Disseminated intravascular coagulation (DIC): an approach

COVID-19 mortality prediction using ensemble learning and grey wolf optimization

COVID-19 is now often moderate and self-recovering, but in a significant proportion of individuals, it is severe and deadly. Determining whether individuals are at high risk for serious disease or death is crucial for making appropriate treatment decisions. We propose a computational method to estimate the mortality risk for patients with COVID-19. To develop the model, 4,711 reported cases confirmed as SARS-CoV-2 infections were used for model development. Our computational method was developed using ensemble learning in combination with a genetic algorithm. The best-performing ensemble model achieves an AUCROC (area under the receiver operating characteristic curve) value of 0.7802. The best ensemble model was developed using only 10 features, which means it requires less medical information so that the diagnostic cost may be reduced while the prognostic time may be improved. The results demonstrate the robustness of the used method as well as the efficiency of the combination of machine learning and genetic algorithms in developing the ensemble model.

Persistent disseminated intravascular coagulation despite correction of endoleaks after thoracoabdominal endovascular aneurysm repair

Disseminated intravascular coagulation (DIC) is a rare complication of endovascular aortic repair, commonly associated with type I or type III endoleaks. DIC is also known as consumption coagulopathy because excessive thrombin formation and secondary fibrinolysis leads to consumption of coagulation factors with hyperfibrinolysis and activation of platelets, which can lead to excessive bleeding. We present the case of an 80-year-old woman who had undergone thoracic endovascular aortic repair for a type B aortic dissection that was complicated by a series of recurrent endoleak-induced DICs requiring multiple thoracic endovascular aortic repair extensions to cover the entire thoracoabdominal aorta. The DIC persisted despite the resolution of the endoleaks.

Coagulopathy in SARS-CoV-2 Infected Patients: Implication for the Management of COVID-19

COVID-19 disease has led to an extraordinary inclusive health crisis globally. Elevation of D-dimer is the major remarkable abnormal coagulation test in seriously ill COVID-19 patients. In nearly 50% of COVID-19 patients, the value of D-dimer was significantly enhancing. Recent literature indicated that COVID-19 patients were at higher risk of developing disseminated intravascular coagulation. Pro-inflammatory cytokines and chemokines are some of the factors leading to these conditions. The majority of COVID-19 patients showed a higher profile of pro-inflammatory cytokines and chemokines in severe clinical conditions. Tumor necrosis factor-α (TNF-α) and interleukins (ILs) elevated in COVID-19 infected patients. TNF-α, IL-6, and IL-1 are major cytokines vital for the inhibition of intrinsic anticoagulant pathways. COVID-19 becomes a higher complication with a significant effect on blood cell production and hemostasis cascades. Deep vein thrombosis and arterial thrombosis are common complications. Changes in hematological parameters are also frequently observed in COVID-19 patients. Especially, thrombocytopenia is an indicator for poor prognosis of the disease and is highly expected and aggravates the likelihood of death of SARS-CoV-2 infected individuals. Thrombopoiesis reduction in COVID-19 patients might be due to viral abuse of the bone marrow/the viral load may affect thrombopoietin production and function. In other ways, immune-inflammation-mediated destruction and increased consumption of platelets are also the possible proposed mechanisms for thrombocytopenia. Therefore, the counting of platelet cells is an easily accessible biomarker for disease monitoring. All SARS-CoV-2 infected patients should be admitted and identifying potential higher-risk patients. It is also obligatory to provide appropriate treatments with intensive care and strict follow-up. In addition, considerations of chronic diseases are essential for better prognosis and recovery. The current review discusses coagulopathy among SARS-CoV-2 infected individuals and its complication for the management of the disease.

Disseminated intravascular coagulation: new identity as endotheliopathy-associated vascular microthrombotic disease based on in vivo hemostasis and endothelial molecular pathogenesis

Disseminated intravascular coagulation (DIC) can be correctly redefined as disseminated intravascular microthrombosis based on "two-path unifying theory" of in vivo hemostasis. "DIC" is a form of vascular microthrombotic disease characterized by "microthrombi" composed of platelets and unusually large von Willebrand factor multimers (ULVWF). Microthrombotic disease includes not only "DIC", but also microthrombosis occurring in thrombotic thrombocytopenic purpura (TTP), TTP-like syndrome, and focal, multifocal and localized microthrombosis. Being a hemostatic disease, microthrombotic disease occurs as a result of lone activation of ULVWF path via partial in vivo hemostasis. In endothelial injury associated with critical illnesses such as sepsis, the vascular damage is limited to the endothelial cell and activates ULVWF path. In contrast, in intravascular traumatic injury, the local damage may extend from the endothelial cell to subendothelial tissue and sometimes beyond, and activates both ULVWF and tissue factor (TF) paths. When endotheliopathy triggers exocytosis of ULVWF and recruits platelets, ULVWF path is activated and promotes microthrombogenesis to produce microthrombi composed of microthrombi strings, but when localized vascular damage causes endothelial and subendothelial tissue damage, both ULVWF and TF paths are activated and promote macrothrombogenesis to produce macrothrombus made of complete "blood clots". Currently, "DIC" concept is ascribed to activated TF path leading to fibrin clots. Instead, it should be correctly redefined as microthrombosis caused by activation of ULVWF path, leading to endotheliopathy-associated microthrombosis. The correct term for acute "DIC" is disseminated microthrombosis-associated hepatic coagulopathy, and that for chronic "DIC" is disseminated microthrombosis without hepatic coagulopathy. TTP-like syndrome is hematologic phenotype of endotheliopathy-associated microthrombosis. This correct concept of "DIC" is identified from novel theory of "in vivo hemostasis", which now can solve every mystery associated with "DIC" and other associated thrombotic disorders. Thus, sepsis-associated coagulopathy is not "DIC", but is endotheliopathy-associated vascular microthrombotic disease.

Peripheral serotonin causes dengue virus-induced thrombocytopenia through 5HT2 receptors

Dengue virus (DENV) is the most prevalent vector-borne viral pathogen, infecting millions of patients annually. Thrombocytopenia, a reduction in circulating platelet counts, is the most consistent sign of DENV-induced disease, independent of disease severity. However, the mechanisms leading to DENV-induced thrombocytopenia are unknown. Here, we show that thrombocytopenia is caused by serotonin derived from mast cells (MCs), which are immune cells that are present in the perivascular space and are a major peripheral source of serotonin. We show that during DENV infection, MCs release serotonin, which prompts platelet activation, aggregation, and enhanced phagocytosis, dependent on 5HT_2A receptors. MC deficiency in mice or pharmacologic inhibition of MCs reversed thrombocytopenia. Furthermore, reconstitution of MC-deficient mice with wild-type MCs, but not MCs lacking serotonin synthesis resulting from deficiency in the enzyme tryptophan hydroxylase-1, restored the thrombocytopenic phenotype. Exogenous serotonin was also sufficient to overcome the effects of drugs that inhibit platelet activation in vitro and to restore thrombocytopenia in DENV-infected MC-deficient mice. Therapeutic targeting of 5HT_2A receptors during DENV infection effectively prevented thrombocytopenia in mice. Similarly, serotonin derived from DENV-activated human MCs led to increased human platelet activation. Thus, MC-derived serotonin is a previously unidentified mechanism of DENV-induced thrombocytopenia and a potential therapeutic target.

Coagulation Disorders in Patients with Tumors of the Uterus

Sixty-eight previously untreated female subjects were studied: 26 patients with cervical carcinoma, 22 with endometrial carcinoma, and 20 with benign uterine diseases. These patients, together with 25 healthy female control subjects, underwent several coagulation tests, including beta-thromboglobulin (beta-TG) and platelet factor 4 (PF4) plasma levels. Of all the parameters considered, the variations in beta-TG and PF4 were the most interesting. They were increased in patients with cervical and endometrial carcinoma. The sensitivity of the two tests reached 79% (15/19) for patients with invasive cervical carcinoma and 74% (16/22) for all patients with endometrial carcinoma. Our data demonstrate that among the investigated parameters beta-TG and PF4 are the earliest disorders of the hemostatic system and are more frequently increased in the gynecologic malignancies.

Alveolar Hemorrhage

Alveolar hemorrhage (AH) is a clinical syndrome with diverse etiologies both immune and nonimmune. The defining pathological feature of AH is the presence or absence of pulmonary capillaritis. The antineutrophil cytoplasmic antibody (ANCA) related vasculitis and systemic lupus erythematosus are the commonest causes of immune AH with pulmonary capillaritis, whereas Goodpasture's syndrome and idiopathic pulmonary hemosiderosis are common causes of immune AH without pulmonary capillaritis. The major nonimmune causes of AH are primarily drug induced, or due to hematological malignancy and disorders of coagulation. Clinical features of AH include: dyspnea, fever, hemotypsis, bilateral crackles and pallor. Hypoxemia and bilateral diffuse airspace disease on the chest radiograph with relative sparing of the bases and apices which most often clears within 48 hours after its onset further characterize this syndrome. The major clinical implications of this syndrome are its potential to cause respiratory failure in severe cases and its sequelae of pulmonary fibrosis with associated morbidity and disability. In addition, AH may be the initial manifestation of a systemic immune disorder which can be managed optimally if recognized early. The diagnosis of AH is confirmed by bronchoalveolar lavage by demonstrating a progressively bloody return on successive aliquots of instilled saline or hemosiderin laden macrophages in the bronchoalveolar lavage fluid. The open lung biopsy remains the gold standard for the diagnosis of AH but is reserved for inapparent cases in whom corticosteroids and immunosuppressive therapy may be life saving. Serologic testing and examination of the urine sediment are useful adjuncts to the diagnosis. The treatment of AH is primarily supportive while an attempt is made to determine its etiology and initiate specific therapy. Glucocorticoids and cyclophosphamide are the cornerstones of therapy in immune AH with adjunctive plasmapheresis in life-threatening cases.

Disseminated intravascular coagulation: testing and diagnosis

Abnormalities of the hemostatic system in patients with DIC result from the sum of vectors for hypercoagulation and hyperfibrinolysis. DIC is classified into hyperfibrinolysis, hypercoagulation, massive bleeding or nonsymptomatic types according to the balance of the two vectors. Both the antithrombin (AT) and protein C (PC) levels are significantly low in patients with septic DIC, and reduced amounts of AT and PC result in the lack of inhibition of thrombin and activated FVIII, respectively. Thrombin activates FVIII, while activated FVIII accelerates the coagulation pathway to generate thrombin; thus activation of the coagulation system persists. Three sets of diagnostic criteria have been established by the Japanese Ministry of Health, Labour and Welfare, International Society of Thrombosis and Haemostasis and Japanese Association for Acute Medicine, respectively. Although these three diagnostic criteria score hemostatic abnormalities using similar global coagulation tests, the sensitivity and/or specificity for death differ. Treatment with AT or activated PC may not improve the outcomes of patients with sepsis at the early stage, although they may improve the outcomes in those with DIC. Therefore, new diagnostic criteria for determining the appropriate time to initiate anticoagulant treatment are required.

Successful renal transplantation from a brain-dead deceased donor with head injury, disseminated intravascular coagulation and deranged renal functions

Deceased donors (DDs) with the brain death due to head injury are the major source of organs for transplantation. The incidence of post-head injury disseminated intravascular coagulation (DIC) ranges from 24% to 50%. Many centers do not accept organs from donors with DIC due to increased risk of primary graft non-function and/or high chances of morbidity/mortality. We performed two successful renal transplants from a DD with head injury with DIC and deranged renal function. One of the recipients developed transient thrombocytopenia, but there was no evidence of DIC or delayed graft functions in either of the recipients. Over a follow-up of 1 month, both are doing well with stable graft function and hematological profile. Thus, a carefully selected DD with severe DIC even with deranged renal function is not a contraindication for organ donation if other risk factors for primary non-function are excluded. This approach will also help in overcoming organ shortage.

Diagnostic criteria and laboratory tests for disseminated intravascular coagulation

Three diagnostic criteria for disseminated intravascular coagulation (DIC) have been established by the Japanese Ministry of Health, Labor and Welfare, the International Society on Thrombosis and Hemostasis (ISTH) and the Japanese Association for Acute Medicine. The diagnostic criteria involving global coagulation tests, such as the Japanese Ministry of Health, Labor and Welfare criteria and the ISTH overt diagnostic criteria, are first-generation DIC diagnostic criteria, those involving global coagulation tests and changes in these tests such as the Japanese Association for Acute Medicine criteria, are second-generation DIC diagnostic criteria, and those including non-overt DIC diagnostic criteria involving global coagulation tests, changes in these tests and hemostatic molecular markers will be the future (third-generation) DIC diagnostic criteria. There are no significant differences in the three diagnostic criteria with respect to predicting poor outcomes. Therefore, the third generation of diagnostic criteria including hemostatic molecular markers is expected to be established. Standardization and the determination of adequate cutoff values should be required for each laboratory test.

The utility of a diagnostic scoring system for disseminated intravascular coagulation

Disseminated intravascular coagulation (DIC) is an acquired syndrome characterized by microvascular thrombosis resulting from systemic activation of coagulation, and it should be diagnosed and treated as early as possible. No single test is sufficiently accurate to establish or rule out a diagnosis of DIC. Therefore, diagnostic scoring uses a combination of several laboratory tests. Three diagnostic scoring systems are now available and validated. Because it is not easy to assess the superiority or inferiority of these scoring systems, it may be better to select the scoring system depending on the need for an early or affirmative diagnosis of DIC.

Modified non-overt DIC diagnostic criteria predict the early phase of overt-DIC

Diagnostic criteria for non-overt disseminated intravascular coagulation (DIC) have been proposed by the International Society of Thrombosis and Hemostasis, but are not useful for the diagnosis of early phase of overt-DIC (pre-DIC). Therefore, in the current study the non-overt DIC diagnostic criteria were modified using the global coagulation tests, the change rate in the global coagulation tests and molecular hemostatic markers to detect the pre-DIC state and were prospectively evaluated in 613 patients with underlying DIC disease. The frequencies of patients with DIC (DIC positive), late onset DIC, and without DIC (DIC absent) were 29.5%, 7.2%, and 63.3%, respectively. The modified non-overt-DIC criteria can correctly predict 43/44 patients (97.7%) who were DIC absent at admission and became DIC positive, within a week (late onset DIC state). The mortality rate was higher in DIC positive compared with pre-DIC (37.6% vs. 22.7%, P < 0.05) or DIC negative (37.6 vs. 13.7%, P < 0.01). It was also significantly higher in pre-DIC compared with DIC negative (P < 0.05). Thus, these modified non-overt DIC diagnostic criteria might therefore be useful for the diagnosis of early-phase DIC.

Disseminated intravascular coagulation, antithrombin III, and complement in meningococcal infections

Serial assessments of some blood coagulation factors, antithrombin III (AT III), and complement were made in 18 patients with meningococcal (mgc) infection. All patients displayed laboratory evidence of activation of the blood clotting system. Two patients showed clinical signs of disseminated intravascular coagulation. Only AT III differed significantly between patients with and without complications. There was no correlation between changes in blood clotting, activation of the complement system and the course or duration of the disease. These results do not enable one t identify patients who need specific prophylactic therapy. Controlled clinical trials, including administration of heparin, dextran, aprotinin, and others, are still required to ensure optimal treatment in fulminant mgc infections.

Hyperbaric oxygen therapy prevents coagulation disorders in an experimental model of multiple organ failure syndrome

OBJECTIVE

To evaluate the effects of hyperbaric oxygen (HBO) therapy on the coagulation cascade using an experimental model of multiple organ failure syndrome (MOFS).

DESIGN

MOFS was induced by zymosan (500mg/kg i.p.) in rats. HBO therapy (2ATA) was administered in a cylindrical steel chamber 4 and 11h after zymosan administration. In a separate set of experiments animals were monitored for 72h, and systemic toxicity was scored.

INTERVENTION

Eighteen hours after zymosan administration, rats were killed and blood samples were used for analysis of hemocoagulative parameters, hemodynamics, and arterial blood gas.

MAIN RESULTS

Zymosan administration caused MOFS by affecting the coagulation cascade, as shown by a significant increase in plasma levels of fibrinogen, tissue plasminogen activator, inhibitor of tissue plasminogen activator of type 1, and plasma levels of fibrin degradation products vs. control rats. Zymosan-induced MOFS was also characterized by a significant increase in von Willebrand antigen plasma levels vs. controls. Moreover, zymosan administration induced a significant fall in mean arterial blood pressure and alteration in blood gas values. HBO therapy significantly reduced the derangements of coagulation cascade, the fall in mean blood pressure and alteration in blood gas induced by zymosan administration.

CONCLUSIONS

The hypercoagulability induced by zymosan could be responsible for organ failure and death. Our data demonstrate that HBO therapy significantly prevents the alteration in the coagulation cascade and arterial blood gas in an experimental model of MOFS.

Are hemostasis and thrombosis two sides of the same coin?

Factor XII (FXII), a clotting enzyme that can initiate coagulation in vitro, has long been considered dispensable for normal blood clotting in vivo because hereditary deficiencies in FXII are not associated with spontaneous or excessive bleeding. However, new studies show that mice lacking FXII are protected against arterial thrombosis (obstructive clot formation) and stroke. Thus, FXII could be a unique drug target that could be blocked to prevent thrombosis without the side effect of increased bleeding.

Efficacy of low molecular weight heparin in a canine model of thromboplastin-induced acute disseminated intravascular coagulation

The aim of this study was to test the efficacy of different dosages of low molecular weight heparin (LMWH) in acute DIC which was induced in anaesthetised dogs by 4 h infusions of a canine lung thromboplastin extract. In all animals during the first 2 h, development of acute DIC was characterised by decreasing fibrinogen concentrations, platelet numbers, factor V- and antithrombin activities. Two hours after starting the thromboplastin infusion, intravenous LMWH treatment in different dosages started in groups 2 and 3 to achieve plasma levels between 0.27+/-0.01 and 0.36+/-0.02 anti-FXaUml(-1) or 0.62+/-0.08 and 0.90+/-0.07 antiFXaUml(-1) (mean+/-SD), respectively, during the time period of parallel administration of thromboplastin and LMWH (group 1=control; 4 dogs/group). In this time period, changes in factor V activity and fibrinogen concentration did not differ between group 2 and the control group. This was in contrast to group 3. The results of this study indicate that an efficacious interruption of the consumption reaction in cases of severe canine DIC requires high plasma heparin levels.

Disseminated intravascular coagulation

The diagnosis of disseminated intravascular coagulation (DIC) was initially based on the detection of microthrombi. Current diagnosis involves laboratory assessment of hemostatic abnormalities although additional studies may often be necessary. DIC is characterized by hypercoagulability and hyperfibrinolysis and is caused by high offense factors or low defense factors. DIC is divided two stages: overt-DIC and non-overt-DIC. The diagnosis of overt-DIC state is based on the criteria developed by the International Society of Thrombosis Haemostasis in conjunction with the Japanese Ministry Health and Welfare. However, no criteria are currently available for the diagnosis of non-overt DIC. Although scientifically supported modalities for treatment of DIC are few, the use of activated protein C (APC) and low-molecular-weight heparin appear to hold promise.

Coagulation/fibrinolysis abnormality and vascular endothelial damage in the pathogenesis of thrombocytopenic multiple organ failure

OBJECTIVE

Until recently, attention has been directed to disseminated intravascular coagulation as a cause of multiple organ failure (MOF). On the other hand, it has now become clear that humoral mediators play important roles in the pathogenesis of MOF. Therefore, we performed the present study in patients with thrombocytopenic MOF to investigate the relationship between various humoral mediators and vascular endothelial damage reported to be triggered by such humoral mediators in the pathogenesis of MOF.

DESIGN

A retrospective clinical study.

SETTING

Intensive care unit of a university hospital.

PATIENTS

The study included 18 thrombocytopenic patients whose conditions progressed to septic MOF (MOF group) and 20 others who did not progress to MOF (non-MOF group). The MOF group and non-MOF group were also presented with infection and with platelet counts of <100,000/mm3.

MEASUREMENTS AND MAIN RESULTS

The MOF group had fibrinolysis abnormality, as indicated by increased plasminogen activator inhibitor-1 level. On the other hand, the MOF group had increased polymorphonuclear elastase and polymorphonuclear-mediated fibrinogen degradation product levels with consequent prolonged elevation of thrombomodulin. In addition, both polymorphonuclear elastase and polymorphonuclear-fibrinogen degradation products were significantly positively correlated with thrombomodulin in the MOF group, but no such positive correlation was observed between interleukin-6 or plasminogen activator inhibitor-1 and thrombomodulin. In the non-MOF group, on the other hand, thrombomodulin exhibited no significant positive correlation with polymorphonuclear elastase, polymorphonuclear-fibrinogen degradation products, interleukin-6, or plasminogen activator inhibitor-1.

CONCLUSIONS

Our study provided evidence that vascular endothelial damage was the primary cause of organ failures in patients with thrombocytopenic MOF and that humoral mediators played a major role in the development of vascular endothelial damage in such patients. These results suggest that it is important to treat thrombocytopenic MOF as a condition of vascular endothelial damage, with weight placed on countermeasures against disorders of humoral mediators.

Fatal disseminated intravascular coagulation caused by Mycoplasma pneumoniae

We report fatal disseminated intravascular coagulation caused by Mycoplasma pneumoniae infection in a 7-year-old white boy. The diagnosis was based on relevant clinical material, absence of any other infections, a 4-fold rise in titer of complement fixation for M. pneumoniae and open lung biopsy findings. We discuss the association between M. pneumoniae and autoimmune mechanism.

Endoscopic hemoclipping for upper GI bleeding due to Mallory-Weiss syndrome

BACKGROUND

Endoscopic hemoclipping is known to be highly effective as hemostatic treatment for upper gastrointestinal bleeding. However, the efficacy and safety of hemoclipping for Mallory-Weiss syndrome (MWS) have not been reported. Thus, the aim of the present study was to assess prospectively the usefulness of endoscopic hemoclipping for MWS bleeding.

METHODS

This study was conducted from January 1994 to August 1999. Hemoclipping was performed when active bleeding (spurting, streaming or oozing), visible vessels or fresh adhesive clots were found on endoscopic examination. Patients who did not have any of these findings were conservatively treated. Follow-up endoscopy was performed within 24 hours, after 5 days and between 1 and 2 months after the procedure.

RESULTS

MWS was diagnosed in a total of 58 patients during the study. Hemoclipping was performed in 26 patients and was technically successful in all cases. The average number of hemoclips used was 2.8 +/- 1.6 (range 1 to 8). The number of hemoclips required for hemostasis depended on the nature of the bleeding. No complications, recurrent bleeding, or deaths resulted. Follow-up endoscopy showed no evidence of hemoclip-induced tissue injury and no impairment of Mallory-Weiss tears.

CONCLUSION

Endoscopic hemoclipping provided an effective and safe modality for obtaining hemostasis when bleeding is due to MWS.

Plasma levels of activated protein C-protein C inhibitor complex in patients with hypercoagulable states

Plasma levels of activated protein C (APC)-protein C inhibitor (PCI) were significantly increased in patients with disseminated intravascular coagulation (DIC), thrombotic thrombocytopenic purpura (TTP), acute myocardial infarction (AMI), pulmonary embolism (PE), or deep vein thrombosis (DVT) and in patients undergoing hemodialysis (HD). Plasma levels of APC-alpha(1)-antitrypsin (AT) complex were significantly increased in patients with DIC and in those with TTP. Plasma levels of PCI were significantly decreased in patients with DIC, non-DIC, or TTP and in those undergoing HD. In the pre-DIC stage, the plasma levels of APC-PCI complex were significantly increased but not those of APC-alpha(1)-AT complex. These data suggest that measurements of APC-PCI complex and APC-alpha(1)-AT complex may be useful for the diagnosis of DIC. After treatment of DIC, the plasma levels of APC-PCI complex and APC-alpha(1)-AT complex were significantly decreased, but not those of PCI. Plasma levels of thrombin-antithrombin complex (TAT), plasmin-alpha(2)-plasmin complex (PPIC), D-dimer, and soluble fibrin monomer (SFM) were markedly increased in patients with DIC or pre-DIC and were moderately increased in patients with non-DIC, TTP, AMI, PE, or DVT and in those undergoing HD. The receiving operating characteristic (ROC) analysis showed that SFM and the APC-PCT complex are useful markers for diagnosis of DIC. The specificity of plasma TAT and PPIC levels was low. The positive rate of APC-PCI complex was higher than 90% with DIC, TTP, AMI, PE, and it was higher than 60% with DVT and HD. Since the APC-PCI complex was elevated not only in patients with venous thrombosis but also in those with arterial thrombosis, components of the protein C pathway might be useful markers for the diagnosis of arterial thrombosis.

Elevated tissue factor levels in leukemic cell homogenate

Tissue factor (TF) antigen and activity were measured in leukemic cell homogenates. In leukemic cell homogenate, especially that of acute promyelocytic leukemia (APL), both TF antigen and activity were significantly higher than these levels in the mononuclear cells obtained from healthy volunteers. Both TF antigen and activity were significantly higher in myelocytic leukemia than in lymphocytic leukemia cells. In leukemic cell homogenates, there was a close correlation between TF antigen and TF activity. The TF activity/TF antigen ratio was significantly higher in myelocytic leukemia than in lymphocytic leukemia cells. As the TF activity was not increased in lymphocytic leukemia cell homogenates to which were added phospholipids, the decrease in TF activity in lymphocytic leukemia might not be due to phospholipid in the leukemic cell membrane. Values for TF activity, TF antigen, and the TF activity/TF antigen ratio in leukemic cell homogenate from patients with disseminated intravascular coagulation (DIC) were significantly higher than those in patients without DIC. Therefore, the measurement of TF antigen and activity in leukemic cells could be useful for the prediction of DIC.

Platelet activation and modulation of the induction of nitric oxide synthase in the conscious rat

Injection of lipopolysaccharide (LPS) (Salmonella W. Typhosa i.v. bolus) into conscious rats, induced a rapid drop of circulating platelets analogous to that induced by ADP. The animals showed a small fall in mean arterial blood pressure (MABP), an increase in heart rate and a significant increase in plasma nitrite and nitrate level. This result is consistent with the stimulation of an inducible NO synthase (i-NOS). The administration of the stable prostacyclin analogue, iloprost plus ADP or LPS, significantly protected against the decrease in free platelet number induced by ADP or LPS. The plasma nitrite and nitrate level stimulated by LPS was significantly reduced by iloprost and also by prostacyclin. These results are consistent with an inhibition of i-NOS by agents that increase the intracellular level of cAMP. The administration of the NO donor S-Nitroso-N-acyl-D-penicillamine (SNAP) plus ADP or LPS, significantly prevented thrombocytopenia induced by ADP and by LPS. SNAP did not decrease the plasma nitrite and nitrate level stimulated by LPS; furthermore it induced a significant increase of heart rate, without affecting MABP, suggesting a direct accelerating effect of NO on the sino-atrial node. The administration of S-nitroso-glutathione (GSNO), a stable nitrosothiol, plus ADP or LPS, significantly prevented thrombocytopenia induced by ADP but not by LPS. GSNO significantly reduced the plasma nitrite and nitrate level stimulated by LPS. These data demonstrate that the L-Arginine: NO pathway in vivo may be modulated by prostanoids and that compounds which increase cAMP, such as iloprost, are able to protect against LPS-induced early thrombocytopenia.

Association between pulmonary microthromboembolism and coagulation variables in hypercoagulable states: an autopsy study

OBJECTIVE

This autopsy study was carried out to investigate the relationship between the number of pulmonary microthromboemboli and coagulation tests in patients with coagulation abnormalities.

METHODOLOGY

Fifty-one patients in whom coagulation studies were performed within 2 days prior to death were studied. The coagulation tests included platelet counts, prothrombin times expressed as International Normalized Ratios (INR), activated partial thromboplastin times, fibrinogen concentrations, plasma fibrinogen/fibrin fragment E antigen levels, and plasma D-dimer levels. For microscopic analysis, five tissue blocks of the lung were taken from each subject and the number of pulmonary microthromboemboli per 20 cm2 of tissue sections was calculated.

RESULTS

Thirty-six of the 51 patients had pulmonary microthromboembolism. International Normalized Ratios were higher than 1.7 in 12 of 36 embolic and in two of 15 non-embolic patients (33.3% of sensitivity and 86.7% of specificity). There was no significant difference in D-dimer levels between the two groups. Multiple regression analysis identified that INR was significantly related to the number of microthromboemboli (P = 0.042).

CONCLUSIONS

D-dimer levels appear to be inappropriate as a single screening test for disseminated intravascular coagulation (DIC) in critically ill patients because the levels in these subjects are elevated irrespective of the presence of microthromboemboli. Because of the high specificity, INR could be a specific marker for microthromboemboli. The significant association between the number of microthromboemboli and INR might indicate the importance of the extrinsic pathway in the initiation of DIC.

Relationship between platelet activation and cytokines in systemic inflammatory response syndrome patients with hematological malignancies

We investigated the significance of platelet activation and platelet-derived microparticles (PMP) in 14 patients with systemic inflammatory response syndrome (SIRS) and hematological malignancies. In the phenotypic analysis of lymphocytes, there was a significant decrease of total and activated T cells after panipenem/betamipron (PAPM/BP) treatment (p<0.05). The percentages of helper/inducer T cells and suppressor/cytotoxic T cells were insignificantly decreased after PAPM/BP treatment. The number of natural killer (NK) cells of potent activity was significantly decreased after treatment (p<0.05). The levels of the cytokines interleukin (IL)-1beta, IL-6, and IL-8 in the patients were increased before treatment. IL-1beta concentrations were not changed after treatment. In contrast, the IL-6 and IL-8 levels were significantly decreased (p<0.05) after treatment, while tumor necrosis factor (TNF)-alpha and interferon gamma remained almost normal. We found an increase of soluble IL-2 receptor (sIL-2R) and soluble vascular cell adhesion molecule-1 (sVCAM-1) levels in the patients before treatment. After treatment, the sIL-2R concentrations tended to be decreased and sVCAM-1 levels showed a significant decrease (p<0.01). In contrast, soluble thrombomodulin (sTM) level did not change. Regarding the platelet activation markers, CD62P, CD63, and PMP levels in the patients were increased before treatment. CD62P and CD63 tended to be decreased after treatment, whereas PMP levels were significantly reduced from 1,056+/-103 to 762+/-64/10(4) platelets (p<0.05). Furthermore, CD62P, CD63, and PMP correlated with the levels of IL-6 and IL-8. These results suggest that activated platelets and PMP may be predictive markers in pre-disseminated intravascular coagulation and hypercytokine conditions related to SIRS.

Prediction of neonatal sepsis by thromboelastography

The thromboelastogram (TEG) measures functional defects in coagulation, from fibrin formation through platelet aggregation to fibrinolysis. It is comparable with standard laboratory tests of coagulation; however, it provides additional useful qualitative information. This prospective study documents the TEG findings in 103 neonates: 60 were normal and healthy and provided a reference range; 12 surgical babies had established sepsis, 15 had early sepsis, and 16 were non-septic. TEG abnormalities were detected only in those patients with early and established sepsis. Abnormalities were found in all but 1 of this group of 27 patients (96%), whereas only 16 (59%) had thrombocytopenia, 2 (6%) had leukocytosis, and 6 had leukopenia. The TEG had a sensitivity for sepsis of 96% and a specificity of 96%. This exceeds the values for routine full blood-count parameters and other laboratory indicators of sepsis. It was found to be a simple, quick, and sensitive indicator of early sepsis that enabled the clinicians to manage septic newborns earlier.

Increased plasma-soluble fibrin monomer levels in patients with disseminated intravascular coagulation

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.

Modulation of the endothelial procoagulant response to lipopolysaccharide and tumour necrosis factor-alpha in-vitro: the effects of dexamethasone, pentoxifylline, iloprost and a polyclonal anti-human IL-1 alpha antibody

Endothelial expression of tissue factor (TF), a potent procoagulant molecule, is increased in response to inflammatory mediators such as lipopolysaccharide (LPS), tumour necrosis factor (TNF) and interleukin-1 (IL-1). We have examined the effects of three antiinflammatory agents and a polyclonal anti-human IL-1 alpha antibody on the human endothelial TF response to E. coli 0111:B4 LPS and recombinant TNF alpha (rTNF alpha) in vitro. In contrast to the expected inhibitory effect, dexamethasone, pentoxyfilline and iloprost failed to block TF expression when administered simultaneously or 30 minutes prior to stimulation with either LPS or rTNF alpha. Inhibition of procoagulant activity was demonstrated with the anti-IL-1 alpha antibody, suggesting that endothelial derived IL-1 alpha is partially responsible for the TF response to the agonists employed. The failure of the antiinflammatory agents to inhibit endothelial TF expression highlights the possibility that therapeutic agents that modulate the circulating monocyte response to LPS and TNF alpha may not ameliorate the endothelial dysfunction that is also induced by these inflammatory mediators.

Disseminated intravascular coagulation after liver resection: retrospective study in patients with biliary tract carcinoma

BACKGROUND

Disseminated intravascular coagulation (DIC) after hepatectomy is not well understood. The objective of this retrospective study was to evaluate hemostatic changes after extensive liver resection and to elucidate the frequency of posthepatectomy DIC.

METHODS

In 100 patients without cirrhosis who underwent resection of two or more segments of the liver for biliary tract carcinoma, various hemostatic parameters were measured before and after resection, and the liver function of each patient was assessed.

RESULTS

In patients with posthepatectomy liver failure, platelet count, fibrinogen concentrations, and prothrombin time were significantly lower than in those without such failure. Serum levels of fibrin degradation product did not differ significantly between the two groups. The minimum platelet count was significantly negatively correlated with serum total bilirubin level. Posthepatectomy DIC occurred in 2.0% of the patients.

CONCLUSIONS

After extensive liver resection patients exhibited a decreased platelet count with hepatic dysfunction. However, this condition rarely resulted in DIC, at least in patients without cirrhosis and serious postoperative complications.

Incidence of pulmonary thromboembolism, infarction and haemorrhage in disseminated intravascular coagulation: a necroscopic analysis

BACKGROUND

The pathological features of the lung in disseminated intravascular coagulation (DIC) have not been established. This study was carried out on lungs taken at necropsy to examine the incidence and extent of thromboembolism, infarction, and haemorrhage.

METHODS

The subjects were 87 patients whose illnesses were complicated by DIC and 64 patients who showed no abnormalities of blood coagulation in their terminal illness. The lungs were fixed by intrabronchial infusion of 10% formalin, cut into 5 mm thick slices, and each cut surface was carefully examined for macroscopic thromboembolism, infarction, and haemorrhage. Five tissue blocks per case were taken for quantitative analysis of microscopic thromboembolism.

RESULTS

In the control group macroscopic thromboembolism was identified in 20 cases (31.3%), infarction in one, and haemorrhage also in one. Moreover, fibrin thrombosis was seen in 13 cases (20.3%) and microthromboembolism in 24 (37.5%). Of the 87 patients with DIC, thromboembolism was found in 51 cases (58.6%), infarction in six, haemorrhage in 14, microscopic fibrin thrombosis in 43 (49.4%), and microthromboembolism in 45 (51.7%). Macroscopic thromboembolism, haemorrhage, and fibrin thrombosis were found more often in the patients with DIC.

CONCLUSIONS

In addition to fibrin thrombosis, macroscopic thromboembolism and haemorrhage were the main pathological findings in the lungs of patients dying with DIC. The frequency of pulmonary infarction increased in proportion to the frequency of thromboembolism.

Combined treatment with antibiotic, heparin and streptokinase--a new approach to the therapy of bacterial osteomyelitis

Combined treatment by continuous intravenous infusion of a selected antibiotic and heparin and/or streptokinase was elaborated as a method of causal, systemic treatment of bacterial osteomyelitis. The aim of the combined treatment was to overcome infection and disturbances in the coagulation and fibrinolysis system which lead to impairment of the bone blood supply and its subsequent necrosis as the main factor in the aetiopathology of osteomyelitis. Between 1969 and 1991, combined treatment was introduced in 63 patients with acute onset disease or with chronic osteomyelitis. Osteomyelitis was located in the mandible in 38 patients and in the long bones in 14 patients. Prior to combined treatment, moderate bone surgery was performed in 21 patients, while 31 patients were excluded from surgery. Combined treatment with an antibiotic and heparin (A+H) was performed in 43 patients, and the other 6 patients had infusion of an antibiotic, streptokinase and heparin (A+S+H). The authors' method of combined treatment offers a new approach and an alternative to routinely-ordered antibiotic therapy and radical surgery, which allow frequent recurrences of the disease, a long-lasting course and severe complications.

Elevated plasma tissue factor antigen level in patients with disseminated intravascular coagulation

The plasma tissue factor (TF) antigen level was measured in patients with disseminated intravascular coagulation (DIC). The plasma TF antigen was detected in normal volunteers, and it was significantly higher in DIC patients than in non-DIC patients. However, in some patients with DIC, the plasma TF antigen level was within the normal range. The plasma TF antigen level in patients with DIC significantly decreased after therapy, but it was not correlated with organ failure or outcome. The plasma TF antigen level in patients with DIC was not correlated with other hemostatic markers. The plasma TF antigen level tended to be higher in DIC patients with nonlymphoid leukemia than in those with lymphoid tumor. TF might be implicated in the occurrence and progression of DIC.

Prognostic role of screening tests of haemostasis and underlying diseases in acute disseminated intra-vascular coagulation in adults

The significance of precipitating causes of acute disseminated intra-vascular coagulation (DIC) and the severity of derangement of haemostasis based on laboratory investigations carried out initially were evaluated in 98 patients and was related to the fatal outcome in them. It was seen that septicaemia was the commonest precipitating cause. Survival was better in patients in whom DIC was precipitated by obstetric causes compared with those with septicaemia (P < 0.01). Death was also more frequently associated in patients with higher prothrombin time (PPT) ratio (> 1.5) and/or higher activated partial thromboplastin time (APTT) ratio (> 2.5) as compared to their lower values (P < 0.01 each). Death occurred in all the seventeen patients in whom septicaemia was present along with PPT ratio of > 1.5. It is concluded that deranged haemostasis and presence of septicaemia both independent of each other, contribute to the fatal outcome in acute DIC. Combination of both is associated with poorest prognosis.

The generation of thrombin in vivo induces the selective loss of high molecular weight multimers of von Willebrand factor and the reversible sequestration of platelets

Various levels of thrombin generation were induced by the infusion of a combination of factor Xa (F.Xa) and phosphatidylcholine/phosphatidylserine (PCPS) vesicles into normal dogs and non-human primates. In the dog, an immediate loss of von Willebrand factor antigen (vWF:Ag) with a progressive recovery to normal levels by 45 min was observed. Multimeric assay demonstrated a selective loss of high molecular weight multimers (HMWM) with subsequent replacement. At low doses, in non-human primates (chimpanzees), identical changes to those seen in the dog were observed and this was associated with an equivalent loss of ristocetin co-factor activity (vWF:RCoF). At high dose a reversal of the wWF response occurred with levels increasing to twice that of baseline values by 2 min and multimeric analysis demonstrated the presence of abnormally large multimers and increased vWF:RCoF specific activity, suggesting that the response at each dosage reflected a net balance of consumption over release. This was supported by in vitro simulation where increasing thrombin generation was associated with a selective loss of HMWM without replacement. In both species, an immediate fall in platelet count occurred and this was directly correlated with the amount of thrombin generated. Full recovery occurred within 45 min and isotopic labelling studies demonstrated that platelet sequestration rather than consumption was occurring. These studies demonstrate that thrombin generation in vivo is associated with a selective loss of the multimeric forms of vWF known to interact with platelets and this may provide an in vivo model to characterize the physiology/pathophysiology of this primary event in haemostasis.

Increased vascular endothelial cell markers in patients with disseminated intravascular coagulation

We examined vascular endothelial cell markers, thrombomodulin (TM), plasminogen activator inhibitor-I (PAI-I), tissue plasminogen activator (t-PA), and von Willebrand factor, in 80 patients with disseminated intravascular coagulation (DIC). The levels of thrombin-antithrombin III complex (TAT), plasmin-alpha 2 plasmin inhibitor complex (PIC) and FDP-D-dimer were significantly increased both before and after the onset of DIC, but were not correlated with organ failure or prognosis. However, the PIC/TAT ratio was lower in patients with poor prognosis than in those with good prognosis, and it was also lower in those with organ failure than in those without. Plasma TM, PAI-I, and t-PA levels were increased in DIC patients with organ failure or poor outcome, but were not significantly increased before the onset of DIC. We consider that the prognosis of patients with DIC might be related to organ failure or endothelial cell damage and that plasma levels of TM, PAI-I, and t-PA might be useful in the detection of these disorders and in assessing prognosis. A hypofibrinolytic state might enhance organ failure in patients with DIC.