Changes in hemostatic and fibrinolytic proteins in patients receiving L-asparaginase therapy

Hemostatic changes were evaluated in ten patients with acute lymphoblastic leukemia and lymphoma who received chemotherapy with L-asparaginase, vincristine, and prednisolone for 1 week. Following treatment, prothrombin time and activated partial thromboplastin time were significantly prolonged, while a marked decrease in fibrinogen levels was observed. The values for cross-linked fibrin degradation products, however, remained within normal limits during treatment, which excluded the possibility of disseminated intravascular coagulation. The concentrations of coagulation inhibitors (antithrombin III, protein C, and protein S), plasminogen, and alpha 2 antiplasmin also significantly decreased; however, levels of both tissue-type plasminogen activator and plasminogen activator inhibitor, which are synthesized in endothelial cells, increased during the treatment. Although a decrease was observed in concentrations of many coagulation factors, including subunits A and B of factor XIII, the activity and antigenicity of factor VII significantly increased following the treatment. From this study, we concluded that these hemostatic abnormalities caused by the administration of L-asparaginase produced a labile condition that easily inclines to bleeding or thrombosis.     

Coagulation Studies in Patients with Acute Infectious Hepatitis

Coagulation studies were performed on 104 hospital inpatients with acute infectious hepatitis. Patients with clinical evidence of liver failure were studied separately from those without liver failure.
A coagulation defect was found in 57 of the 78 patients without liver failure. This consisted of a prolonged prothrombin time and reduced levels of factors V, VII and X, and plasminogen. The defect was mild in most patients and was not associated with bleeding. A severe coagulation defect was found in all 26 patients with liver failure. Factors II, V, VII and X were markedly reduced. Plasminogen was reduced in all patients, and a low plasma fibrinogen concentration and thrombo-cytopenia were found in half. One third of the patients studied showed an increase in serum fibrin/ fibrinogen degradation products. It is suggested that in some of these patients disseminated intravascular thrombosis contributed to the coagulation defect. Two patients had evidence of increased fibrinolytic activity.
Bleeding occurred in 15 patients with liver failure and required treatment in 10. Fifteen patients with liver failure died. Nine patients with liver failure were treated with exchange transfusions during which a significant improvement of the prothrombin time and a slight reduction in platelet count was observed. Bleeding stopped during exchange transfusions in six of eight patients. It is possible that the improvement of the coagulation defect during exchange transfusions contributed to improved haemostasis.     

Fibrinolysis during liver transplantation in humans: role of tissue- type plasminogen activator

Human liver transplantation is frequently associated with a coagulopathy and bleeding diathesis developing during the anhepatic phase of surgery. The hemostatic defect has been attributed in part to accelerated fibrinolysis. In this study we evaluated changes in specific blood fibrinolytic parameters occurring in eight adult patients undergoing first-time orthotopic liver transplantation. Five of the eight patients experienced moderate to severe systemic fibrinolysis as reflected by alpha 2-antiplasmin consumption and fibrinogen degradation with the concomitant appearance of fibrin(ogen) degradation products. In association with these changes, an increase in tissue-type plasminogen activator (t-PA) activity and t-PA antigen levels was also observed. Fibrinolysis was most pronounced during the anhepatic phase of surgery and decreased after revascularization of the grafted liver. Three additional patients who underwent the same procedure manifested much less evidence of systemic fibrinolytic activation and had minimal elevation of t-PA antigen levels or activity. Urokinase-type plasminogen activator levels, although elevated in three patients, were disassociated from increased t-PA levels and concomitant systemic fibrinolysis. The operative course of those patients developing t-PA-associated fibrinolysis was characterized by shock, acidosis, generalized bleeding, and a need for substantially greater blood product support during surgery. These findings suggest that the observed fibrinolytic defect is related to increased circulating plasma levels of t-PA, presumably resulting from a combination of increased intravascular release and decreased hepatic clearance of t-PA. These observations may have implications for intraoperative therapy for the transplant-related coagulopathy and its associated bleeding.     

Fibrinolysis at Rest and after Exercise in Hepatic Cirrhosis

S ummary . A study of the fibrinolytic enzyme system in 37 cirrhotic patients at rest and 15 cirrhotic patients following a treadmill exercise procedure is reported. An outstanding feature of the resting studies was a significant elevation in the levels of plasma plasminogen activator and serum fibrin/fibrinogen degradation products, when compared to age and sex-matched healthy controls. Moreover, there was a significant positive correlation between those two fibrinolytic parameters. No significant difference was demonstrated between the control and cirrhotic groups in relation to plasma fibrinogen, euglobulin plasminogen and plasma urokinase inhibitor activity. The exercise studies showed that following an entirely physiological stimulus the plasminogen activator response in some cirrhotics was excessive in terms of either the initial response and/or prolongation of the recovery period. However, an exaggerated initial response was not necessarily followed by a prolongation recovery period nor was a relationship established between the resting levels of plasminogen and an abnormal exercise response. Furthermore, there was no correlation between the increases in plasminogen activator and serum fibrin/ fibrinogen degradation products following exercise.     

Activation of endothelium by immunotherapy with interleukin-2 in patients with malignant disorders

Treatment with intravenous recombinant human interleukin-2 (rh IL-2) is frequently accompanied by the capillary leak syndrome and disturbances of the coagulation system. Although the exact mechanisms are still not fully understood, the involvement of the endothelium is proven. This investigation aimed to elucidate more precisely the role of the endothelium in the generation of IL-2-based side-effects. In nine tumour patients receiving intravenous rh IL-2, parameters characterizing endothelial cell activation as well as activation of the coagulation system were evaluated. A significant increase of the circulating endothelial leucocyte adhesion molecule-1 (cELAM-1) and the vasoconstrictor peptide endothelin-1 (ET-1) was observed (P<0.05), indicating activation of endothelial cells. The simultaneous increase of tissue-plasminogen activator and plasminogen activator inhibitor type-1 during therapy (P<0.05) corroborated this observation. A decrease in platelet count parallelled by an increase of fibrin degradation products, the prolongation of partial thromboplastin time, and the decrease of fibrinogen (P<0.05) suggested the development of disseminated intravascular coagulation (DIC), induced by activated endothelium and intensified by transient hepatic failure. We concluded that activation of the endothelium mediated by IL-2 was accompanied by a loss of endothelial integrity and capillary leak. The activated endothelium can trigger DIC via activation of the coagulation cascade. The increased ET-1 might act as an endogenous counter-regulator of the disadvantageous haemodynamic side-effects induced by IL-2.     

Hemostasis and fibrinolysis in severe liver failure and their relation to hemorrhage

In a study of severe, decompensated liver failure, we tried to find a correlation between hemorrhage and parameters of hemostasis and fibrinolysis. Three groups of patients were studied: alcoholic cirrhosis; nonalcoholic cirrhosis, and acute liver failure without known prior liver disease. The two cirrhotic groups did not differ significantly from each other in coagulation or in fibrinolytic parameters, although liver function was more impaired in nonalcoholic cirrhosis. The levels of clotting factors, antithrombin III, prekallikrein, plasminogen and alpha 2-antiplasmin were significantly lower in the third group. Mean values of fibrinolytic activity (fibrin plate method) were slightly reduced as compared to normal in all three groups. Tissue plasminogen activator-related antigen tended to be elevated especially in alcoholic cirrhosis. The free fast-acting plasminogen activator inhibitor showed extremely high and extremely low levels in some patients among all three groups. Nonvariceal, capillary-type bleeding, including mucosal bleeding, hematomas and bleeding from puncture sites correlated with low thrombotest and normotest levels (p less than 0.01), low fibrinogen concentration (p less than 0.05) and with a high quotient of fibrinolytic activity (square root of lysis area) and normotest (p less than 0.001). The ratio between fibrin formation and dissolution appears to be an important parameter of hemorrhagic tendency in liver disease. Variceal bleeding appeared not to be related to impairment of hemostasis or fibrinolysis.     

Disturbances of blood coagulation associated with Salmonella typhi infections

Disturbances of blood coagulation were studied in 32 consecutive patients with typhoid fever on their admission to hospital. Estimations of prothrombin time, activated partial thromboplastin time, fibrinogen, fibrin degradation products (FDPs), factors VII, VIII and XII, alpha I antitrypsin, plasminogen, CI esterase inhibitor, and platelet counts were performed as well as liver function tests and blood counts. Five patients had laboratory evidence of disseminated intravascular coagulation (DIC) and two had a generalised bleeding disorder which in the other three was inapparent. The platelet count in the group as a whole was low (P less than 0.05) and the FDPs in most cases were mildly elevated. The pre-kallikrein values were depressed in three of the five with DIC, whereas factor XII was not reduced. These results indicate that bleeding disorders in typhoid fever are uncommon. The depression of pre-kallikrein indicates that the DIC is probably triggered by activation of the intrinsic coagulation pathway. Most patients had lymphopenia and monocytopenia but only two had neutropenia.     

Intravascular Coagulation in Acute Leukemia: Clinical and Subclinical Abnormalities

Fifteen patients with acute leukemiawere found to have evidence of ageneralized hemostatic disorder.These patients could be divided intothree groups. The first group consistedof three patients with increased fibrinogen catabolism without clinical orlaboratory evidence of intravascularcoagulation. The second group of fivepatients had laboratory evidence ofintravascular coagulation withoutclinically evident bleeding or thrombosis. The third group of seven patients developed symptomatic intravascular coagulation characterizedby bleeding, renal failure, and poorresponse to platelet transfusions.Laboratory evidence for intravascularcoagulation in these patients includedfalling plasma fibrinogen and factor Vlevels and elevated serum levels offibrinogen degradation products.Heparin therapy resulted in clinicalimprovement in all seven patients.Rising plasma fibrinogen and factorV levels correlated with a beneficialclinical response to heparin. Increasedfibrinogen catabolism, asymptomaticintravascular coagulation, and symptomatic intravascular coagulation formpart of a spectrum of generalizedhemostatic disorders in acute leukemia.

Submitted on February 29, 1972 Revised on May 10, 1972 Accepted on May 17, 1972     

Coagulation abnormalities in rheumatoid disease

Forty-one patients with rheumatoid arthritis, including 6 with acute vasculitis, 13 with chronic vasculitis, and 22 without vasculitis, were studied for evidence of intravascular coagulation and fibrinolysis (ICF). The mean plasma fibrinogen levels were elevated in all groups. The fibrinogen, platelet count, and fibrin split products were usually elevated in acute vasculitis. Fewer patients on corticosteroids had abnormal coagulation tests. Active plasmin was detected in 12 patients primarily with chronic vasculitis. Plasminogen activator activity was not diminished in vascular endothelium of normal appearing skin of those patients with or without vasculitis. None of the patients demonstrated decompensated intravascular coagulation and fibrinolysis. The results suggest over-compensated ICF occurring in rheumatoid arthritis, but rheumatoid patients with vasculitis cannot be clearly distinguished from those without vasculitis on the basis of the usual tests performed for coagulation and fibrinolysis abnormalities.     

Disseminated intravascular coagulation in sepsis.

Disseminated intravascular coagulation (DIC) has been considered a rather rare syndrome characterized by severe bleeding. In fact, both of these beliefs are wrong. Bleeding is fairly rare in DIC. The clotting parameters are usually normal unless the DIC is fulminating. It is usually thought that fibrinogen may be low or absent in DIC. However, afibrinogenemia is rare. Fibrinogen is usually high in DIC because of the high rate of fibrinogen manufacture by the liver in response to stress. DIC is very common and most cases are never diagnosed. This is because it has been hard to find fibrin thrombi in autopsy cases and because acute severe bleeding is uncommon. The reason fibrin thrombi are rare may be because they have been lysed by endogenous fibrinolytic enzymes before the autopsy. The appearance of endogenous fibrinolytic response could be a defense mechanism to lyse the microclots of DIC. In fact, this response is often successful. This defense can be aided by the administration of plasminogen activators that will lyse the clots. Heparin has been used for the treatment of DIC but has proved useless and is, in fact, dangerous. This is because heparin will not dissolve clots and may actually promote platelet agglutination. Administration of plasminogen activators will actually prevent bleeding diathesis.     

Diagnostic efficacy of six plasma proteins in evaluating consumptive coagulopathies. Use of receiver operating characteristic curves to compare antithrombin III, plasminogen, alpha 2-plasmin inhibitor, fibronectin, prothrombin, and protein C

Six coagulation proteins were measured in 79 consecutive patients referred to the coagulation service for suspected disseminated intravascular coagulation. Antithrombin III, plasminogen, and alpha 2-plasmin inhibitor were measured with fluorescent substrate assays. Fibronectin, prothrombin, and protein C were measured with electroimmunoassays. Using history and physical findings and the results of a coagulation screen (prothrombin time, partial thromboplastin time, fibrinogen, fibrin[ogen] degradation products, platelet count, and peripheral smear), the 79 patients were classified into five categories: no disseminated intravascular coagulation (n = 21), elevated fibrin(ogen) degradation products without other evidence of coagulopathy (n = 44), defibrination syndrome (n = 9), microangiopathic thrombocytopenic purpura (n = 4), and primary fibrinolysis (n = 1). Because the sensitivity and specificity of each of the proteins could not easily be compared, receiver operating characteristic (ROC) curves and areas under the ROC curves were calculated for each of the six proteins as well as for the tests of the coagulation screen. The ROC curves indicated that, apart from plasminogen, the other coagulation proteins provided little additional information about the classification of the coagulopathy.     

Mechanism of defibrination in humans after envenomation by the eastern diamondback rattlesnake

We prospectively studied the hemostatic system of ten persons bitten by the Eastern diamondback rattlesnake (Crotalus adamanteus) during 1978–1980. Blood was drawn when the patients arrived in the emergency room and every 6 hr thereafter. All envenomated victims developed incoagulable blood (defined by a thrombin time ≥ 120 sec, normal < 20 sec). Platelet counts and plasma levels of antithrombin III and factors II and VIII were not drastically altered, which distinguished this disorder from classic disseminated intravascular coagulation. Fibrinogen levels were markedly decreased (mean coagulable level of 0 mg/dl and antigenic levels of 99 mg/dl). Plasminogen levels were 20% of normal, alpha-2-plasminogen inhibitor was 17% of normal, and plasminogen activator was 20 times normal. Levels of fibrin degradation products peaked at a mean of 7,680 μg/ml. The magnitude and duration of the coagulopathy were proportional to the clinical severity of envenomation. Treatment with antivenin blunted the coagulopathy. Because venom from the Eastern diamond-back rattlesnake does not directly activate plasminogen, we conclude that coagulopathy following envenomation by that reptile appears to be due to partial proteolysis of fibrinogen with secondary activation of plasminogen by released plasminogen activator, probably of endothelial orgin.     

Characterization of the fibrinolytic state by measuring stable cross-linked fibrin degradation products in disseminated intravascular coagulation associated with acute promyelocytic leukemia

Plasma samples from patients with disseminated intravascular coagulation (DIC) associated with acute promyelocytic leukemia (APL) exhibited higher levels of the D-fragment of fibrin and fibrinogen degradation products [FDP(D)], with relatively lower levels of cross-linked fibrin degradation products (XDP), than samples of DIC with non-APL. The difference between FDP(D) and XDP levels increased only when alpha 2-plasmin inhibitor (alpha 2-PI) fell below 60% of the normal level in APL patients. These findings suggest that fibrinogenolysis occurs in APL patients when the alpha 2-PI level has decreased significantly.     

Plasmin generation and fibrin(ogen)olysis following desmopressin infusion.

Desmopressin acetate (DDAVP) is known to stimulate the release of tissue-type plasminogen activator (t-PA) from endothelial cells, but it is unclear whether the increased t-PA actually elicits the plasmin generation and fibrin(ogen)olysis in the circulating blood. We measured plasma levels of plasmin-alpha 2-plasmin inhibitor complex, fibrinogen degradation products (FgDP) and fibrin degradation products (FbDP) following desmopressin infusion in 19 patients with bleeding disorders or thrombophilia. Administration of desmopressin (0.3-0.4 microgram/kg) produced a 4.0-fold increase in plasmin-alpha 2-plasmin inhibitor complex at 30 min, whereas neither FgDP nor FbDP was elevated significantly. These findings indicate that desmopressin infusion provokes the generation of plasmin in vivo, but most of the plasmin generated is complexed to alpha 2-plasmin inhibitor and does not degradate fibrin or fibrinogen.     

Microembolism Syndrome: Acute Respiratory Failure and Disseminated Intravascular Coagulation

Summary: Haematological studies were performed in thirteen patients with acute respiratory failure secondary to trauma (10 cases), or other causes in which clinical features suggesting disseminated intravascular coagulation were present including shock, haemorrhagic manifestations and central nervous system, renal, endocrine and hepatic dysfunction. In the four fatal cases features of intravascular clotting shown at autopsy included focal haemorrhages, thrombi and infarcts.
Thrombocytopenia, decreased factor II levels and elevated fibrin split products were observed in all patients. Levels of other coagulation factors varied but serial changes followed a pattern characteristic of disseminated intravascular coagulation. Ten patients had low levels of plasminogen initially. Serial thrombin times were not greatly prolonged and euglobulin lysis times were lengthened. Red cell fragmentation and progressive anaemia in all cases, combined with either a decrease in haptoglobin or a rise in plasma haemoglobin in nine patients, provided evidence of microangiopathic haemolysis. β ₁A-globulin (C'3) was sub-normal in nine of twelve patients studied.
These data demonstrate disseminated intravascular coagulation leading to secondary fibrinolysis, microangiopathic haemolysis and, apparently, complement activation. In the light of both clinical and experimental observations, disseminated intravascular coagulation is an important pathogenic mechanism in acute respiratory failure of diverse aetiologies, and explains many of its features.     

Antithrombin III, plasminogen and alpha 2 antiplasmin in jaundice. Clinical usefulness and prognostic significance.

In this prospective study, antithrombin III, plasminogen and alpha 2 antiplasmin which are synthetised by the liver were measured and compared with the Normotest, Thrombotest and fibrinogen concentrations in 92 consecutive jaundiced patients. Antithrombin III appeared to be the most discriminant coagulation test in differentiating hepatocellular from cholestatic jaundice. A high correlation was observed between antithrombin III, plasminogen and alpha 2 antiplasmin values suggesting that the liver synthesis of these parameters was closely linked. The prognostic significance of the blood coagulation tests in patients with jaundice has been studied. In parenchymatous liver disease, antithrombin III, plasminogen and alpha 2 antiplasmin were superior to the Normotest, Thrombotest and fibrinogen concentrations in predicting the prognosis of the patients at the time of admission. In cholestatic jaundice, however, none of the blood coagulation tests studied had a prognostic significance.     

Effect of Fibrin Degradation Products and Thrombin on Fibrinogen Synthesis

The effect of intravenous administration of homologous fibrin degradation products and thrombin on fibrinogen synthesis was assessed in rabbits. The relative fibrinogen synthesis rate was calculated as a ratio of the amount of radiolabelled lysine incorporated into fibrinogen to the amount incorporated into albumin during the same measurement period. An increase in this ratio above control would indicate a relatively specific stimulation of fibrinogen synthesis as compared with albumin, which is not an acute-phase reactant. Injection of 45 mg of 'early' or 'late' fibrin degradation products failed to produce a significant increase in the relative fibrinogen synthesis rate, suggesting that fibrin degradation products play no feedback role in controlling fibrinogen synthesis. Infusion of small amounts of homologous thrombin (15--25 NIH u) was followed by a small but statistically significant elevation of the relative fibrinogen synthesis rate. This was not accompanied by any increase in the levels of fibrinogen degradation products in plasma, or by any decrease in plasma fibrinogen concentration, possibly suggesting that thrombin can stimulate fibrinogen synthesis by a mechanism independent of significant fibrinogenolysis or intravascular coagulation.     

Excessive fibrinolysis in suspected amyloidosis: demonstration of plasmin-alpha 2-plasmin inhibitor complex and von Willebrand factor fragment in plasma

We performed a hemostatic evaluation in detail in a patient with suspected amyloidosis who was suffering from several bleeding episodes. He had a shortened euglobulin clot lysis time, decreased alpha 2-plasmin inhibitor (alpha 2-PI), decreased plasminogen, elevated tissue-type plasminogen activator (t-PA), elevated plasmin-alpha 2-PI complex, and decreased ratio of ristocetin cofactor to von Willebrand factor (vWF) antigen. Fibrinogen and fibrin/fibrinogen degradation products levels fluctuated, with abnormal values on several occasions. On crossed immunoelectrophoresis, plasmin-alpha 2-PI complex and vWF fragment were demonstrated in the patient plasma. These abnormal findings and bleeding symptoms improved following the administration of tranexamic acid. Discontinuation of tranexamic acid resulted in deterioration of these parameters. These observations indicate that pathologic fibrinolysis (continuous intravascular plasmin generation) characterized by the consumption of alpha 2-PI and plasminogen, formation of plasmin-alpha 2-PI complex, and fragmentation of vWF contributed to the bleeding in this patient. It is important to recognize excessive fibrinolysis as the underlying cause of bleeding in these patients, since specific treatment with antifibrinolytic agents is effective in controlling the bleeding.     

Thrombin activation and increased fibrinolysis in patients with chronic liver disease

The respective roles of intravascular coagulation (DIC) and fibrinolysis were assessed in severe chronic liver disease by measuring thrombin-antithrombin (TAT) complexes, tissue-type plasminogen activator antigen (tPA Ag) and fibrinogen and fibrin degradation products (FgDP and FbDP respectively) in 66 patients with liver disease caused by cirrhosis (n = 34) or chronic hepatitis (n = 32) as compared to findings in a control group (n = 30). There was a significant increase of TAT complexes (P less than 0.01), tPA Ag (P less than 0.002), FDP and FbDP (P less than 0.001) in patients as compared to controls. FbDP increase was more evident in patients with cirrhosis than in those with hepatitis (P less than 0.01). Significant correlations between these parameters with some liver function tests were also demonstrated. Thus, in patients with severe liver disease, an increased thrombin activity, as demonstrated by high TAT levels; followed by hyperfibrinolysis suggest that a low grade DIC may occur.     

Recombinant tissue plasminogen activator in acute myocardial infarction in the Chinese in Hong Kong.

Eighty-nine consecutive Chinese patients (69 males, 20 females) with acute myocardial infarction treated by 100 mg recombinant tissue plasminogen activator (7 intracoronarily, 82 intravenously) at 3.7 +/- 1.0 h after onset, and intravenous heparin or dipyridamole therapy started at 3 h, were studied prospectively. Their mean age was 59.6 +/- 10.6 yr. Forty-six patients (51.7%) had anterior and 39 patients (43.8%) had inferior infarcts. Clinical evidence of reperfusion were seen in 63 patients (70.8%), while new complications included hypotension (5.6%), heart failure (6.7%), cardiac arrhythmias (76.4%) majority of which are related to reperfusion and self-remitting, haematoma around vascular access sites (23.6%), melaena (3.3%) and cerebral infarction (2.2%). Maximal changes in coagulation profiles were seen at 3 h, including a decrease in fibrinogen by 64.2% and an increase in fibrin degradation products by 47 times. The changes in haemostatic variables were not related to body weight or bleeding complications. Nine patients (10.1%) had recurrence of angina and 6 patients (6.9%) died due to pump failure and reinfarction. Angiogram at 14 days confirmed TIMI 2 or 3 patency of infarct-related arteries in 63 out of 73 (86.3%) patients, with a mean global ejection fraction of 52.5 +/- 12.4%. Nearly all survivors could maintain class I-II functional status after discharge. The safety and promise of recombinant tissue plasminogen activator for acute myocardial infarction in the Chinese were confirmed.