting microbe, resulting in antigen-antibody-complex-mediated vasculitis, and in nonspecific symptoms. Only positive blood cultures at this stage will confirm the clinical suspicion of endocarditis. Embolism may occur in any organ and falsify the diagnosis because of focal signs. Local complications of IE are the major cause of mortality in this disease, and are due to valve perforation, paravalvular abscesses, cardiac metastatic abscesses etc. If these complications occur early in the course of IE, the course may be acute.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Agranulocytosis; Endocarditis, Bacterial; Endocarditis, Subacute Bacterial; Fibrin; Humans; Platelet Aggregation; Sepsis; Streptococcal Infections; Streptococcus

Injection of approximately 10(6) to 10(9) Escherichia coli into the renal arteries of rabbits resulted in retention of sufficient numbers of organisms in renal vessels to permit study of the mechanism of localization by electron microscopy. After injection of the bacterial suspension, perfusion fixation was used to maintain open vascular contours. Individual organisms were found to adhere to the endothelium of glomerular and intertubular capillaries, and ruthenium red staining demonstrated a close interaction between the largely polysaccharide bacterial microcapsule and the sialoglycoprotein endothelial surface coat. Thus, individual E. coli seem to localize in the rabbit kidney in this model by sticking to the endothelial surfact coat of the renal vessels. After localization, polymorphonuclear leukocytes and monocytes appeared in the capillaries and phagocytosed the bacteria. Phagocytosis of bacteria was evident at 10 minutes and was almost complete at 60 minutes and, although less frequent, were associated with small amounts of fibrin at 60 minutes. This acute inflammation and thrombosis may be mediated by activation of complement through the alternate pathway.

Topics: Acute Disease; Animals; Capillaries; Cell Membrane; Escherichia coli; Female; Fibrin; Kidney Glomerulus; Macrophages; Neutrophils; Phagocytosis; Platelet Aggregation; Pyelonephritis; Rabbits; Sepsis

In previous studies we have presented morphological evidence that the terminal shock-like phase of fatal meningococcemia is caused by the occlusion of the pulmonary microcirculation with thrombi composed of platelets, leukocytes, and fibrin. We have also shown that in experimental meningococcemia, pretreatment of rabbits with heparin sodium prevents fibrin formation but does not influence the cellular pulmonary thrombi and does not prolong survival. If our theory is correct, drugs that inhibit platelet aggregation and leukocyte adhesion in rabbits should prolong life. The present experiment demonstrates that pretreatment with a small dose of aspirin doubles the survival time without altering the mortality.

Topics: Animals; Aspirin; Female; Fibrin; Kidney Glomerulus; Kidney Tubular Necrosis, Acute; Lung; Meningococcal Infections; Rabbits; Sepsis; Shock, Septic

Ninety-three postoperative patients 1 day to 13 years of age had blood cultures, limulus lysate assay, determination of fibrin degradation products, white blood cell and platelet counts. Seven groups were studied. The limulus lysate assay was often positive (64%) in the presence of gram negative septicemia but there were false positives and negatives. The tests for fibrin degradation products were inconsistent. The white blood cell count was low in babies with gram negative septicemia. One hundred per cent of the infants with gram negative septicemia had a platelet count below 150,000; 71% below 100,000 (average 67,000 septic babies, 257,000 non-septic babies). The drop in platelet count with gram negative septicemia was abrupt---as much as 222,000 in 24 hours. Platelets increased when therapy was effective. Two children with gram negative septicemia had platelet counts of 50,000 and 20,000. The platelet count for patients with gram positive septicemia was 299,000, and above 150,000 in all children with ruptured and non-ruptured appendicitis and major surgery without gram negative septicemia. It was concluded that serial measurements of platelet count in the postoperative infant and child was a rapid and reliable method for early detection of gram negative septicemia and changes in platelet count in response to treatment was an indicator of the effectiveness of therapy.

Topics: Abdominal Muscles; Adolescent; Appendicitis; Bacteria; Bacterial Infections; Blood Cell Count; Blood Platelets; Child; Child, Preschool; Enterocolitis, Pseudomembranous; Escherichia coli Infections; Fibrin; Gangrene; Humans; Infant; Infant, Newborn; Intestinal Obstruction; Klebsiella Infections; Leukocyte Count; Liver Neoplasms; Platelet Aggregation; Postoperative Complications; Pseudomonas Infections; Sepsis; Time Factors

Topics: Anti-Inflammatory Agents; Candida albicans; Dipyridamole; Drug Synergism; Endotoxins; Erythrocyte Aggregation; Fibrin; Fibrinogen; Fibrinolytic Agents; Heparin; Humans; Infant; Male; Pseudomonas aeruginosa; Sepsis

Bacterial and fungal growth in 10% soybean oil emulsion (Intralipid) and 5% fibrin hydrolysate in 5% dextrose was studied at 4, 25 and 37 degrees C. Staphylococcus aureus, Streptococcus pyogenes, Str. fecalis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli and Candida albicans were grown in broth at 37 degrees C, diluted in saline and inoculated into each of the two preparations as well as a mixture of the two. Growth was measured at 24, 48 and 72 hours. In 10% soybean emulsion, all bacteria except S. pyogenes multiplied, but in fibrin hydrolysate-dextrose solution the only organism of those studied to grow was S. aureus. In the hydrolysate-dextrose-lipid mixture, all organisms multiplied except S. pyogenes and P. aeruginosa. C. albicans grew in all solutions tested. While at 4 degrees C, organisms did not multiply. The fibrin hydrolysate-dextrose solutions given by infusion into a central vein for hyperalimentation have been shown to support predominantly fungal growth, and contamination of the solution and ultimately of the indwelling catheter is a constant hazard. Because both bacteria and C. albicans grew equally well in 10% soybean oil emulsion, its use as a caloric source when infused into a central vein may increase the occurrence of sepsis. When this emulsion is used to provide essential fatty acids or calories, it should be given via a peripheral vein, so that a central catheter will not be contaminated.

Topics: Bacteria; Candida albicans; Fat Emulsions, Intravenous; Fibrin; Glucose; Humans; Parenteral Nutrition, Total; Risk; Sepsis

Topics: Adult; Animals; Blood Urea Nitrogen; Creatinine; Disseminated Intravascular Coagulation; Female; Fibrin; Glomerulonephritis; Humans; Hyalin; Kidney; Kidney Glomerulus; Lung; Male; Middle Aged; Pneumococcal Infections; Pneumonia, Pneumococcal; Proteinuria; Rats; Sepsis; Streptococcus pneumoniae; Thrombosis; Uremia

Topics: Blood Coagulation Tests; Carbon Radioisotopes; Carcinoma; Caseins; Disseminated Intravascular Coagulation; Electrophoresis; Esters; Factor XIII; Fibrin; Fibrinogen; Glycine; Hemagglutination Inhibition Tests; Humans; Leukemia; Sepsis; Serum Globulins; Solubility; Thrombocytopenia

Topics: Aged; Arthritis, Rheumatoid; Blood Cell Count; Blood Platelets; Carbon Radioisotopes; Collagen Diseases; Factor XIII; Female; Fibrin; Fibrinolysis; Heart Failure; Humans; Hypertension, Malignant; Infections; Leukemia; Liver Diseases; Neoplasms; Pulmonary Embolism; Sepsis; Streptokinase

Topics: Blood Coagulation Tests; Child; Child, Preschool; Disseminated Intravascular Coagulation; Factor V; Factor VIII; Fibrin; Fibrinogen; Hemolytic-Uremic Syndrome; Humans; Infant; Prothrombin Time; Sepsis

Topics: Afibrinogenemia; Aneurysm; Bacteria; Blood Coagulation; Blood Coagulation Tests; Blood Platelets; Diagnosis, Differential; Disseminated Intravascular Coagulation; Enzyme Activation; Fibrin; Fibrinogen; Fibrinolysis; Hemostasis; Heparin; Models, Biological; Prothrombin; Sepsis; Shwartzman Phenomenon; Thrombin; Thromboplastin

Topics: Adolescent; Adult; Aged; Bacterial Infections; Blood Cell Count; Blood Coagulation Factors; Blood Coagulation Tests; Blood Platelets; Child; Female; Fibrin; Fibrinogen; Humans; Male; Methods; Middle Aged; Mycoplasma Infections; Sepsis; Virus Diseases

Topics: Blood Cell Count; Blood Platelets; Child; Child, Preschool; Female; Fibrin; Fibrinogen; Fibrinolysis; Humans; Infant; Male; Meningitis; Meningococcal Infections; Neisseria meningitidis; Sepsis; Thrombocytopenia

Eight patients with E. coli septicaemia had oliguric renal failure which was associated with haematological evidence of intravascular coagulation. Five of these patients also had the characteristic blood picture of microangiopathic haemolytic anaemia. In an attempt to prevent further deposition of fibrin, intravenous heparin was administered to six patients, three of whom recovered fully and three died. The diagnosis of intravascular coagulation was subsequently confirmed by histological examination of necropsy material and it is suggested that some of the complications of E. coli septicaemia may be attributable to disseminated intravascular coagulation.

Topics: Anemia, Hemolytic; Autopsy; Blood Coagulation Tests; Blood Platelets; Disseminated Intravascular Coagulation; Erythrocyte Count; Escherichia coli Infections; Female; Fibrin; Hemoglobinometry; Heparin; Humans; Infant, Newborn; Injections, Intravenous; Leukocyte Count; Male; Middle Aged; Reticulocytes; Sepsis; Urea

Topics: Blood Glucose; Blood Urea Nitrogen; Body Weight; Caseins; Catheterization; Cholesterol; Dietary Carbohydrates; Emulsions; Esophagitis; Fibrin; Gastrointestinal Diseases; Hemoglobins; Humans; Insulin; Lipids; Liver; Liver Function Tests; Nutritional Requirements; Parenteral Nutrition; Protein Hydrolysates; Sepsis; Staphylococcal Infections; Triglycerides

Topics: Blood Coagulation Disorders; Child, Preschool; Disseminated Intravascular Coagulation; Fibrin; Heparin; Humans; Male; Meningococcal Infections; Prognosis; Sepsis

Topics: Adolescent; Adult; Aged; Anti-Bacterial Agents; Bacteria; Blood Cell Count; Blood Coagulation; Blood Platelets; Drainage; Female; Fibrin; Fibrinogen; Fibrinolysis; Humans; Male; Middle Aged; Plasminogen; Sepsis; Time Factors

Topics: Aged; Angiography; Antigens; Female; Femoral Neck Fractures; Fibrin; Fibrinogen; Fibrinolysis; Heart Failure; Humans; Iodine Radioisotopes; Male; Neoplasm Metastasis; Postoperative Complications; Pulmonary Embolism; Radionuclide Imaging; Sepsis; Thrombophlebitis

Topics: Animals; Blood Platelets; Blood Protein Electrophoresis; Disseminated Intravascular Coagulation; Dogs; Erythrocytes; Escherichia coli Infections; Fibrin; Fibrinolysis; Lipoproteins; Lung; Microcirculation; Neutrophils; Pulmonary Circulation; Sepsis; Thromboembolism; Time Factors; Triglycerides

Topics: Anuria; Disseminated Intravascular Coagulation; Escherichia coli Infections; Fibrin; Humans; Kidney Failure, Chronic; Sepsis

Topics: Appendectomy; Autopsy; Cachexia; Chemical Precipitation; Fibrin; Humans; Intracranial Pressure; Ischemia; Lymphatic System; Sepsis; Shwartzman Phenomenon; Spleen

Topics: Acute Kidney Injury; Disseminated Intravascular Coagulation; Female; Fibrin; Glomerulonephritis; Heparin; Kidney Diseases; Nephritis, Interstitial; Pregnancy; Pregnancy Complications, Infectious; Sepsis

Topics: Animals; Blood; Cardiac Catheterization; Endocarditis, Bacterial; Fibrin; Injections, Intravenous; Rabbits; Sepsis; Streptococcus; Time Factors

Counterelectrophoresis using a discontinuous buffer system permits detection of fibrinogen-fibrin degradation products (FDP) under a variety of clinical circumstances. The method is sensitive, reliable, and is easily performed using conventional equipment in any clinical laboratory assuming the responsibility for assaying fibrinogen-fibrin degradation products.

Topics: Blood Coagulation Tests; Contraceptives, Oral; Female; Fibrin; Fibrinogen; Humans; Immunoelectrophoresis; Liver Cirrhosis; Methods; Neoplasms; Postoperative Complications; Precipitin Tests; Sepsis; Thrombin

Topics: Animals; Blood Vessels; Endothelium; Endotoxins; Fibrin; Heparin; Leukocytes; Microscopy, Electron; Platelet Adhesiveness; Rabbits; Sepsis; Shock, Septic; Vascular Diseases

Topics: Abortion, Septic; Blood Coagulation Disorders; Disseminated Intravascular Coagulation; Ethanol; Female; Fibrin; Hematoma; Humans; Leukemia; Liver Cirrhosis; Methods; Neoplasms; Phlebitis; Postpartum Hemorrhage; Pregnancy; Pregnancy Complications, Hematologic; Sepsis

Topics: Blood Vessels; Diphtheria; Fibrin; Granulomatosis with Polyangiitis; Humans; Hypertension, Malignant; Lupus Erythematosus, Systemic; Necrosis; Polyarteritis Nodosa; Pyelonephritis; Rheumatic Fever; Sepsis; Splenic Artery; Tuberculosis, Meningeal; Vascular Diseases

Topics: Antigens; Blood Cell Count; Blood Coagulation; Blood Coagulation Disorders; Blood Coagulation Factors; Blood Coagulation Tests; Blood Platelets; Disseminated Intravascular Coagulation; Fibrin; Hemostasis; Humans; Meningococcal Infections; Sepsis; Thrombin

Topics: Abortion, Septic; Adolescent; Adult; Anticoagulants; Antithrombins; Blood; Blood Coagulation Disorders; Blood Coagulation Factors; Child; Disseminated Intravascular Coagulation; Encephalitis; Encephalitis Viruses; Female; Fibrin; Fibrinogen; Fibrinolysis; Hemorrhagic Disorders; Humans; Liver; Male; Necrosis; Pituitary Gland; Pregnancy; Prostatic Neoplasms; Prothrombin; Sepsis; Shock, Septic; Spleen; Streptokinase

Topics: Animals; Cardiac Surgical Procedures; Dogs; Fibrin; Heart Valve Prosthesis; Mitral Valve; Polymers; Postoperative Care; Postoperative Complications; Preoperative Care; Sepsis; Silicones

Topics: Animals; Blood Coagulation Disorders; Blood Platelets; Busulfan; Fibrin; Fibrinogen; Hemolysis; Injections, Intravenous; Kidney Glomerulus; Models, Biological; Neoplasms; Platelet Adhesiveness; Purpura; Rabbits; Sepsis; Shock; Shwartzman Phenomenon; Sulfonic Acids; Thrombocytopenia

Topics: Adolescent; Adult; Cadaver; Female; Fibrin; Humans; Immunosuppressive Agents; Kidney; Kidney Glomerulus; Kidney Transplantation; Male; Renal Dialysis; Sepsis; Shwartzman Phenomenon; Toxemia; Transplantation Immunology; Transplantation, Homologous

Topics: Adolescent; Adult; Blood Coagulation Disorders; Blood Coagulation Factors; Extraembryonic Membranes; Female; Fibrin; Fibrinolysis; Heparin; Humans; Kidney; Liver Cirrhosis; Middle Aged; Mononuclear Phagocyte System; Obstetric Labor, Premature; Pituitary Gland; Pregnancy; Sepsis; Shwartzman Phenomenon; Thrombin

Topics: Blood Coagulation; Capillaries; Endotoxins; Fibrin; Kidney Glomerulus; Pathology; Pseudomonas; Sepsis; Shwartzman Phenomenon

Topics: Animals; Electrons; Female; Fibrin; Glomerulonephritis; Humans; Kidney Diseases; Kidney Glomerulus; Microscopy; Microscopy, Electron; Pathology; Phagocytosis; Pre-Eclampsia; Pregnancy; Rabbits; Research; Sepsis; Thromboplastin