Masahide Yamazaki

Prothrombin fragment F1+2 and thrombin-antithrombin III complex are useful markers of the hypercoagulable state in atrial fibrillation

It is well known that atrial fibrillation (AF) is one of the most important diseases that predispose patients to thrombosis. We have attempted to identify patients with AF in the hypercoagulable state by measuring molecular markers such as thrombin-antithrombin III complex (TAT) and prothrombin fragment 1 + 2 (PTF) and determining the effect of antithrombotic therapy on these markers; 83 patients with AF were studied. Increased levels of plasma TAT and PTF were more frequently observed in patients with AF and associated mitral stenosis than in patients with AF alone. In cases of AF without mitral stenosis, plasma levels of TAT and PTF were significantly lower in those patients receiving antithrombotic agents (aspirin or warfarin) than in those receiving no antithrombotic agents. Furthermore, plasma levels of PTF were significantly lower in patients given warfarin than in those receiving aspirin. These results suggest that (1) patients with AF and mitral stenosis who are not given warfarin are in an extremely hypercoagulable state and (2) some patients with AF without mitral stenosis who are not given antithrombotic agents are also moderately hypercoagulable. In vivo activation of blood coagulation was more effectively controlled in patients receiving warfarin than in those taking aspirin.

Hypercoagulability and high lipoprotein(a) levels in patients with type II diabetes mellitus

Diabetes mellitus is associated with disturbances in hemostasis that could contribute to the development of diabetic vascular disease. We investigated the changes in parameters of blood coagulation and the fibrinolytic system and in plasma levels of lipoprotein(a)(Lp(a)) in 124 patients with type II diabetes mellitus and 44 healthy control subjects matched for age and body mass index (BMI) to determine whether hemostatic disturbances may lead to increased cardiovascular mortality. Median levels of fibrinogen (P < 0.0001), thrombin-antithrombin III complex (TAT) (P < 0.005), and plasminogen activator inhibitor-1 (PAI-1) activity (P < 0.05) in plasma were significantly elevated in diabetic patients compared with controls. The median concentration of Lp(a) was significantly higher in diabetic patients than in normal controls (18.2 vs. 12.6 mg/dl. P < 0.0005). Lp(a) levels tended to be elevated in patients with a prolonged history of diabetes. There was no evidence that Lp(a) levels were affected by metabolic control or by type of treatment. Twenty-two diabetics with coronary heart disease (CHD) had significantly higher levels of fibrinogen (P < 0.05), TAT (P < 0.05), and Lp(a) (24.7 vs. 13.7 mg/dl, P < 0.01) than the 51 patients without diabetic angiopathy. Our data indicate that impaired hemostatic balance in diabetes may cause hypercoagulability and may thus contribute to the increased cardiovascular mortality in diabetes.

An enhanced fibrinolysis prevents the development of multiple organ failure in disseminated intravascular coagulation in spite of much activation of blood coagulation

Objectives To investigate the relationship between fibrinolytic enhancement and the development of multiple organ failure (MOF) in disseminated intravascular coagulation (DIC). To detect the useful prognostic index for outcome in DIC. Design Case-control study. Setting A department of internal medicine in a university hospital, a clinical division for diagnosis and treatment, mainly of respiratory diseases, hematologic diseases, DIC, and other diseases requiring critical care medicine. Patients A total of 69 DIC patients, 31 with MOF. Interventions None. Measurement and Main Results The DIC patients with MOF had more elevated levels of tissue plasminogen activator antigen (t-PA) and plasminogen activator inhibitor antigen (PAI), and more depressed levels of plasmin-&agr;2 plasmin inhibitor complex (PIC) and fibrin/fibrinogen degradation products than those without MOF, although no significant difference in thrombin-antithrombin complex (TAT) levels was observed. A fibrinolytic enhancement (shown by PIC) was parallel to an activation of blood coagulation (shown by TAT) in DIC patients without MOF, although no such fibrinolytic enhancement was provoked even by much activation of blood coagulation in DIC patients with MOF. Whereas all the patients without MOF were restored from DIC, 14 of 31 patients with MOF were unable to be restored from DIC and died. A significant increase in plasma levels of t-PA and PAI under the condition of sustained hemostatic activation was observed in the patients who died. Conclusion Enhanced fibrinolysis was considered to be the important defense mechanism in preventing the development of MOF in DIC. The increases in plasma levels of t-PA and PAI were poor prognostic markers in DIC. Further careful study may be useful to clarify whether the fibrinolytic therapy is beneficial in clinical DIC patients with MOF.

Decreased plasma activity of antithrombin or protein C is not due to consumption coagulopathy in septic patients with disseminated intravascular coagulation

Abstract: We investigated whether depressed plasma antithrombin and protein C activity, considered as a specific finding of disseminated intravascular coagulation (DIC), is due to consumption coagulopathy in septic patients with DIC. An analysis of hemostatic parameters was performed in 139 septic patients (68 with DIC and 71 without DIC). Plasma activity of antithrombin and protein C tended to be significantly decreased in septic patients with DIC but not in those without DIC (p < 0.001). However, when the septic patients were classified into three groups according to the albumin (or choline esterase) level, no significant differences in antithrombin activity or protein C activity were observed between the patients with and without DIC in any of the subgroups. Notably, neither the plasma activity of antithrombin nor protein C was decreased even in septic patients with DIC who had normal plasma levels of albumin (or choline esterase). No significant correlation was observed between plasma levels of thrombin–antithrombin complex (TAT) and antithrombin activity, or between plasma levels of TAT and protein C activity either in septic patients with DIC or without DIC. It is reasonable to conclude that the markedly reduced plasma activity of antithrombin and protein C is not due to consumption coagulopathy in septic patients with DIC.

Transient lupus anticoagulant induced by Epstein-Barr virus infection.

A 25-year-old woman presented with an episode of left calf deep vein thrombosis and pulmonary thrombosis. She was found to have a lupus anticoagulant with anticardiolipin antibodies, some autoimmune antibodies and antibodies for primary Epstein-Barr (EB) virus infection. Six months later, lupus anticoagulant and other autoimmune antibodies were found to be negative and EB virus antibodies were shown to be seroconverted. We suggest that the transient presence of lupus anticoagulant was due to EB virus infection caused by activation of polyclonal B-lymphocytes.

Pathophysiology of disseminated intravascular coagulation (DIC) progresses at a different rate in tissue factor-induced and lipopolysaccharide-induced DIC models in rats

&NA; Tissue factor (TF) and lipopolysaccharide (LPS) are frequently used to induce disseminated intravascular coagulation (DIC) in experimental animal models. Although the pathophysiology of DIC may differ depending on which agent is used for induction, previous studies on models of DIC have not distinguished which DIC‐inducing agent was used. In the present paper, we evaluate the characteristics of TF‐induced and LPS‐induced DIC using two types of DIC models, with special reference to selected hemostatic parameters and pathological findings within the kidney. Male Wistar rats were administered TF (3.75 U/kg; sustained infusion for 4 h) or LPS (30 mg/kg; sustained infusion for 4 h) via the tail vein, and blood sampling was performed at 0, 1, 3, 4, 5, 7, 9, 11, and 28 h. Judging from changes in the levels of thrombin‐antithrombin complex, fibrinogen levels, and platelet counts, it is reasonable to conclude that the severity of both types of experimental DIC is similar with regard to hemostatic activation and consumption coagulopathy. A marked elevation in the level of D‐dimer was noted without any organ dysfunction or much fibrin deposition in the kidney upon administration of TF. However, a markedly prolonged period of elevation in plasminogen activator inibitor activity, a prolonged depression in antithrombin III activity, severe organ failure, and a markedly prolonged period of fibrin deposition in the kidney was observed following LPS administration. A modest number of the rats from the TF‐induced DIC model died during the experimental period, whereas a large number of rats died during LPS‐induced DIC, especially after 9 h. Since the time course of the pathophysiology differed remarkably among the TF‐induced and LPSinduced DIC models in rats, we recommend that TFinduced and LPS‐induced DIC be approached as distinct models in order to determine the implications of their experimental and clinical use. Blood Coagul Fibrinolysis 14:221‐228

Elevated anti-annexin V antibody levels in antiphospholipid syndrome and their involvement in antiphospholipid antibody specificities.

To clarify the involvement of annexin V (ANX) in antiphospholipid antibody (APA) specificities, we studied antiANX antibodies (aANX) using 2 kinds of enzyme-linked immunosorbent assay plates (plain and gamma-irradiated) and anti-beta 2-glycoprotein I antibodies (a-beta 2GPI) in 53 patients with antiphospholipid syndrome (APS). The incidence of aANX IgG-positive results in the autoimmune APS group was significantly higher than that of healthy control subjects. However, we could not demonstrate a significantly higher incidence in the infection- or drug-induced group. Nor could we find an increased incidence of IgM isotype. When the 2 plates were compared, the discrepancies of positivity were demonstrated in both isotypes. We speculated that these discrepancies between the plate surfaces were attributed to the altered antigenicity of ANX. Although positivity of a-beta 2GPI was associated significantly with clinical manifestations, no significant associations were demonstrated between the incidence of aANX-positive results and clinical manifestations. We inferred that the involvement of aANX in the pathogenic mechanism of APS is unlikely.

Study of the balance between coagulation and fibrinolysis in disseminated intravascular coagulation using molecular markers.

Plasma levels of thrombin-antithrombin III complex (TAT), plasmin-alpha 2-plasmin inhibitor complex (PIC) and active plasminogen activator inhibitor (PAI) were assayed in 66 cases of disseminated intravascular coagulation (DIC). Significant elevation of both TAT and PIC was observed in all cases of DIC. Most elevated levels of TAT were seen in DIC with acute promyelocytic leukaemia (APL) and sepsis. The highest levels of PIC were seen in DIC with APL but were much lower in sepsis. A significant elevation in active PAI was observed in DIC due to acute leukaemia (apart from APL), chronic myeloid leukaemia and sepsis, but not in APL, non-Hodgkin lymphoma and cancer. Active PAI was higher in patients with multiple organ failure (MOF) than in those without MOF while PIC was lower in patients with this complication. Thus, the balance of coagulation and fibrinolysis varied according to the underlying cause of DIC; APL had more dominant activation of fibrinolysis, while sepsis had greater activation of coagulation. It is suggested that the inhibition of secondary fibrinolytic activation plays an important role in the progression of MOF by the disturbance of the microcirculation.

Marked difference in pathophysiology between tissue factor- and lipopolysaccharide-induced disseminated intravascular coagulation models in rats

Objective Tissue factor and lipopolysaccharide frequently have been used to induce disseminated intravascular coagulation in experimental animal models. Although the pathophysiology of disseminated intravascular coagulation may differ according to the agents used to induce it, these previous models have not distinguished between the use of different disseminated intravascular coagulation-inducing agents. In this study, we attempted to evaluate the characteristic features of these agents in two types of disseminated intravascular coagulation models, with special reference to selected hemostatic parameters and pathologic findings in the kidney. Design Prospective, comparative, experimental study. Setting Laboratory at a university hospital. Subjects Twenty-seven male Wistar rats, age 6–7 wks, weighing 160–170 g. Interventions Three groups of animals were studied: a control group (n = 8) receiving physiologic saline, a tissue factor-treated group (n = 11) receiving tissue factor 3.75 units/kg, and a lipopolysaccharide-treated group (n = 8) receiving lipopolysaccharide 30 mg/kg; each group sustained infusion for 4 hrs via the tail vein. Measurements and Main Results The degree of hemostatic activation in both types of experimental disseminated intravascular coagulation was identical, based on the results of thrombin-antithrombin III complex levels. Markedly elevated D-dimer concentrations were observed without organ dysfunction or fibrin deposition in the kidney on administration of tissue factor, whereas markedly elevated plasminogen activator inhibitor activity, decreased antithrombin III activity, severe organ failure, and marked fibrin deposition in the kidney were observed for lipopolysaccharide administration. Conclusion Because pathophysiology differed remarkably between the tissue factor- and lipopolysaccharide-induced disseminated intravascular coagulation models in rats, we recommend that they be assessed carefully as distinct entities to determine implications of their experimental and clinical use.

High titer of serum antiphospholipid antibody levels in adult Henoch-Schönlein purpura and cutaneous leukocytoclastic angiitis

OBJECTIVE To investigate a possible role of antiphospholipid (aPL) antibodies in adult Henoch-Schönlein purpura (HSP) and cutaneous leukocytoclastic angiitis (CLA). METHODS We reviewed the records of 30 HSP and 8 CLA adults with an initial cutaneous manifestation of palpable purpura on their lower extremities between 2003 and 2007. Eight microscopic polyangiitis (MPA) patients and 30 healthy persons were recruited as controls. Serum anticardiolipin (aCL), anti-phosphatidylserine-prothrombin complex (anti-PS/PT), and anti-beta(2)-glycoprotein I (anti-beta(2)GPI) antibody levels in HSP, CLA, MPA patients, and healthy controls were measured by enzyme-linked immunosorbent assay. RESULTS Twenty-two HSP patients (73%) were positive for serum IgA aCL antibodies. Nineteen (63%) had IgA anti-PS/PT antibodies and 4 (13%) had IgA anti-beta(2)GPI antibodies. IgA aCL and anti-PS/PT antibodies showed a significant correlation (P = 0.007). Twenty (67%) HSP patients had IgM anti-PS/PT antibodies and 6 (20%) had IgG anti-PS/PT antibodies. Six (75%) CLA patients had IgM anti-PS/PT antibodies and 2 (25%) had IgG anti-PS/PT antibodies. In contrast, aPL antibodies were not found in any MPA patients or normal controls. Serum IgA aCL antibody levels in HSP patients showed a significant correlation with serum IgA and C-reactive protein (CRP) levels (P = 0.030 and 0.039, respectively). A positive correlation between CRP and serum IgA anti-PS/PT antibody levels was observed in HSP patients (P = 0.023). Serum IgA aCL antibody levels were also significantly associated with proteinuria according to urinalysis (P = 0.024). CONCLUSION Serum levels of IgA aCL and anti-PS/PT antibodies were elevated in adult HSP, suggesting that serum IgA antibodies may play some role in adult HSP. IgA aCL and/or anti-PS/PT antibodies could serve as markers for adult HSP and should be monitored as an indicator of adult HSP activity. Small-vessel vasculitis could be dependently associated with the presence of IgM anti-PS/PT antibodies. These findings suggest that aPL antibodies are closely related to the pathogenic factors that trigger the development of vasculitis.