Intravascular coagulation phenomena associated with prevalent fall in fibrinogen and plasminogen during L-asparaginase treatment in leukemic children.

12 children affected by acute lymphoblastic leukemia had higher baseline levels of Normotest, Antithrombin III activity (AT III:A) and antigen (AT III:Ag) than those found in the control group, due to increased liver protein synthesis, as shown by the higher values of 305llbumin. Treatment with L-asparaginase (L-Asp) induced a marked decrease in fibrinogen and plasminogen and only a slight but significant reduction in AT III:A, AT III:Ag, protein C and alpha 2 antiplasmin levels. Platelet counts progressively increased. Each single L-Asp administration acutely induced (as recorded in the 2-hour postadministration samples) a significant increase in fibrinopeptide A values and reduction in several factors and inhibitors, due to activation of coagulation and consumption phenomena. It is suggested that these acute changes, but not the marked and selective reduction in fibrinogen and plasminogen, were partly compensated during L-Asp treatment by an overall increase in clotting and nonclotting protein synthesis in the liver.