Hemostatic abnormalities in patients with pulmonary embolism compared with that in deep vein thrombosis

Plasma levels of haemostatic factors in patients with pulmonary embolism on admission and seven months later

INTRODUCTION

With the exception of D-dimer, not much is known about the plasma levels of haemostatic factors during acute venous thromboembolism (VTE) compared to their basic levels in a stable phase. The goal of this study was to examine how plasma levels of factor V, VIII, XIIIa, von Willebrand factor antigen (vWF:Ag), fibrinogen, thrombomodulin evolve from the point of diagnosis of acute VTE to the end of standard treatment period.

METHODS

Sixty-three consecutive patients (mean 57, range 18-86 years, 33 females) with acute pulmonary embolism (PE) were included. Laboratory samples were collected upon arrival (acute phase) and seven months later (stable phase). Fifteen similar aged individuals served as controls.

RESULTS

Plasma levels of factor XIIIa (87.5% vs 117.7%, P < .001) and soluble thrombomodulin (36.6 vs 47.5 ng/L, P < .001) were lower, whereas plasma levels of vWF:Ag (2.66 vs 2.01 IU/mL, P < .001) and fibrinogen (4.3 vs 3.9 g/L, P < .05) were higher on admission compared to the stable phase. In the stable phase, vWF:Ag (2.01 vs 1.43 IU/mL, P < .01) and soluble thrombomodulin (47.5 vs 38.0 ng/mL, P < .05), but not FXIIIa levels, were higher in PE patients compared to healthy controls.

CONCLUSION

This study confirms the concept of FXIIIa consumption during acute phase of VTE by showing its intraindividual normalization during the follow-up. vWF:Ag, known to be associated with the risk of VTE, was constantly elevated in the majority of the patients. Soluble thrombomodulin levels were lower in acute phase compared to stable phase, a finding which significance needs to be evaluated in the future.

Decreased plasma levels of activated factor VII in patients with deep vein thrombosis

BACKGROUND

The initiating trigger in the development of deep vein thrombosis (DVT) remains unidentified. It has been suggested that tissue factor (TF)-bearing microparticles play a key role, which indicates a role for the TF pathway in the initiation of DVT.

OBJECTIVE

To assess the role of the TF pathway in the initiation of venous thrombosis, we measured plasma levels of factor VII and VIIa in patients with acute DVT and in controls.

METHODS

We included 148 patients diagnosed with acute DVT and 179 controls in this study. Antigen levels of FVII and FVIIa were measured by using assays recently developed in our laboratory.

RESULTS

Median FVII levels in patients were 109.8% (interquartile range [IQR] 86.0-153.2) compared with 102.2% (IQR 76.1-141.7) in controls. Individuals with FVII levels in the upper quartile had a 1.6-fold increased risk for the presence of a DVT (odds ratio 1.6, 95% confidence interval 0.8-3.1). Median FVIIa levels in patients were 50.2 ng mL(-1) (IQR 25.2-86.1) compared with 96.6 ng mL(-1) (69.9-168.9) in controls. Individuals with FVIIa levels in the lowest quartile had a > 5-fold increased risk for the presence of a DVT (odds ratio 5.5, 95% confidence interval 2.8-10.6). Both risks did not change substantially after adjustment for potential confounders.

CONCLUSION

Decreased plasma levels of FVIIa in patients with deep vein thrombosis may indicate ongoing consumption of FVIIa and suggest a contributory role for TF in venous thrombus formation.

Risk factors for deep vein thrombosis after orthopedic surgery and the diagnostic value of D-dimer

BACKGROUND

This study was prospectively designed to determine the risk factors of deep vein thrombosis (DVT) in patients who underwent different surgeries, and to evaluate the efficacy and accuracy of plasma D-dimer level as a screening test.

METHODS

From June 2013 to June 2014, 360 consecutive patients undergoing orthopedic surgery were evaluated. All patients underwent ultrasonography preoperatively and on postoperative day 7. Plasma D-dimer levels were estimated by latex immunoturbidimetry on the day of surgery and on postoperative days 1, 3, and 7.

RESULTS

Of the 360 patients in this study, 339 patients completed the analysis. Among them, DVT was confirmed in 28 (8.26%) patients based on ultrasonographic findings. Multivariate logistic analysis revealed that body mass index was an independent risk factor for developing DVT (P = 0.018) and D-dimer levels on postoperative days 1 and 7 were independently correlated with the development of DVT (P = 0.019 and P < 0.001, respectively). The receiver operating characteristic curve analysis determined that the area under the curve was largest (0.752) when using D-dimer level on postoperative day 7 as diagnostic index, and the sensitivity and specificity were 71.4% and 81.7% at the cut-off value of 6.17 μg/mL, respectively. The elevated D-dimer levels followed the same tendency toward a double-peaked distribution with peaks at days 1 and 7 postoperatively.

CONCLUSION

D-dimer level was a useful screening test to exclude DVT, and the cut-off values of D-dimer determined in this study will provide a reference for the absence of DVT to a certain extent.

Elevated fibrin-related markers in patients with malignant diseases frequently associated with disseminated intravascular coagulation and venous thromboembolism

OBJECTIVE

Many patients with malignant diseases are frequently complicated with some type of thrombosis, such as venous thromboembolism (VTE) or disseminated intravascular coagulation (DIC).

METHODS

This retrospective study was designed to examine the frequency of thrombosis in 478 patients with malignant diseases in comparison to that observed in 121 patients without malignant diseases and to evaluate the efficacy of fibrin-related markers (FRMs), such as soluble fibrin, fibrinogen and fibrin degradation products and D-dimer, in diagnosing thrombosis.

RESULTS

The frequency of thrombosis, including 62 cases of VTE, 63 cases of DIC and nine cases of cerebrovascular thrombosis, was significantly higher in the patients with malignant diseases (28.0%) than in the patients without malignant diseases (12.5%). DIC was frequently detected in the patients with hepatic cell cancer and hematopoietic malignancy, while VTE was frequently observed in the patients with colon cancer, breast cancer and urinary tract cancer. The FRMs levels were significantly higher in the patients with thrombosis than in the patients without thrombosis. A receiver operating characteristic analysis showed these markers to be useful for diagnosing thrombosis.

CONCLUSION

Patients with malignant diseases have a high risk of thrombosis, and elevated FRMs levels are useful for diagnosing thrombosis in patients with malignant diseases.

Time course of soluble P-selectin and von Willebrand factor levels in trauma patients: a prospective observational study

Background

Coagulopathy often develops in patients with serious trauma and is correlated with the clinical outcome. The contribution of platelet activity and endothelial dysfunction to trauma-induced coagulopathy remain to be defined. The purpose of this study was to investigate the time courses of soluble P-selectin (sPsel, an index of platelet activation) and von Willebrand factor (VWF, an index of endothelial dysfunction) in trauma patients and elucidate their relationship to coagulation parameter levels, the presence of coagulopathy, and patient outcome.

Methods

This prospective observational study, which took place in a university hospital intensive care unit (ICU), included 82 severely injured trauma patients. The sPsel, VWF antigen, protein C, and factor VII levels were measured and routine coagulation tests were performed upon admission to ICU and daily within the first week. The 30-day mortality rate was also determined.

Results

Thirty-seven (45.1%) patients developed coagulopathy upon admission to the ICU, and the 30-day mortality rate was 20.7% (n = 17). Both the admission sPsel and VWF levels were lower in patients with coagulopathy than in those without (p < 0.05) and were significantly correlated with the protein C and factor VII levels, respectively (all p < 0.05). The VWF levels were lower during the first 3 days and higher on day 7 after admission in nonsurvivors than in survivors (all p < 0.05). No significant differences in sPsel levels were found between nonsurvivors and survivors on each day during the first week.

Conclusion

In severely injured trauma patients in the ICU, lower levels of sPsel and VWF on admission were associated with the presence of coagulopathy and might not predict a better outcome. An increase in the VWF level at the end of the first week after admission to ICU was associated with increased 30-day mortality.

Recurring extracorporeal circuit clotting during continuous renal replacement therapy resolved after single-session therapeutic plasma exchange

We report a case of a 17-year-old white male with multiple fractures and multiorgan failure who developed oliguric acute renal failure requiring continuous renal replacement therapy. Repeated clotting of the extracorporeal circuit (ECC) prevented delivery of a minimally acceptable dose of renal replacement therapy despite adequate anticoagulation and dialysis catheter exchanges. Evaluation for a primary hypercoagulable state was negative, but his fibrinogen was elevated (1,320 mg/dL, normal range: 150-400 mg/dL), which is likely induced by his severe inflammatory state. A single session of therapeutic plasma exchange (TPE) with albumin and normal saline replacement was performed with subsequent drop in fibrinogen to 615 mg/dL. No further episodes of premature ECC clotting occurred, suggesting plasma factor(s) removed may have contributed to the clinical hypercoagulable state. TPE may play an adjunctive role in select cases of recurrent ECC clotting refractory to current anticoagulation techniques.

Elevated fibrin-related markers in patients with malignant diseases suspected of having thrombotic disorders

BACKGROUND

Most patients with malignant diseases are frequently complicated with some type of thrombosis, such as disseminated intravascular coagulation (DIC) or deep vein thrombosis (DVT)/pulmonary embolism (PE).

OBJECTIVE

The cohort and retrospective study was designed to examine the frequency of thrombosis in patients with malignant diseases and to evaluate the efficacy of D-dimer and soluble fibrin (SF) for the diagnosis of thrombosis.

PATIENTS/METHODS

The plasma concentrations of D-dimer and SF were measured in patients with malignant diseases suspected of having thrombosis. D-dimer and SF were measured using a latex aggregation assay.

RESULTS

Thrombosis was observed in 23.3% of the patients with malignant diseases. Disseminated intravascular coagulation was frequently observed in patients with hepatoma, and DVT/PE was frequently observed in patients with colon cancer, lung cancer, and uterine cancer. The plasma levels of D-dimer and SF were increased in malignant diseases, especially hepatoma. Plasma levels of D-dimer and SF were significantly higher in patients with thrombosis in comparison to patients without thrombosis. A receiver operating characteristic (ROC) analysis showed the D-dimer and SF levels to be useful in the diagnosis of thrombosis.

CONCLUSION

Elevated D-dimer and SF levels might indicate a high risk of thrombosis in patients with malignant disease; however, these assays still need to be standardized.

The multi-functional serpin, protein C inhibitor: beyond thrombosis and hemostasis

Protein C inhibitor (PCI) is a member of the serine protease inhibitor (serpin) family. PCI was initially found to be an inhibitor of activated protein C, and later shown to be a potent inhibitor of blood coagulation and fibrinolysis such as that mediated by urokinase type-plasminogen activator. Therefore, the protein came to be known as plasminogen activator inhibitor-3. It also inhibits proteases involved in fertilization. PCI is broadly conserved, and is found in human, rhesus monkey, cow, rabbit, rat, mouse and chicken. The human PCI gene is located on chromosome 14q32.1 in a cluster of genes encoding related serpins. Sp1- and AP2-binding sites in the 5'-flanking region act as promoter and enhancer, respectively, for its expression in the liver. PCI mRNA is expressed in many organs in primates, but only in the reproductive organs in rodents. Recent studies using transgenic mice expressing the human gene have suggested that PCI is also involved in regulation of lung remodeling, tissue regeneration, vascular permeability, proteolysis in the kidney and tumor cell invasion. A protease inhibitor-independent activity of PCI, the prevention of anti-angiogenesis and metastasis of tumor cells, has also been observed. Thus, PCI is a unique multi-functional serpin playing diverse roles in the thrombosis and hemostasis in multiple organs and tissues of a variety of species.

Decreased plasma soluble thrombomodulin levels as a risk factor for pulmonary thromboembolism

OBJECTIVE

To observe the changes of the plasma soluble thrombomodulin (sTM) concentrations in patients with pulmonary thromboembolism (PTE) and assess the association between plasma sTM concentration and the risk of PTE.

PATIENTS AND METHODS

We measured plasma concentrations of sTM, protein C (PC) and protein S (PS) and examined the association between those plasma markers and the risk of PTE in 72 selected PTE patients and 70 controls.

RESULTS

Significant difference was identified in plasma sTM level between overall PTE patients and controls. Female PTE patients had statistically lower sTM concentrations than male patients. A positive linear correlation was found between plasma sTM concentration and age in female patients. Decreased plasma sTM concentration was associated with a continuously and progressively increased risk for PTE in women. The concentrations of plasma PC and PS did not differ between groups and no significant quantitative association was identified between the risk of PTE and the levels of plasma PC or PS.

CONCLUSION

Decreased plasma sTM concentration is associated with an increased risk of PTE in women.

Elevated levels of prothrombin fragment 1 + 2 indicate high risk of thrombosis

Prothrombin fragment 1 + 2 (F1 + 2) is considered to be useful for diagnosis of thrombosis. However, the evidence for a diagnosis of thrombosis by F1 + 2 is still not well established. The plasma concentrations of F1 + 2, soluble fibrin, D-dimer, and thrombin-antithrombin complex were measured in 694 patients suspected of having thrombosis and then were correlated with thrombosis. Plasma concentrations of F1 + 2, soluble fibrin, D-dimer, and thrombin-antithrombin complex were significantly higher in patients with thrombosis, compared with patients without thrombosis. When cutoff values of more than 300 pmol/L for F1 + 2 were used for the diagnosis, more than 50% of the patients were thus found to have thrombosis. The findings showed that F1 + 2, soluble fibrin, D-dimer, and thrombin-antithrombin complex have similar diagnostic ability. The plasma concentration of F1 + 2 closely was well correlated with thrombin-antithrombin complex, soluble fibrin, and D-dimer. Finally, F1 + 2 is one of the most useful parameters for the diagnosis of thrombosis.

Haplotype of thrombomodulin gene associated with plasma thrombomodulin level and deep vein thrombosis in the Japanese population

INTRODUCTION

Thrombomodulin (TM) is an essential cofactor in protein C activation by thrombin. Here, we evaluated the contribution of genetic variations in the TM gene to soluble TM (sTM) level and deep vein thrombosis (DVT) in Japanese.

PATIENTS AND METHODS

We sequenced the TM putative promoter, exon, and 3'-untranslated region in DVT patients (n=118). Among 17 genetic variations we identified, two missense mutations (R385K, D468Y) and three common single nucleotide polymorphisms (-202G>A, 2487A>T, 2729A>C) were genotyped in a general population of 2247 subjects (1032 men and 1215 women) whose sTM levels were measured. We then compared the frequency of these mutations in DVT patients with that in the age, body mass index-adjusted population-based controls.

RESULTS

We identified one neutral mutation (H381) and three missense mutations (R385K; n=2, A455V; n=53 heterozygous, n=14 homozygous, D468Y; n=2) of TM in the DVT patients. Age-adjusted mean values of sTM were lower in C-allele carriers of 2729A>C than in noncarriers in the Japanese general population (women: 16.7+/-0.3 U/ml vs. 17.9+/-0.2 U/ml, p<0.01, men: 19.4+/-0.3 U/ml vs. 20.4+/-0.3 U/ml, p=0.03). Additionally, the CC genotype of this mutation was more common in the male DVT patients than in the male individuals of the general population (odds ratio=2.76, 95% confidence interval=1.14-6.67; p=0.02). This mutation was in linkage disequilibrium (r-square>0.9) with A455V mutation.

CONCLUSIONS

TM mutations, especially those with a haplotype consisting of 2729A>C and A455V missense mutation, affect sTM levels, and may be associated with DVT in Japanese.

Elevated levels of soluble fibrin or D-dimer indicate high risk of thrombosis

BACKGROUND

Fibrin-related markers such as soluble fibrin (SF) and D-dimer are considered useful for the diagnosis of thrombosis. However, the evidence for diagnosis of thrombosis by fibrin-related markers is not well-established.

OBJECTIVE

To evaluate the cutoff values of D-dimer and SF in the diagnosis of thrombosis.

PATIENTS AND METHODS

Plasma concentrations of SF and D-dimer were measured in 784 inpatients suspected of having thrombosis between 1 August 2003 and 31 December 2004, and then correlated with thrombosis.

RESULTS AND CONCLUSIONS

Plasma concentrations of D-dimer and SF were significantly higher in patients with disseminated intravascular coagulation (DIC), deep vein thrombosis (DVT) and cerebral thrombosis, compared with those in patients without thrombosis. When cutoff values of > 3.0 microg mL(-1) for D-dimer and > 6.0 microg mL(-1) for SF were used for the diagnosis, more than 50% of patients (with the exception of liver transplant patients and postoperative patients) had thrombosis. Receiver operating characteristic analysis showed that SF was more useful than D-dimer for the diagnosis of thrombosis (i.e. DVT and DIC). The cutoff value of D-dimer (7.87 microg mL(-1)) was the same for DVT and DIC, while that of SF was slightly lower for DVT (7.05 microg mL(-1)) than for DIC (8.60 microg mL(-1)). Our findings suggest that high levels of plasma fibrin-related markers reflect high risk for thrombosis.

Monocytes and plasma tissue factor levels in normal individuals and patients with deep venous thrombosis of the lower limbs: potential diagnostic tools?

INTRODUCTION

Tissue factor (TF) is the main physiological initiator of blood coagulation; it is membrane-bound on monocytes (mTF) and free in plasma (pTF). Abnormal expression of TF by monocytes has been implicated in various diseases. We therefore quantified monocytes expressing TF and pTF levels in patients with lower-limb deep venous thrombosis (DVT).

MATERIALS AND METHODS

DVT was confirmed by Duplex Scan. Blood mTF levels under resting condition (baseline), after incubation without (unstimulated) and with (stimulated) lipopolysaccharide (LPS), and total mTF levels were determined by flow cytometry using two analytical methods (Histogram and Quadrant-Statistics). Plasma TF levels were measured using an enzyme-linked immunoabsorbent assay (ELISA). Results were compared with age-matched controls.

RESULTS

Histogram analysis in patients with DVT showed significantly elevated mTF levels for baseline, unstimulated and total mTF over controls. For Quadrant-Statistics, DVT patients also showed significantly raised baseline, unstimulated, stimulated and total mTF. Similarly, pTF levels were significantly raised in subjects with DVT compared to controls. Baseline mTF levels correlated with pTF levels by Histogram and Quadrant-Statistics analysis. Using the relative operating characteristic (ROC) curve, baseline mTF and pTF assays displayed sensitivity and specificity in detecting DVT. Quadrant-Statistics baseline mTF and pTF gave the best discrimination.

CONCLUSIONS

The TF assays used in this study showed acceptable sensitivity and specificity and are cost-effective and practical. Therefore, they should be considered in patients with, or at risk of, DVT.

Diagnosis of deep vein thrombosis by plasma-soluble fibrin or D-dimer

The present study was designed to determine the cutoff values of D-dimer and soluble fibrin (SF) for the diagnosis of deep venous thrombosis (DVT) and pulmonary embolism (PE) in Japanese patients. Plasma levels of these molecules were measured in 243 patients suspected of having DVT and 100 healthy volunteers (controls). Out of 243 patients, 20 patients were diagnosed with DVT. In the control group, plasma levels of D-dimer and SF did not show normal distribution, and the 95% confidence intervals (CI) of D-dimer and SF were 2.45 microg/mL and 6.92 microg/mL, respectively. Plasma levels of D-dimer and SF of patients with DVT were significantly higher than of those without DVT. In patients with DVT, the minimum values of D-dimer and SF were 1.71 and 1.44 microg/mL, respectively. When the cutoff value was set at the average+1 SD of those of the control (D-dimer, about 1.8 microg/mL; SF, about 1.4 microg/mL), 1 and 0 patient with DVT was overlooked, respectively. The sensitivity and specificity of D-dimer and SF for DVT were 95% and 100%, and 61.9% and 53.8%, respectively. When the cutoff value was set at 95% CI of the control (D-dimer, 2.5 microg/mL; SF, 6.9 microg/mL), 2 and 9 patients with DVT were overlooked, respectively. The sensitivity and specificity of D-dimer and SF were 90% and 50%, and 77.6% and 88.3%, respectively. When the cutoff values set at 2.5 microg/mL of D-dimer or 6.9 microg/mL of SF, 1 DVT patient was overlooked, with sensitivity and specificity of 95% and 69.5%. Our data suggest that both D-dimer and SF are useful markers for the diagnosis of DVT and that measurement of both D-dimer and SF increases the sensitivity and specificity for the diagnosis of DVT/PE.

Elevated plasma levels of fibrin degradation products by granulocyte-derived elastase in patients with deep vein thrombosis

Plasma levels of granulocyte-derived elastase (GE-XDP), D-dimer and soluble fibrin (SF) were examined in 53 patients with deep vein thrombosis (DVT) and in 100 healthy volunteers. The mean plasma level of D-dimer was 0.92+/-0.81 microg/ml (+/-S.D.) in healthy volunteers and the mean+2 S.D. value (cutoff value for DVT) was 2.53 microg/ml, which was higher than that used in Europe and North America. Plasma levels of GE-XDP, D-dimer and SF were significantly higher in patients with DVT than in healthy volunteers, and diminished after 1 week of treatment with heparin, urokinase or tissue type plasminogen activator, though were still higher than those of the control subjects. The sensitivity of GE-XDP, D-dimer and SF for DVT was 81.1%, 75.5% and 79.2%, respectively. GE-XDP levels correlated with those of D-dimer and SF. Our results indicate that GE-XDP is a potentially useful marker for the diagnosis of DVT, suggesting that granulocytes are activated in patients with DVT. In our system, the cutoff value of D-dimer for the diagnosis of DVT is higher than in western countries, probably due to the use of different analytical assays.

High prevalence of anti-prothrombin antibody in patients with deep vein thrombosis

The present study was designed to determine the prevalence of lupus anticoagulant (LA) antibody and several antibodies for antiphospholipid syndrome (APS) in patients with deep vein thrombosis (DVT)/pulmonary embolism (PE) (n = 48), cerebral thrombosis (CT, n = 30), systemic lupus erythematosus (SLE, n = 22), and idiopathic thrombocytopenic purpura (ITP, n = 30). The presence of antibodies was examined by using the respective ELISA kits. LA was positive in 38.6% of patients with DVT/PE, suggesting that LA is one of the most important risk factors in DVT/PE. The highest prevalence of anti-beta(2) glycoprotein I (beta(2)GPI) IgG was in CT and SLE, followed by DVT, and none in ITP and healthy volunteers (control, n = 40), suggesting that it is related to thrombosis, particularly arterial thrombosis. The highest prevalence of anti-prothrombin (aPT) IgG antibody was in DVT, followed by CT and SLE, and none in ITP and the control, suggesting that it is related to thrombosis, especially venous thrombosis. The highest prevalence of antiphospholipid (aPL) IgG was in DVT, CT, and SLE, but 0% in ITP and control. On the other hand, aPL IgM, anti-annexin V IgG, and anti-annexin V IgM were positive in patients both with and without thrombosis, suggesting that they are not related to thrombosis. Our results indicated that among the anti-phospholipid antibodies, LA is the most sensitive marker for APS while anti-beta(2)GPI IgG, aPT IgG, and aPL IgG are risk factors for thrombosis. In particular, aPT IgG is a significant marker for DVT/PE.

Polymorphisms in coagulation factor genes and their impact on arterial and venous thrombosis

Arterial and venous thromboses, with their clinical manifestations such as stroke, myocardial infarction (MI), or pulmonary embolism, are the major causes of death in developed countries. Several studies in twins and siblings have shown that genetic factors contribute significantly to the development of these diseases. Since the advent of molecular genetics in medicine, it has been a focus of interest to elucidate the role of mutations in various candidate genes and their impact on hemostatic disorders such as arterial and venous thromboses. In this article, we review the current knowledge of the contribution of polymorphisms in coagulation factors to the development of thrombotic diseases. We show that in arterial thrombosis, results are controversial. Only for factor XIII 34Leu a protective effect on the development of myocardial infarction has been demonstrated in several studies. No other single polymorphism in a coagulation factor could be confirmed as a relevant risk factor, although there is evidence for a role of factor V Arg506Gln, factor VII Arg353Gln, and vWF Thr789Ala polymorphisms in patient subgroups. Further studies will be necessary to confirm the value of testing for genetic polymorphisms in arterial thrombosis. A large body of data is available on the role of factor V Arg506Gln and the prothrombin G20210A mutation in venous thrombosis. Some papers already recommend diagnosis and treatment strategies. We will discuss these recent publications on venous thrombosis in our review.

Prospective study of the A455V polymorphism in the thrombomodulin gene, plasma thrombomodulin, and incidence of venous thromboembolism: the LITE Study

Plasma thrombomodulin (soluble TM; sTM) is considered to be a marker of endothelial injury, but a recent report indicated that the relationship of sTM with thrombosis is complex. Venous thromboembolic events were identified in adults in two longitudinal cohort studies, the Atherosclerosis Risk in Communities Study and the Cardiovascular Health Study, totaling 21 690 participants. After 8 years of follow-up, sTM was measured in baseline plasma of 305 participants who developed venous thrombosis and 607 who did not. Thrombomodulin A455V genotype was determined in 302 cases and 626 controls. There was no difference in the prevalence of the three TM genotypes between cases and controls and no difference in age-adjusted mean values of sTM by genotype. There were no associations of age-adjusted sTM or TMA455V genotype with overall venous thromboembolism or with thrombosis in any subtype of venous thromboembolism.

Fatal pulmonary arterial thrombosis associated with chlorine gas poisoning

We present a patient with accidental chlorine gas poisoning who died from pulmonary thrombosis due to a marked increase in hemostatic factors such as von Willebrand factor after recovering from the acute poisoning.

Fibrin monomer could be a useful predictor of pulmonary embolism after total hip arthroplasty: preliminary report

We examined 17 total hip arthroplasty patients in order to develop a method for the predictive diagnosis of pulmonary embolism (PE) after joint arthroplasty. Scintigraphy revealed the presence of PE in 4 patients. Prothrombin time (PT), activated partial thromboplastin time (aPTT), antithrombin III (ATIII), and thrombin-AT III complex (TAT) did not show significant differences between patients with and without PE. D-dimer 7 days after surgery showed significant differences between patients with and without PE. Fibrin monomer (FM) increased sharply after surgery, and it was significantly different between the patients with and without PE immediately after surgery and 2 days after surgery. Our findings suggest the importance of FM in the predictive diagnosis of pulmonary embolism after total hip arthroplasty, and 40 microg/ml or higher levels with our measurement method could represent a high-risk condition.

Changes of hemostatic molecular markers after gynecological surgery

The authors evaluated the hemostatic abnormalities occurring in the postoperative period of eight patients with malignant tumors and compared them with those occurring in the postoperative period of eight patients with benign tumors. Two of the patients with malignant tumor presented pulmonary embolism after operation. Plasma fibrinogen and fibrin degradation product levels in patients with malignant tumors were already high before operation and further increased significantly after operation. The plasma levels of D-dimer, thrombin-antithrombin complex, and free-tissue factor pathway inhibitor were increased in both groups after operation, but they were higher in patients with malignant tumors than in patients with benign tumors. The plasma levels of protein C and antithrombin were significantly decreased in both groups after operation. but they were significantly lower in patients with malignant tumors than in those with benign tumors. The decreased activity of protein C or antithrombin may be not only a risk factor of thrombotic disease, such as pulmonary embolism, but also the cause of thrombosis. In patients with malignant tumors, the operation time was significantly longer than that in patients with benign tumors. This long operative period might cause vascular endothelial cell injury which is reflected by the plasma levels of free-tissue factor pathway inhibitor, antithrombin, and protein C.