Takahiro Nakasaki

Activity and Antigen Levels of Thrombin-Activatable Fibrinolysis Inhibitor in Plasma of Patients With Disseminated Intravascular Coagulation

We measured the plasma levels of thrombin-activatable fibrinolysis inhibitor (TAFI) activity and antigen in patients with disseminated intravascular coagulation (DIC) to examine the relationship between hypofibrinolysis and the pathogenesis of DIC. TAFI activity and antigen levels in the plasma were both significantly low in patients with DIC. TAFI activity in plasma was correlated with TAFI antigen, indicating that activity and antigen correspond well. The decrease of TAFI activity in DIC may be due to enhanced consumption. Since the plasma thrombin-antithrombin III complex (TAT) level was found to be elevated in DIC, increase of thrombomodulin-thrombin complex generation is suggested in this state. TAFI activity and antigen levels were negatively correlated with TAT and D-dimer, suggesting that the plasma levels of TAFI are reduced by thrombin generation. Since TAFI was not correlated with fibrinogen, plasma-alpha(2)plasmin inhibitor complex (PPIC) and tissue type plasminogen activator/plasminogen activator inhibitor-1 (tPA/PAI-1) complex, TAFI might be a secondary modulator of fibrinolysis. The TAFI activity in plasma was significantly low in patients with infection and in those with organ failure, suggesting that TAFI may play an important role in the mechanism of organ failure in DIC-associated sepsis. In brief, TAFI may play an important role in the pathogenesis of DIC and organ failure.

Hemostatic Molecular Markers Before the Onset of Disseminated Intravascular Coagulation

We retrospectively measured various hemostatic markers in 240 patients with disseminated intravascular coagulation (DIC) before the onset of DIC and in 110 non‐DIC patients, and examined their usefulness for the diagnosis of pre‐DIC. Changes in prothrombin time ratio and fibrinogen levels were not significant before the onset of DIC. The plasma levels of fibrinogen and fibrin degradation products before the onset of DIC were increased and the platelet count was gradually reduced in nonleukemic patients; these changes were already significant in the non‐DIC state. The plasma levels of thrombin–antithrombin complex (TAT), plasmin–plasmin inhibitor complex (PPIC), D‐dimer, and soluble fibrin monomer (sFM) were increased before the onset of DIC. In leukemic patients, the plasma levels of sFM on day 5, those of TAT on day 3, and D‐dimer on day 1, were significantly increased before the onset of DIC. The levels of most hemostatic markers 7 days before the onset of DIC were not different from those observed in the non‐DIC state. In nonleukemic patients, only D‐dimer, sFM, and TAT levels were significantly increased 7 days before the onset of DIC compared with values in the non‐DIC state. The positive rate of hemostatic markers for the diagnosis of DIC, TAT, and PPIC were high during the pre‐DIC and non‐DIC groups. The plasma levels of sFM and D‐dimer were low in non‐DIC and increased gradually during the pre‐DIC state. These findings suggest that hemostatic molecular markers such as sFM, D‐dimer, and TAT are useful for the diagnosis of pre‐DIC, although their cutoff values were different among various diseases. Am. J. Hematol. 60:273–278, 1999.

Increased serum levels of thrombopoietin in patients with thrombotic thrombocytopenic purpura, idiopathic thrombocytopenic purpura, or disseminated intravascular coagulation

The serum levels of thrombopoietin (TPO) were measured in 16 patients with thrombotic thrombocytopenic purpura (TTP), 12 with hemolytic uremic syndrome (HUS), 10 with aplastic anemia (AA), 10 with disseminated intravascular coagulation (DIC), and 71 with idiopathic thrombocytopenic purpura (ITP). The serum TPO levels were measured with a sensitive sandwich enzyme-linked immunosorbent assay. The serum TPO level in the ITP group (1.68 ± 0.85 fmol/ml) were not significantly increased compared with those of the normal subjects. The TPO levels in the TTP (2.77 ± 1.38 fmol/ml) and HUS groups (5.77 ± 4.41 fmol/ml) were higher than those of the normal subjects. The patients with AA (12.7 ± 8.0 fmol/ml) and those with DIC (13.3 ± 5.7 mol/ml) had significantly higher serum TPO levels than did the normal subjects and ITP patients. The TPO levels were well correlated with the platelet counts in the TTP patients, and were negatively correlated with the platelet counts in the ITP patients. These results suggest that the serum TPO levels in some thrombocytopenic diseases are regulated not only by the platelet count and the megakaryocyte mass, but also by other factors.

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–α1‐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–α1‐AT complex. These data suggest that measurements of APC–PCI complex and APC–α1‐AT complex may be useful for the diagnosis of DIC. After treatment of DIC, the plasma levels of APC–PCI complex and APC–α1‐AT complex were significantly decreased, but not those of PCI. Plasma levels of thrombin–antithrombin complex (TAT), plasmin–α2‐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. Am. J. Hematol. 65:35–40, 2000.

Plasma Levels of Total Plasminogen Activator Inhibitor-I (PAI-I) and tPA/PAI-1 Complex in Patients With Disseminated Intravascular Coagulation and Thrombotic Thrombocytopenic Purpura

In this study, we examined changes in the plasma levels of total plasminogen activator inhibitor-I (PAI-I) and tissue-type plasminogen activator (tPA)/PAI-I complex in patients with disseminated intravascular coagulation (DIC) and in those with thrombotic thrombocytopenic purpura (TTP) to investigate the fibrinolytic function and its relation to organ failure, The plasma levels of total PAI-I and tPA/PAI-I complex were significantly higher in patients with DIC, pre-DIC, and TTP than in those with non-DIC. The plasma levels of thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), D-dimer, thrombomodulin (TM), total PAI-I, and tPA/PAI-I complex were significantly higher in patients with organ failure than in those without organ failure. The plasma levels of total PAI-I and tPA/PAI-I complex were markedly increased in patients with acute leukemia. The plasma levels of total PAI-1, but not those of tPA/PAI-I complex, were significantly increased in patients with sepsis or with solid cancer. In all cases, total PAI-I or tPA/PAI-I complex was not significantly correlated with any hemostatic marker. Measurement of total PAI-I and tPA/PAI-I complex may be useful in the diagnosis of DIC.

Changes in plasma tissue factor pathway inhibitor levels during the clinical course of disseminated intravascular coagulation

In healthy volunteers, the plasma total tissue factor pathway inhibitor (TFPI) level was 68.7 ± 14.1 ng/ml; the plasma free TFPI level, 17.7 ± 5.4 ng/ml; the lipoprotein-associated TFPI (LP-TFPI), 51.1 ± 12.0 ng/ml; the free TFPI/total TFPI ratio 0.26 ± 0.07; and the plasma tissue factor levels were 149 ± 46 pg/ml.Plasma tissue factor levels in patients with disseminated intravascular coagulation (DIC) were significantly higher than those in pre-DIC patients or in non-DIC patients. Plasma total-TFPI, free-TFPI and LP-TFPI levels were significantly higher in DIC patients than those in pre-DIC patients or in non-DIC patients. Before the onset of DIC, the plasma levels of tissue factor gradually increased, and 3 days before the onset of DIC they were significantly higher than those in non-DIC patients. The plasma levels of tissue factor reached their highest level 1 day before the onset of DIC and gradually decreased after the onset of DIC. Plasma levels of total-TFPI, free-TFPI, and LP-TFPI gradually increased before the onset of DIC, and the total-TFPI and LP-TFPI reached their highest levels at the onset of DIC. Plasma free-TFPI reached highest level one day after the onset of DIC. During the clinical course of DIC, the plasma level of tissue factor was the first to increase, then that of LP-TFPI and finally the free-TFPI plasma levels. These differences in the peak plasma levels of tissue factor, free-TFPI, and LP-TFPI might be related to the clinical course of DIC.

Increased Plasma Thrombomodulin as a Vascular Endothelial Cell Marker in Patients With Thrombotic Thrombocytopenic Purpura and Hemolytic Uremic Syndrome

Several hemostatic and vascular endothelial cell markers were measured in 39 patients with thrombotic thrombocytopenic purpura (TTP)/hemolytic uremic syndrome (HUS) and in 20 healthy volunteers to examine the relationship between the occurrence of hemostatic abnormality or vascular endothelial cell injury and patient outcome. The plasma levels of von Willebrand factor, tissue plasminogen activator (TPA), plasminogen activator inhibitor (PAI-1), and the TPA-PAI-1 complex were significantly increased in TTP/HUS patients; however, the levels of these markers were not significantly different between TTP/HUS patients who survived and those who died, suggesting that these markers might not be directly related to outcome. The plasma levels of soluble granule membrane protein (GMP)-140 were significantly higher in TTP/ HUS patients than in healthy volunteers, suggesting that platelets and vascular endothelial cells are activated or injured in TTP/HUS. There was no significant difference in GMP-140 levels between TTP/HUS patients with good and poor prognoses ; this may be owing to the release of GMP-140 from platelets. The plasma thrombomodulin (TM) levels in TTP/ HUS patients were significantly higher than in healthy volunteers; the plasma TM levels were significantly higher in patients who died than in patients who survived. These findings showed that TM levels reflect the outcome and that the outcome of TTP/HUS depends on the presence vascular endothelial cell injury. The plasma protein C and antithrombin levels were markedly reduced in TTP/HUS patients who died compared with those who survived. These findings suggest that reduced plasma antithrombin and protein C may be useful markers of systemic vascular endothelial injury. In conclusion, the results of this study showed that the outcome of TTP/HUS is related to vascular endothelial cell injury and that plasma TM, antithrombin, and protein C levels may be useful markers of systemic vascular endothelial cell injury.

Hemostatic Abnormalities in Patients With Thrombotic Complications on Maintenance Hemodialysis

Before hemodialysis (HD), plasma levels of tissue factor (TF), free-TF pathway inhibitor (TFPI) and thrombo modulin (TM) were significantly higher in patients with HD than in healthy volunteers. Plasma levels of (T-F) TFPI and plasmin plasmin inhibitor complex (PPIC) were significantly higher in patients with HD than in healthy volunteers. During HD, plasma levels of TF and (T-F) TFPI were not significantly increased, but plasma levels of total TFPI and free TFPI at 1 hour after and at the end of HD were significantly increased, compared with levels before start of HD. Plasma level of PPIC 1 hour after start of HD was significantly higher than before start of HD, and plasma levels of thrombin antithrombin com plex (TAT). PPIC. D-dimer. TM, and protein C (PC) at the end of HD were significantly higher than before start of HD. In patients with thrombosis complications, plasma TF levels were significantly higher than in patients without thrombotic com plications during HD. Plasma levels of PC were significantly lower in patients with thrombotic complications than in patients without thrombotic complications. There was no significant difference between both groups during HD in hemostatic pa rameters, with the exception of TF and PC. Hemostatic abnormalities existed in patients with HD; espe cially, increased TF and decreased PC might cause thrombotic complications.

Increased thrombopoietin levels in idiopathic thrombocytopenic purpura patients with a poor response to steroid therapy

The serum thrombopoietin (TPO) levels in 61 idiopathic thrombocytopenic purpura (ITP) patients were found to be slightly increased compared with those of 29 normal subjects. The TPO levels of the 15 ITP patients who had a poor response to steroid therapy (i.e. an unchanged platelet count) were higher than those of the 22 ITP patients who had a good response to steroid therapy (i.e. an increased platelet count) and the normal subjects. The TPO levels in the 15 ITP patients whose platelet count was higher than 10 x 10(4)/microl after the discontinuation of steroid therapy significantly higher than those of the normal subjects. The platelet-associated immunoglobulin G (PAIgG) levels in the ITP patients who had a poor response to steroid therapy were slightly increased compared with the normal subjects and the ITP patients who had a good response to the steroid therapy and the nine ITP patients who did not undergo the steroid therapy. The serum TPO level was negatively correlated only with the megakaryocyte count in the ITP patients, and the megakaryocyte count in the ITP patients who had good responses to the steroid therapy was higher than that in those who had poor responses. These data suggest that serum TPO levels might be important for the prediction of the outcome of ITP patients who receive steroid therapy.

Increased soluble fibrin monomer and soluble thrombomodulin levels in non-insulin-dependent diabetes mellitus.

We measured the plasma levels of fibrinogen, D-dimer, thrombin-antithrombin complex (TAT), plasmin-plasmin inhibitor complex (PPIC), soluble fibrin monomer (SFM), tissue-type plasminogen activator (t-PA) and thrombomodulin (TM) in patients with non-insulin-dependent diabetes mellitus (NIDDM). There were no significant differences in the hemostatic parameters between the 77 patients with NIDDM and healthy control subjects, although the plasma levels of fibrinogen, D-dimer, TAT, and PPIC in the NIDDM patients were slightly higher than those in the healthy controls. Among the NIDDM patients divided into three groups by the urinary albumin excretion (UAE) level, there was no significant difference in age or sex among the normo-, micro-, and macroalbuminuria groups, and the HbA1C level in the micro- and macroalbuminuria groups were slightly higher than those in the normoalbuminuria group. There was no significant difference in activated partial thromboplastin time, prothrombin time, fibrinogen, TAT, PPIC, D-dimer, or t-PA among these three groups. The plasma SFM and TM levels in the macroalbuminuria group were significantly higher than those in the normo- and microalbuminuria groups. The relationships between HbA1C and the hemostatic parameters were poor, but the plasma TM and SFM levels were significantly correlated with the urine albumin index.