The Coagulopathy of Acute Leukemia

The influence of low molecular weight heparin on the intravascular activation of the coagulation system in patients with acute leukemia during induction chemotherapy--report of a prospective randomized study

Intravascular activation of the coagulation system can already be observed in the majority of patients with acute leukemia (AL) at the time of diagnosis. This activation can be further enhanced by chemotherapy. The study comprised of 46 patients with AL, randomly divided into two groups. Twenty-three patients received prophylactic doses of nadroparin (Fraxiparine). Thrombin-antithrombin complexes (TAT), prothrombin fragment (F1 + 2), D-dimer (DD), plasmin-antiplasmin complexes (PAP) and antithrombin III (AT III) activity were determined in all patients. The tests were performed before treatment, and on the 3rd and 8th days of chemotherapy. The TAT, F1 + 2, DD and PAP concentrations were found to be elevated in 83% of patients already at the time of diagnosis. No significant difference between either groups test results was noted when either tested before treatment or on the third day of therapy. DIC (disseminated intravascular coagulation) syndrome appeared in two patients receiving heparin prophylaxis and in three patients to whom this treatment was not administered. The concentrations of activation markers on the eighth day of chemotherapy were lower than at the beginning of treatment in most of the patients receiving nadroparin. At this time there were no laboratory signs of DIC in any of the patients receiving heparin prophylaxis.

IN CONCLUSION

although the application of prophylactic doses of nadroparin does not prevent DIC syndrome during first days of chemotherapy, it may limit the intravascular activation of the coagulation system during later chemotherapy.

Assessment of coagulation disorders in patients with acute leukemia before and after cytostatic treatment

Coagulation disorders are often the reason for fatal bleeding in acute promyelocytic leukemia. Their occurrence as well as pathogenesis and prognostic significance in other subtypes of acute myelogenous leukemia and acute lymphoblastic leukemia is less known. Tests were carried out in 70 patients including 49 with AML and 21 with ALL. In all patients thrombin-antithrombin complexes (TAT), D-dimer (DD) and plasmin-antiplasmin complexes (PAP), antithrombin III activity, fibrinogen/fibrin degradation products, APTT and PT were determined. The tests were performed on diagnosis and after cytostatic treatment. The level of TAT, DD and PAP was elevated in 83% of the patients on diagnosis and in 90% after treatment. The highest values were observed in AML M3 patients. Among leukemic patients with normal levels of TAT, DD and PAP at diagnosis, cytostatic treatment had a negligible effect on the level of these markers. During remission the levels of these markers returned to the normal values while in patients without remission they were either elevated or returned to normal values. No correlation between the levels of activation markers and remission rate was reported. DIC was diagnosed in 13 patients including three after chemotherapy. The DIC was acute or subacute in AML and chronic in ALL patients. In the majority of acute leukemia patients there were already changes on diagnosis indicating coagulation activation. Except for AML M3, these usually had a subclinical course. The TAT, DD and PAP tests are not reliable markers of remission in acute leukemias.