Background: The concentrations of plasma hemostatic proteins were analyzed prospectively in 42 children with acute lymphoblastic leukemia (ALL), treated according to the protocol ALL-BFM-90.
Procedure: Treatment included glucocorticosteroids (GC), E. coli L-asparaginase (Asparaginase, Medac) or Erwinia L-asparaginase (Erwinase, Speywood), vincristine, anthracyclines and intrathecal methotrexate. The analysis of hemostatic proteins was performed during induction and re-induction therapy.
Results: At diagnosis, the plasma concentrations of fibrinogen, antithrombin III (AT), plasminogen and protein C were within normal limits, whereas the von Willebrand factor antigen (vWF:Ag) was elevated. After eight days of mono-therapy with GC the concentration of fibrinogen decreased to 59%, vWF:Ag decreased to 67%, AT increased to 124%, protein C increased to 201% of the initial value (mean all p < or = 0.01), while the concentration of plasminogen remained unchanged. During the re-induction phase, the concentrations of the hemostatic proteins, with exception of vWF:Ag, altered in a similar way in response to GC as observed during the induction phase. Administration of two doses of E. coli L-asparaginase (10,000 U/m2) during the induction therapy led to a significant decrease of AT (123 +/- 24 to 63 +/- 15%/mL), protein C (168 +/- 34 to 87 +/- 19%/mL), plasminogen (94 +/- 21 to 41 +/- 12%/mL) and fibrinogen (148 +/- 59 to 79 +/- 30 mg/dL, p < or = 0.01 for all parameters). In contrast, administration of two doses of Erwinia L-asparaginase (10,000 U/m2) during re-induction therapy did not lead to change in the concentration of AT, protein C or plasminogen, and the decrease in fibrinogen (162 +/- 17 to 121 +/- 24 mg/dL) was less pronounced.
Conclusions: Our results indicate that GC and E. coli L-asparaginase, in particular, induce hemostatic alterations which have implications on our understanding of thrombotic and hemorrhagic events during the treatment of ALL in children.