Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.4.21.5 (thrombin)
 33,306 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Serial coagulation studies were performed in 26 pediatric patients with acute lymphoblastic leukemia during initial induction therapy with vincristine, prednisone, and L-asparaginase. Prolongation of screening coagulation tests was frequent: prothrombin time (in 16 of 26 patients), partial thromboplastin time (23/26) and thrombin time (21/26). In all 26 patients fibrinogen levels fell below .20 g/100 ml and 16 had levels below .10 g/100 ml. Sixteen patients had plasma coagulation factor assays performed. In these 16 patients, Factor XI was less than 40% in 14 and Factor XI was less than 70% in 9, with only a few scattered low levels of other factors. There were no clinical bleeding episodes. Coagulation abnormalities returned to normal at the completion of L-asparaginase therapy while the patients remained on vincristine and prednisone.
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PMID:The effect of L-asparaginase of plasma coagulation factors in acute lymphoblastic leukemia. 26 3

To evaluate the occurrence of hypercoagulability during treatment with L-asparaginase (L-ase), thrombin-antithrombin complex (TAT) and D-dimer levels in plasma were serially measured in 15 consecutive adult patients with acute lymphoblastic leukaemia or lymphoblastic lymphoma who had recently completed a chemotherapy cycle with cytosine arabinoside and methotrexate. The first eight patients (group A) received i.v. L-ase alone (20,000 U/m2 on alternate days over 10 d); the last seven patients (group B) received, in addition to L-ase, bolus injection of antithrombin concentrate (2000 U) on alternate days for a total of six administrations, beginning with the second L-ase infusion. Increased levels of TAT (P less than 0.05) and D-dimer (P less than 0.01) were observed prior to L-ase, possibly related to inflammation and cytolysis secondary to previous chemotherapy. In patients treated with L-ase alone, further elevation of TAT (P less than 0.05) and persistence of increased D-dimer were observed, associated with marked reduction of the anticoagulant activities of protein C, protein S and antithrombin III. At variance, in patients receiving antithrombin III supplementation there was no increase of TAT and a normalization of D-dimer levels occurred during L-ase treatment. In these patients, mean plasma antithrombin III activity was maintained at levels higher than 70% of normal throughout the treatment. The rate of decline of fibrinogen, factor IX, protein C and protein S was unaffected by antithrombin III supplementation, indicating that hypercoagulability has little if any relevance for the reduction of coagulation factors and inhibitors induced by L-ase treatment. The usefulness of antithrombin III concentrates in preventing thromboembolic complications in patients submitted to L-ase treatment remains to be determined.
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PMID:Hypercoagulability during L-asparaginase treatment: the effect of antithrombin III supplementation in vivo. 218 89

We describe 2 adult patients with acute lymphoblastic leukaemia (ALL) who died from pulmonary embolism following L-asparaginase treatment. Since this drug is known to cause a decrease in antithrombin III, the most important protein physiologically involved in the neutralization of thrombin, we studied the behaviour of this inhibitor in 14 ALL patients treated with a protocol including a 14-day course of L-asparaginase. A significant but transient fall of biological and immunological antithrombin III and a concomitant reduction of fibrinogen were documented.
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PMID:Fatal pulmonary embolism and antithrombin III deficiency in adult lymphoblastic leukaemia during L-asparaginase therapy. 640 3

L-asparaginase, a chemotherapeutic agent employed in the treatment of acute lymphocytic leukemia (ALL), is known to depress the synthesis of numerous plasma proteins. The plasma concentration of the major protease inhibitor of the coagulation mechanism, antithrombin III, is substantially decreased in patients receiving this drug. This observation has generated speculation that L-asparaginase may induce a hypercoagulable state in humans. To examine this hypothesis, we studied ten patients with ALL in remission who were being treated with the above chemotherapeutic agent. Our data revealed that infusion of this enzyme leads to a marked decrease in the plasma concentrations of prothrombin as well as antithrombin III. However, we have also observed a constant level of thrombin generation during the same period of time as monitored by plasma levels of prothrombin activation fragment (F1 + 2) and thrombin-antithrombin complex (TAT). Based upon these findings we suggest that administration of L-asparaginase does not usually lead to the induction of a hypercoagulable state.
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PMID:L-asparaginase induced antithrombin III deficiency: evidence against the production of a hypercoagulable state. 685 92

Platelet aggregation studies were performed on 10 pediatric patients with acute lymphoblastic leukemia (ALL) receiving induction therapy with vincristine, prednisone, and L-asparaginase. An isolated abnormality in platelet aggregation in response to collagen was found in all patients during the course of therapy. Platelet aggregation in response to collagen normalized following the discontinuation of L-asparaginase, while patients were still on vincristine and prednisone. In contrast to the abnormal collagen response, platelet aggregation induced by epinephrine, arachidonic acid, adenosine diphosphate (ADP), and thrombin were normal both during and following therapy. In the one patient with a normal platelet count before therapy, aggregation induced by all agents was normal. This selective abnormality in collagen aggregation therefore appears to result from therapy, with the use of L-asparaginase in particular being implicated.
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PMID:Selective deficiency in collagen-induced platelet aggregation during L-asparaginase therapy. 693 65

In 2 children treated for acute lymphoblastic leukemia (ALL), sural phlebitis followed treatment with L-asparaginase. The latter was responsible for a decreased synthesis of antithrombin III (AT III) resulting in low plasma activity. Treatment with heparin was not successful and only fresh plasma led to recovery. The activity of AT III, a progressive inhibitor of thrombin and cofactor of heparin, is always below 50% after L-asparaginase. However, since the risk of thrombosis is very low, interruption of treatment and fresh frozen plasma are needed only when additional risk factors are present.
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PMID:[L-asparaginase, antithrombin III deficiency and thromboses (author's transl)]. 694 99

Hemostatic function was studied sequentially in 12 children receiving L-asparaginase, vincristine, and prednisone as remission induction chemotherapy for acute lymphoblastic leukemia. The three-week period of L-asparaginase therapy was characterized by progressive decreases in plasma antithrombin, plasminogen, and fibrinogen concentrations, and by progressive increases in plasma clotting times (prothrombin time, partial thromboplastin time, thrombin time). Platelet counts rose rapidly during the third and fourth weeks of therapy as bone marrow remission was achieved. Factor V levels increased steadily during a five-week period, perhaps related to vincristine or prednisone therapy. Recent reports of thrombosis and hemorrhage in children and adults receiving L-asparaginase may be explained by this complex set of abnormalities in coagulation and coagulation control.
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PMID:The effect of L-asparaginase on antithrombin, plasminogen, and plasma coagulation during therapy for acute lymphoblastic leukemia. 695 22

Thrombotic events have been reported in acute lymphoblastic leukaemia patients, especially during or after L-asparaginase administration. A so-called L-asparaginase associated coagulopathy has been well recognized, being characterized by a hypercoagulable state (decrease of antithrombin III, plasminogen, protein C, protein S and increase of prothrombin fragment F1 + 2, thrombin-antithrombin complexes and fibrinopeptide A). The aim of this study was to determine whether the supplementation of antithrombin III (AT-III) concentrates could improve the L-asparaginase associated coagulopathy, thereby blocking the activation of the haemostatic system. In 25 adult patients with acute lymphoblastic leukaemia (M 19, F6, mean age 34 years) antithrombin III (AT-III) concentrates were administered at daily doses of 50 U/kg for 10 consecutive days from the beginning of L-asparaginase therapy (6,000 U/m2/day s.c. for 7 days), given according to the GIMEMA ALL 0288 trial. A marked increase of antithrombin III was recorded on days IV-VIII-XI (P < 0.001). No changes in protein C, protein S, plasminogen, alpha 2-antiplasmin, factor VII and platelet count were observed and there was no increase in markers of hypercoagulability. There was no evidence of disseminated intravascular coagulation. In conclusion, AT-III concentrate supplementation during L-asparaginase therapy, by the achievement of high levels of antithrombin III, is associated with a lack of activation of the haemostatic system and appears to overcome the complex coagulopathy associated with L-asparaginase.
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PMID:Antithrombin III infusion suppresses the hypercoagulable state in adult acute lymphoblastic leukaemia patients treated with a low dose of Escherichia coli L-asparaginase. A GIMEMA study. 751 43

It is well known that L-asparaginase (L-Ase) treatment may cause thrombotic events in patients with acute lymphoblastic leukemia (ALL). The mechanism of this effect is not well understood although a reduction in plasma antithrombin III (AT III) levels is observed. In our study, a group of patients treated with L-Ase received AT III concentrates as adjuvant treatment. This adjuvant treatment reduced the levels of plasma D-dimer and thrombin-antithrombin complex, which are considered as early markers of a hypercoagulability state. These preliminary data suggest that large randomized trials will have to be conducted to improve our understanding of the role of AT III concentrates in ALL therapy.
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PMID:L-asparaginase in acute lymphoblastic leukemia treatment: the role of human antithrombin III concentrates in regulating the prothrombotic state induced by therapy. 772 51

Three out of 21 patients treated at the Children's Hospital of Eastern Switzerland for ALL or NHL with the respective BFM-90 protocols experienced thrombotic complications during Erwinia L-asparaginase therapy. We therefore investigated the development of the haemostatic imbalance in six children during the induction phase of both protocols. In the average, elevated thrombin generation was found simultaneously to an increase in fibrinogen, cross-linked fibrin degradation products and platelet counts between protocol days 28 to 35. This period thus seems to harbour an increased potential of hypercoagulability which could explain the accumulation of thrombotic complications described by Sutor et al. Moreover, day to day investigations just before and one day after L-asparaginase administration did not show any relevant change in the above named parameters, thus rather indicating a cumulative than a single dose effect of Erwinia L-asparaginase therapy on the coagulation system. These findings lead to the question if the prophylactic use of anticoagulants might reduce the hypercoagulability seen during L-asparaginase therapy, which is currently under investigation in our institutions.
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PMID:Increased thrombin generation during fibrinogen and platelet recovery as an explanation for hypercoagulability in children with L-asparaginase therapy for ALL or NHL: a preliminary report. 796 34


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