Thrombotic and hemorrhagic strokes complicating early therapy for childhood acute lymphoblastic leukemia

Sudden cerebrovascular insults occurred during or immediately following remission induction therapy in 4 children with acute lymphoblastic leukemia. In 3, cerebral infarction was due to thrombosis. In the fourth, an intracerebral hematoma developed representing either frank hemorrhaging or a hemorrhagic infarction. None of the patients had central nervous system leukemia or extreme leukocytosis at the time of diagnosis. Symptoms were obtundation, hemiparesis, seizures, and headache. The induction chemotherapy included L‐asparaginase which causes deficiencies of antithrombin, plasminogen, fibrinogen, and factors IX and XI. These hemostatic abnormalities may explain the thromboses and bleeding observed in these children.